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000
FXUS62 KRAH 181904
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
255 PM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...

MON/MON NIGHT: WILL HOLD ONTO JUST A FEW HOURS OF SHOWERS IN THE FAR
NE EARLY MON MORNING... CONSIDERING THAT THE MODELS HAVE BEEN
TRENDING A BIT FASTER TO MOVE PRECIP OUT OF CENTRAL NC... AND WILL
FOLLOW WITH A PERIOD OF NO POPS FOR MID TO LATE MORNING... UNTIL THE
ONSET OF CONVECTION. STILL LOOKS LIKE A GOOD PROBABILITY OF STRONG
TO SEVERE STORMS MON AFTERNOON INTO EARLY EVENING WITH A FEW
SUPERCELLS POSSIBLE. WE`LL BE FULLY IN THE WARM SECTOR WITH WARM
MOIST AIR NEAR THE GROUND AND A GOOD PUNCH OF MID LEVEL DRY AIR
COMING IN FROM THE SW. LATEST MODEL RUNS ARE SHOWING A LITTLE BETTER
INSTABILITY THAN YESTERDAY`S RUNS FOR MON AFTERNOON... WITH MUCAPE
OF 1000-2000 J/KG ON THE GFS AND 1500-3000 J/KG ON THE NAM... AND
SREF MEAN MLCAPE VALUES PEAKING AT 1200-1500 J/KG... ALTHOUGH THE
DEEP LAYER SHEAR STILL LOOKS MARGINAL AT AROUND 30 KTS. NAM/GFS BUFR
SOUNDINGS SHOW A WEAK CAP LOCATED BETWEEN 1 AND 2 KM AGL IN THE
MORNING... BREAKING EARLY IN THE AFTERNOON... AND ONCE IT DOES...
CONVECTION SHOULD DEVELOP AND BECOME VIGOROUS QUICKLY WITH BROAD AND
DEEP CAPE IN THE MID-UPPER LEVELS. DYNAMIC FORCING FOR ASCENT WILL
BE PRESENT AS WELL WITH STRONG UPPER DIVERGENCE IN THE LEFT EXIT
REGION OF A 140 KT SUBTROPICAL JET... AND A SHOT OF MID LEVEL DPVA
AS THE TROUGH AXIS ROTATES UP THROUGH THE AREA. WILL MAINTAIN A
MENTION IN THE HAZARDOUS WEATHER OUTLOOK OF DAMAGING WIND AS THE
PRIMARY THREAT GIVEN THE ABUNDANCE OF DRY AIR 700-300 MB... HOWEVER
THE EXPECTED CAPE IN THE -10C TO -30C LAYER APPEARS SUFFICIENT TO
SUPPORT LARGE HAIL IF WE CAN GET ENOUGH MOISTURE ALOFT. THICKNESSES
ARE PROJECTED TO START THE DAY AROUND 20 M ABOVE NORMAL... SO HIGHS
IN THE UPPER 70S TO MID 80S (NW TO SE) LOOK ATTAINABLE WITHIN GOOD
WARM AIR ADVECTION. WILL TREND OUT SHOWERS/STORMS IN THE MID-LATE
EVENING FROM WEST TO EAST... WITH COLD FRONTAL PASSAGE EXPECTED LATE
OVERNIGHT. LOWS FROM THE LOWER 50S NW TO AROUND 60 SE.

TUE-SAT: THE COLD FRONT WILL HAVE PUSHED OFF THE COAST BY DAYBREAK
TUE... AS MILD HIGH PRESSURE BUILDS IN FROM THE WEST. A LARGE VORTEX
IS EXPECTED TO SIT AND SPIN OVER THE NRN GREAT LAKES THROUGH
MIDWEEK... BEFORE WOBBLING EASTWARD TO NEW ENGLAND BY LATE SAT...
ALL THE WHILE ENCOMPASSING A LARGE CHUNK OF CENTRAL AND EASTERN NOAM
INCLUDING THE MIDATLANTIC REGION. AS THE MODIFIED SURFACE HIGH
BUILDS IN... EXPECT TEMPS TO BE A BIT BELOW NORMAL TUE/WED... BUT
READINGS WILL REBOUND ONCE THE SURFACE HIGH DRIFTS TO OUR SOUTHEAST
AND OFFSHORE LATE WED... SO EXPECT TEMPS BACK UP NEAR NORMAL THU.
ONE PARTICULARLY POTENT WAVE ROTATING THROUGH THE BROAD BASE OF THE
LOW LATE IN THE WEEK IS LINKED TO A SURFACE COLD FRONT WHICH IS
EXPECTED TO PUSH SOUTHEAST THROUGH NC LATE THU OR THU EVENING.
IMPROVING MOISTURE STREAMING INTO NC AHEAD OF THIS FRONT SHOULD
YIELD A FEW SHOWERS MAINLY WED NIGHT AND THU... HOWEVER THE LOW
LEVEL FLOW WILL REMAIN LIGHT WITH MINISCULE TAPPING OF ATLANTIC OR
GULF MOISTURE... AND LITTLE IN THE WAY OF FORCING FOR ASCENT GIVEN
THE FAST WNW GENTLY CYCLONIC FLOW ALOFT... SO EXPECT POPS TO HOLD
UNDER CLIMATOLOGY. FRONTAL PASSAGE LATE THU WILL INTRODUCE A COOLER
AIR MASS IN THE FORM OF A SPRAWLING CANADIAN HIGH EXPANDING SSE FROM
CENTRAL CANADA FOR FRI/SAT... SO WILL TREND BACK TO DRY WEATHER WITH
BELOW NORMAL TEMPS. -GIH

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 145 PM SATURDAY...

WHILE MOST LOCATIONS ACROSS CENTRAL NC WILL HAVE VFR CONDITIONS
THROUGH THIS EVENING...THERE WILL BE LOCALIZED AREAS OF MVFR
CEILINGS AND VISIBILITIES IN THE VICINITY OF SHOWERS. THESE ADVERSE
CONDITIONS WILL BE MOST LIKELY TO OCCUR NEAR KFAY THROUGH 22Z.

MOSTLY VFR CONDITIONS WILL GRADUALLY BECOME MVFR IN AREAS AFTER 05Z
AS AREAS OF FOG DEVELOP WITH SPOTS OF IFR/LIFR CEILINGS POSSIBLE.

AVIATION CONDITIONS WILL DETERIORATE SUNDAY MORNING AS AN
APPROACHING LOW PRESSURE SYSTEM WILL CAUSE RAIN SHOWERS TO
OVERSPREAD CENTRAL NC FROM THE SW. EXPECT MVFR CEILINGS WITH THIS
SHIELD OF SHOWERS. NEAR SFC WINDS WILL BE ELY...SUSTAINED 10-15KTS
WITH GUSTS 20-25KTS.

THE RAIN WILL DIMINISH FROM THE SW AFTER 00Z MONDAY WITH SHOWERS
VERY SPOTTY AFTER 06Z. RESIDUAL MOISTURE WILL LIKELY CAUSE
WIDESPREAD IFR/MVFR CEILINGS UNTIL EARLY MONDAY MORNING.

A STRONG LOW PRESSURE SYSTEM WILL TRAVERSE CLOSE TO CENTRAL NC
MONDAY. THIS SYSTEM INTERACTING WITH AVAILABLE MOISTURE AND
INSTABILITY WILL BRING A GOOD CHANCE FOR SCATTERED STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON-MONDAY EVENING.

IMPROVING AVIATION CONDITIONS WITH WIDESPREAD VFR CONDITIONS
ANTICIPATED FOR TUESDAY THROUGH THURSDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 181744
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
145 PM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 145 PM SATURDAY...

WHILE MOST LOCATIONS ACROSS CENTRAL NC WILL HAVE VFR CONDITIONS
THROUGH THIS EVENING...THERE WILL BE LOCALIZED AREAS OF MVFR
CEILINGS AND VISIBILITIES IN THE VICINITY OF SHOWERS. THESE ADVERSE
CONDITIONS WILL BE MOST LIKELY TO OCCUR NEAR KFAY THROUGH 22Z.

MOSTLY VFR CONDITIONS WILL GRADUALLY BECOME MVFR IN AREAS AFTER 05Z
AS AREAS OF FOG DEVELOP WITH SPOTS OF IFR/LIFR CEILINGS POSSIBLE.

AVIATION CONDITIONS WILL DETERIORATE SUNDAY MORNING AS AN
APPROACHING LOW PRESSURE SYSTEM WILL CAUSE RAIN SHOWERS TO
OVERSPREAD CENTRAL NC FROM THE SW. EXPECT MVFR CEILINGS WITH THIS
SHIELD OF SHOWERS. NEAR SFC WINDS WILL BE ELY...SUSTAINED 10-15KTS
WITH GUSTS 20-25KTS.

THE RAIN WILL DIMINISH FROM THE SW AFTER 00Z MONDAY WITH SHOWERS
VERY SPOTTY AFTER 06Z. RESIDUAL MOISTURE WILL LIKELY CAUSE
WIDESPREAD IFR/MVFR CEILINGS UNTIL EARLY MONDAY MORNING.

A STRONG LOW PRESSURE SYSTEM WILL TRAVERSE CLOSE TO CENTRAL NC
MONDAY. THIS SYSTEM INTERACTING WITH AVAILABLE MOISTURE AND
INSTABILITY WILL BRING A GOOD CHANCE FOR SCATTERED STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON-MONDAY EVENING.

IMPROVING AVIATION CONDITIONS WITH WIDESPREAD VFR CONDITIONS
ANTICIPATED FOR TUESDAY THROUGH THURSDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...WSS




000
FXUS62 KRAH 181744
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
145 PM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 145 PM SATURDAY...

WHILE MOST LOCATIONS ACROSS CENTRAL NC WILL HAVE VFR CONDITIONS
THROUGH THIS EVENING...THERE WILL BE LOCALIZED AREAS OF MVFR
CEILINGS AND VISIBILITIES IN THE VICINITY OF SHOWERS. THESE ADVERSE
CONDITIONS WILL BE MOST LIKELY TO OCCUR NEAR KFAY THROUGH 22Z.

MOSTLY VFR CONDITIONS WILL GRADUALLY BECOME MVFR IN AREAS AFTER 05Z
AS AREAS OF FOG DEVELOP WITH SPOTS OF IFR/LIFR CEILINGS POSSIBLE.

AVIATION CONDITIONS WILL DETERIORATE SUNDAY MORNING AS AN
APPROACHING LOW PRESSURE SYSTEM WILL CAUSE RAIN SHOWERS TO
OVERSPREAD CENTRAL NC FROM THE SW. EXPECT MVFR CEILINGS WITH THIS
SHIELD OF SHOWERS. NEAR SFC WINDS WILL BE ELY...SUSTAINED 10-15KTS
WITH GUSTS 20-25KTS.

THE RAIN WILL DIMINISH FROM THE SW AFTER 00Z MONDAY WITH SHOWERS
VERY SPOTTY AFTER 06Z. RESIDUAL MOISTURE WILL LIKELY CAUSE
WIDESPREAD IFR/MVFR CEILINGS UNTIL EARLY MONDAY MORNING.

A STRONG LOW PRESSURE SYSTEM WILL TRAVERSE CLOSE TO CENTRAL NC
MONDAY. THIS SYSTEM INTERACTING WITH AVAILABLE MOISTURE AND
INSTABILITY WILL BRING A GOOD CHANCE FOR SCATTERED STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON-MONDAY EVENING.

IMPROVING AVIATION CONDITIONS WITH WIDESPREAD VFR CONDITIONS
ANTICIPATED FOR TUESDAY THROUGH THURSDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...WSS





000
FXUS62 KRAH 181450
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1050 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT





000
FXUS62 KRAH 181450
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1050 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT




000
FXUS62 KRAH 181450
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1050 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT





000
FXUS62 KRAH 181450
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1050 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM SATURDAY...

BULK OF LIGHT RAIN ASSOCIATED WITH A MINOR S/W CROSSING SC EARLIER
THIS MORNING HAS PRETTY MUCH DEPARTED OUR FAR SE COUNTIES AS THE S/W
HAS REACHED THE COAST. 12Z UPPER AIR ANALYSIS DEPICT A WEAK TROUGH
AXIS LINGERING ACROSS CENTRAL NC. THIS FEATURE WILL LIKELY PERSIST
INTO THE AFTERNOON-EARLY EVENING HOURS AS WINDS ARE FAIRLY LIGHT.
LOW LEVEL FLOW WILL BECOME ELY THIS AFTERNOON AND INCREASE WITH
TIME. THIS WILL RESULT IN WEAK CONVERGENCE ALONG LOW LEVEL TROUGH.
WITH AFTERNOON HEATING OF THE RELATIVELY MOIST AIR MASS IN
PLACE...WILL LIKELY SEE THE DEVELOPMENT OF ISOLATED SHOWERS (T-
STORM?) ALONG THIS BOUNDARY ACROSS CENTRAL NC AFTER 3 PM.

EXPECT A MIXTURE OF SUN AND CLOUDS THIS AFTERNOON WITH CLOUDY SPELLS
MORE PREVALENT THAN MOSTLY SUNNY CONDITIONS. MOST LOCATIONS SHOULD
BE WITHIN A DEGREE OR TWO OF 80 DEGREES FOR AFTERNOON HIGH TEMPS. IF
CLOUD COVER REMAINS MOSTLY CLOUDY THROUGH MID AFTERNOON...HIGH TEMPS
IN THE MID-UPPER 70S WILL BE MORE COMMON.

TONIGHT...ANY SHOWERS OCCURRING AT SUNSET WILL DIMINISH WITH LOSS OF
HEATING. SHOULD SEE INCREASING/THICKENING CLOUD COVER SPREADING OVER
HEAD FROM THE SW AS A POTENT LOW PRESSURE SYSTEM MOVES TOWARD OUR
REGION. WILL PROBABLY SEE A FEW SHOWERS SKIRT ACROSS THE SOUTHERN-
WESTERN PIEDMONT COUNTIES PRIOR TO DAYBREAK WITH BEST CHANCE OF
MEASURABLE RAIN OCCURRING SOUTH OF A LEXINGTON-LAURINBURG LINE. MIN
TEMPS 60-64 WITH A FEW UPPER 50S PROBABLE ACROSS THE FAR NORTHEAST
WHERE CLOUD COVER WILL BE INITIALLY THINNER.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT




000
FXUS62 KRAH 180940
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
540 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 400 AM SATURDAY...

CONFIDENCE: BELOW AVERAGE CONFIDENCE IN FORECAST DETAILS DUE TO A
SPLIT FLOW SYNOPTIC REGIME AND ENHANCED UNCERTAINTY WITH REGARD TO
THE EVOLUTION OF UPSTREAM CONVECTION OVER THE NEXT 24 HRS.

OVERVIEW: A DEEP UPPER LEVEL LOW CENTERED OVER COLORADO AT 06Z WILL
TRACK SLOWLY EAST INTO THE CENTRAL/SOUTHERN PLAINS BY 12Z SUN...
SLIGHTLY IN ADVANCE OF NORTHERN STREAM SHORTWAVE ENERGY DIGGING
SOUTHEAST ACROSS WESTERN CANADA INTO THE UPPER MIDWEST. IN THE LOWER
LEVELS...THE ILL-DEFINED MSLP/HEIGHT PATTERN IN PLACE TODAY WILL
GIVE WAY TO A STRONGER GRADIENT /BETTER DEFINED PATTERN/ LATER
TONIGHT AS A WEAK SFC LOW DEVELOPS UPSTREAM ACROSS THE LOWER/CENTRAL
MS RIVER VALLEY AND HIGH PRESSURE EXTENDS SOUTHWARD THROUGH EASTERN
CANADA INTO THE MID-ATLANTIC IN ASSOC/W SUBSIDENCE IN THE WAKE OF
SHORTWAVE ENERGY MOVING OFFSHORE THE NEW ENGLAND COAST IN SPEEDY NW
FLOW ALOFT.

PRECIPITATION: DPVA ATTENDANT A DEAMPLIFYING SHORTWAVE PROGRESSING
EAST INTO A MOIST AND MARGINALLY UNSTABLE (MLCAPE ~100 J/KG) AIRMASS
IN PLACE ACROSS THE CAROLINAS HAS ALLOWED LIGHT SHOWER ACTIVITY TO
PERSIST OVER THE SW PIEDMONT AND SANDHILLS EARLY THIS MORNING.
EXPECT SHOWER ACTIVITY TO SHIFT EAST INTO THE SANDHILLS/SE COASTAL
PLAIN BY ~12Z IN CONCERT WITH THE AFOREMENTIONED WAVE. SUBSIDENCE
(ALBEIT WEAK) IN THE WAKE OF THE DEAMPLIFYING SHORTWAVE SHOULD ACT
TO SUPPRESS ACTIVITY THE REMAINDER OF THE MORNING. A SHORTWAVE RIDGE
WILL DEVELOP OVER THE REGION THIS AFTERNOON INTO TONIGHT...
DOWNSTREAM OF THE UPPER LOW PROGRESSING INTO THE CENTRAL PLAINS.
SHOWER ACTIVITY SHOULD RE-DEVELOP OVER SC AND EASTERN NC THIS
AFTERNOON IN THE PRESENCE OF ABUNDANT MOISTURE/MARGINAL DIURNAL
DESTABILIZATION AND WEAK DPVA ATTENDANT TRANSIENT SMALL AMPLITUDE
WAVES ALOFT...TRACKING WESTWARD INTO CENTRAL NC LATER THIS AFTERNOON
THROUGH THIS EVENING IN ASSOC/W THE DEVELOPMENT OF AN EASTERLY
/ONSHORE/ LOW-LEVEL FLOW. GIVEN WEAK FORCING...WEAK MID-LEVEL LAPSE
RATES AND ABUNDANT CLOUD COVER...EXPECT SCATTERED LOW-TOPPED SHOWERS
AT BEST...WITH ACTIVITY SHIFTING WESTWARD AND DECREASING IN COVERAGE
WITH NOCTURNAL STABILIZATION OVERNIGHT.

TEMPS: HIGHS TODAY WILL BE TEMPERED BY CLOUD COVER AND AN
INCREASINGLY ONSHORE /EASTERLY/ LOW-LEVEL FLOW...IN THE MID/UPPER
70S. LOWS TONIGHT IN THE 60S...PERHAPS UPPER 50S IN THE FAR NE
COASTAL PLAIN IN CLOSER VICINITY TO THE SFC RIDGE AXIS EXTENDING
INTO THE REGION FROM THE NORTH. -VINCENT

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

OVERVIEW: THE SHORTWAVE RIDGE IN PLACE TONIGHT WILL SHIFT OFFSHORE
THE CAROLINA/MID-ATLANTIC COAST ON SUNDAY AS A SOMEWHAT DEAMPLIFIED
UPPER LEVEL LOW TRACKS EASTWARD FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...PROPELLING A WEAK WARM FRONT /LOW-LEVEL
TROUGH/ NORTHEASTWARD FROM THE DEEP SOUTH INTO THE CAROLINAS.

PRECIPITATION: EXPECT AN EXCELLENT CHANCE FOR PRECIP ACROSS ALL OF
CENTRAL NC SUN/SUN NIGHT IN ASSOC/W DPVA ATTENDANT INCREASINGLY
NUMEROUS SMALL AMPLITUDE WAVES EMBEDDED WITHIN STRENGTHENING SW FLOW
ALOFT AND LOW-LEVEL CONVERGENCE ATTENDANT THE WEAK WARM FRONT /LOW-
LEVEL TROUGH/ PROGRESSING ACROSS CENTRAL NC IN THE PRESENCE OF A
VERY MOIST (PWAT ~1.75") ALBEIT MARGINALLY UNSTABLE AIRMASS. FORCING
MAY BE FURTHER AUGMENTED BY THE PRESENCE OF AN MCV AND/OR OUTFLOW
ATTENDANT ONGOING CONVECTION PROGRESSING INTO THE REGION FROM THE
SW...DEPENDING ON THE EVOLUTION OF UPSTREAM CONVECTION LATE TONIGHT
AND EARLY SUN. REGARDLESS...EXPECT PRECIP CHANCES INCREASING FROM SW-
NE SUN MORNING...WITH WIDESPREAD PRECIPITATION BY SUN AFTERNOON.
EXPECT THE HEAVIEST PRECIPITATION TO FALL ACROSS THE WESTERN
PIEDMONT...IN CLOSER VICINITY TO STRONGER DPVA AND ATTENDANT SFC
CYCLONE TRACKING NE THROUGH THE TN VALLEY AND IN CLOSER VICINITY TO
THE MOUNTAINS WHERE FORCING WILL BE LOCALLY AUGMENTED BY CONVERGENCE
/OROGRAPHIC ASCENT/ ATTENDANT A STRENGTHENING SOUTHEASTERLY LLJ
BETWEEN 15-21Z. PRECIP CHANCES SHOULD RAPIDLY DECREASE FROM SW-NE
ACROSS CENTRAL NC SUN EVE AS THE LOW-LEVEL TROUGH PROGRESSES
NORTHWARD ALONG THE MID-ATLANTIC COAST. RE-DEVELOPMENT OF ISOLD
SHOWER ACTIVITY CANNOT BE RULED OUT LATE SUN NIGHT GIVEN A CONTINUED
POTENTIAL FOR DPVA IN SW FLOW ALOFT...THOUGH POOR DIURNAL
TIMING...MID-LEVEL DRYING...AND THE LACK OF A LOW-LEVEL FOCUS
WILL ACT TO LIMIT AND/OR HINDER FURTHER DEVELOPMENT.

TEMPS: HIGHS SUN WILL BE LIMITED BY PRECIPITATION (WEST) AND
PERVASIVE CLOUD COVER FOLLOWED BY PRECIP (EAST)...IN THE 70S. LOWS
SUN NIGHT IN THE LOW/MID 60S GIVEN A SOUTHERLY BREEZE AND LITTLE IN
THE WAY OF AIRMASS CHANGE.

HAZARDS: CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO
ASCERTAIN DUE TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF
UPSTREAM CONVECTION IN THE DEEP SOUTH (AND ULTIMATE IMPACT ON
DOWNSTREAM ENV) TONIGHT /EARLY SUN/. FROM A PATTERN RECOGNITION
STANDPOINT...SEVERE WEATHER APPEARS UNLIKELY GIVEN THAT THE BEST
DPVA WILL REMAIN UPSTREAM ACROSS THE TN/OH VALLEY...DIURNAL TIMING
WILL BE POOR IN THE WESTERN PIEDMONT...AND DIURNAL DESTABILIZATION
WILL BE SIGNIFICANTLY HAMPERED ELSEWHERE/OTHERWISE BY MOIST-
ADIABATIC MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. GIVEN
DEEP MOISTURE (PWAT ~1.75")...ISOLD FLASH FLOODING WILL BE
POSSIBLE...PARTICULARLY IN URBAN AND FLOOD PRONE AREAS ACROSS THE
TRIAD/WESTERN PIEDMONT. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT




000
FXUS62 KRAH 180833
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
433 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 400 AM SATURDAY...

CONFIDENCE: BELOW AVERAGE CONFIDENCE IN FORECAST DETAILS DUE TO A
SPLIT FLOW SYNOPTIC REGIME AND ENHANCED UNCERTAINTY WITH REGARD TO
THE EVOLUTION OF UPSTREAM CONVECTION OVER THE NEXT 24 HRS.

OVERVIEW: A DEEP UPPER LEVEL LOW CENTERED OVER COLORADO AT 06Z WILL
TRACK SLOWLY EAST INTO THE CENTRAL/SOUTHERN PLAINS BY 12Z SUN...
SLIGHTLY IN ADVANCE OF NORTHERN STREAM SHORTWAVE ENERGY DIGGING
SOUTHEAST ACROSS WESTERN CANADA INTO THE UPPER MIDWEST. IN THE LOWER
LEVELS...THE ILL-DEFINED MSLP/HEIGHT PATTERN IN PLACE TODAY WILL
GIVE WAY TO A STRONGER GRADIENT /BETTER DEFINED PATTERN/ LATER
TONIGHT AS A WEAK SFC LOW DEVELOPS UPSTREAM ACROSS THE LOWER/CENTRAL
MS RIVER VALLEY AND HIGH PRESSURE EXTENDS SOUTHWARD THROUGH EASTERN
CANADA INTO THE MID-ATLANTIC IN ASSOC/W SUBSIDENCE IN THE WAKE OF
SHORTWAVE ENERGY MOVING OFFSHORE THE NEW ENGLAND COAST IN SPEEDY NW
FLOW ALOFT.

PRECIPITATION: DPVA ATTENDANT A DEAMPLIFYING SHORTWAVE PROGRESSING
EAST INTO A MOIST AND MARGINALLY UNSTABLE (MLCAPE ~100 J/KG) AIRMASS
IN PLACE ACROSS THE CAROLINAS HAS ALLOWED LIGHT SHOWER ACTIVITY TO
PERSIST OVER THE SW PIEDMONT AND SANDHILLS EARLY THIS MORNING.
EXPECT SHOWER ACTIVITY TO SHIFT EAST INTO THE SANDHILLS/SE COASTAL
PLAIN BY ~12Z IN CONCERT WITH THE AFOREMENTIONED WAVE. SUBSIDENCE
(ALBEIT WEAK) IN THE WAKE OF THE DEAMPLIFYING SHORTWAVE SHOULD ACT
TO SUPPRESS ACTIVITY THE REMAINDER OF THE MORNING. A SHORTWAVE RIDGE
WILL DEVELOP OVER THE REGION THIS AFTERNOON INTO TONIGHT...
DOWNSTREAM OF THE UPPER LOW PROGRESSING INTO THE CENTRAL PLAINS.
SHOWER ACTIVITY SHOULD RE-DEVELOP OVER SC AND EASTERN NC THIS
AFTERNOON IN THE PRESENCE OF ABUNDANT MOISTURE/MARGINAL DIURNAL
DESTABILIZATION AND WEAK DPVA ATTENDANT TRANSIENT SMALL AMPLITUDE
WAVES ALOFT...TRACKING WESTWARD INTO CENTRAL NC LATER THIS AFTERNOON
THROUGH THIS EVENING IN ASSOC/W THE DEVELOPMENT OF AN EASTERLY
/ONSHORE/ LOW-LEVEL FLOW. GIVEN WEAK FORCING...WEAK MID-LEVEL LAPSE
RATES AND ABUNDANT CLOUD COVER...EXPECT SCATTERED LOW-TOPPED SHOWERS
AT BEST...WITH ACTIVITY SHIFTING WESTWARD AND DECREASING IN COVERAGE
WITH NOCTURNAL STABILIZATION OVERNIGHT.

TEMPS: HIGHS TODAY WILL BE TEMPERED BY CLOUD COVER AND AN
INCREASINGLY ONSHORE /EASTERLY/ LOW-LEVEL FLOW...IN THE MID/UPPER
70S. LOWS TONIGHT IN THE 60S...PERHAPS UPPER 50S IN THE FAR NE
COASTAL PLAIN IN CLOSER VICINITY TO THE SFC RIDGE AXIS EXTENDING
INTO THE REGION FROM THE NORTH. -VINCENT

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

EXPECT AN EXCELLENT CHANCE FOR PRECIPITATION DURING THE DAY
SUNDAY...ESP FROM THE TRIANGLE WEST AND SOUTH...AS THE SOMEWHAT
DEAMPLIFIED UPPER LEVEL LOW TRACKS FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...THE SHORTWAVE RIDGE OVER THE REGION SHIFTS
OFFSHORE THE CAROLINA/MID-ATLANTIC COAST...AND A WEAK WARM FRONT
/LOW-LEVEL TROUGH/ TRACKS INTO THE REGION FROM THE SOUTHWEST.
CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO ASCERTAIN DUE
TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF UPSTREAM CONVECTION
(AND ULTIMATE IMPACT ON DOWNSTREAM ENV) ACROSS THE DEEP SOUTH
TONIGHT. FROM A PATTERN RECOGNITION STANDPOINT...DEEP CONVECTION AND
SEVERE WEATHER APPEAR UNLIKELY GIVEN THAT THE BEST DPVA WILL REMAIN
WELL UPSTREAM ACROSS THE OH VALLEY AND WESTERN TN VALLEY AND THAT
DIURNAL DESTABILIZATION WILL BE SIGNIFICANTLY HAMPERED BY
WEAK MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT




000
FXUS62 KRAH 180833
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
433 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TONIGHT...THEN SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT PROGRESSES
INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH THE
MOUNTAINS FROM THE WEST ON MONDAY...THEN TRACK EASTWARD THROUGH THE
CAROLINAS MONDAY NIGHT.

&&

.NEAR TERM /TODAY AND TONIGHT/...
AS OF 400 AM SATURDAY...

CONFIDENCE: BELOW AVERAGE CONFIDENCE IN FORECAST DETAILS DUE TO A
SPLIT FLOW SYNOPTIC REGIME AND ENHANCED UNCERTAINTY WITH REGARD TO
THE EVOLUTION OF UPSTREAM CONVECTION OVER THE NEXT 24 HRS.

OVERVIEW: A DEEP UPPER LEVEL LOW CENTERED OVER COLORADO AT 06Z WILL
TRACK SLOWLY EAST INTO THE CENTRAL/SOUTHERN PLAINS BY 12Z SUN...
SLIGHTLY IN ADVANCE OF NORTHERN STREAM SHORTWAVE ENERGY DIGGING
SOUTHEAST ACROSS WESTERN CANADA INTO THE UPPER MIDWEST. IN THE LOWER
LEVELS...THE ILL-DEFINED MSLP/HEIGHT PATTERN IN PLACE TODAY WILL
GIVE WAY TO A STRONGER GRADIENT /BETTER DEFINED PATTERN/ LATER
TONIGHT AS A WEAK SFC LOW DEVELOPS UPSTREAM ACROSS THE LOWER/CENTRAL
MS RIVER VALLEY AND HIGH PRESSURE EXTENDS SOUTHWARD THROUGH EASTERN
CANADA INTO THE MID-ATLANTIC IN ASSOC/W SUBSIDENCE IN THE WAKE OF
SHORTWAVE ENERGY MOVING OFFSHORE THE NEW ENGLAND COAST IN SPEEDY NW
FLOW ALOFT.

PRECIPITATION: DPVA ATTENDANT A DEAMPLIFYING SHORTWAVE PROGRESSING
EAST INTO A MOIST AND MARGINALLY UNSTABLE (MLCAPE ~100 J/KG) AIRMASS
IN PLACE ACROSS THE CAROLINAS HAS ALLOWED LIGHT SHOWER ACTIVITY TO
PERSIST OVER THE SW PIEDMONT AND SANDHILLS EARLY THIS MORNING.
EXPECT SHOWER ACTIVITY TO SHIFT EAST INTO THE SANDHILLS/SE COASTAL
PLAIN BY ~12Z IN CONCERT WITH THE AFOREMENTIONED WAVE. SUBSIDENCE
(ALBEIT WEAK) IN THE WAKE OF THE DEAMPLIFYING SHORTWAVE SHOULD ACT
TO SUPPRESS ACTIVITY THE REMAINDER OF THE MORNING. A SHORTWAVE RIDGE
WILL DEVELOP OVER THE REGION THIS AFTERNOON INTO TONIGHT...
DOWNSTREAM OF THE UPPER LOW PROGRESSING INTO THE CENTRAL PLAINS.
SHOWER ACTIVITY SHOULD RE-DEVELOP OVER SC AND EASTERN NC THIS
AFTERNOON IN THE PRESENCE OF ABUNDANT MOISTURE/MARGINAL DIURNAL
DESTABILIZATION AND WEAK DPVA ATTENDANT TRANSIENT SMALL AMPLITUDE
WAVES ALOFT...TRACKING WESTWARD INTO CENTRAL NC LATER THIS AFTERNOON
THROUGH THIS EVENING IN ASSOC/W THE DEVELOPMENT OF AN EASTERLY
/ONSHORE/ LOW-LEVEL FLOW. GIVEN WEAK FORCING...WEAK MID-LEVEL LAPSE
RATES AND ABUNDANT CLOUD COVER...EXPECT SCATTERED LOW-TOPPED SHOWERS
AT BEST...WITH ACTIVITY SHIFTING WESTWARD AND DECREASING IN COVERAGE
WITH NOCTURNAL STABILIZATION OVERNIGHT.

TEMPS: HIGHS TODAY WILL BE TEMPERED BY CLOUD COVER AND AN
INCREASINGLY ONSHORE /EASTERLY/ LOW-LEVEL FLOW...IN THE MID/UPPER
70S. LOWS TONIGHT IN THE 60S...PERHAPS UPPER 50S IN THE FAR NE
COASTAL PLAIN IN CLOSER VICINITY TO THE SFC RIDGE AXIS EXTENDING
INTO THE REGION FROM THE NORTH. -VINCENT

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 400 AM SATURDAY...

EXPECT AN EXCELLENT CHANCE FOR PRECIPITATION DURING THE DAY
SUNDAY...ESP FROM THE TRIANGLE WEST AND SOUTH...AS THE SOMEWHAT
DEAMPLIFIED UPPER LEVEL LOW TRACKS FROM THE CENTRAL PLAINS INTO THE
CENTRAL MS RIVER VALLEY...THE SHORTWAVE RIDGE OVER THE REGION SHIFTS
OFFSHORE THE CAROLINA/MID-ATLANTIC COAST...AND A WEAK WARM FRONT
/LOW-LEVEL TROUGH/ TRACKS INTO THE REGION FROM THE SOUTHWEST.
CONVECTIVE DETAILS FOR CENTRAL NC REMAIN DIFFICULT TO ASCERTAIN DUE
TO BELOW NORMAL CONFIDENCE IN THE EVOLUTION OF UPSTREAM CONVECTION
(AND ULTIMATE IMPACT ON DOWNSTREAM ENV) ACROSS THE DEEP SOUTH
TONIGHT. FROM A PATTERN RECOGNITION STANDPOINT...DEEP CONVECTION AND
SEVERE WEATHER APPEAR UNLIKELY GIVEN THAT THE BEST DPVA WILL REMAIN
WELL UPSTREAM ACROSS THE OH VALLEY AND WESTERN TN VALLEY AND THAT
DIURNAL DESTABILIZATION WILL BE SIGNIFICANTLY HAMPERED BY
WEAK MID-LEVEL LAPSE RATES AND PERVASIVE CLOUD COVER. -VINCENT

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...BADGETT





000
FXUS62 KRAH 180645
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...BADGETT
AVIATION...BADGETT





000
FXUS62 KRAH 180645
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 245 AM SATURDAY...

THE DEEP MOISTURE FLUX IS EXPECTED TO BE PUSHING EAST OF OUR REGION
BY 12Z/MONDAY. THE TIMING OF THE BACK EDGE OF THE MAIN SHIELD OF
WIDESPREAD RAIN IS STILL DIFFICULT TO PIN DOWN. USING THE ENSEMBLE
APPROACH... IT APPEARS THAT THE SIGNIFICANT WEATHER SHOULD BEGIN TO
CLEAR OUT BETWEEN 09Z-15Z OR SO FROM WEST TO EAST MONDAY MORNING.

ONCE THE MID LEVELS DRY OUT MONDAY... THE SW FLOW IN THE WARM SECTOR
SHOULD ALLOW FOR AT LEAST PARTIAL CLEARING DURING MONDAY AFTERNOON.
THIS WOULD SET US UP FOR SCATTERED CONVECTIVE DEVELOPMENT
PARTICULARLY ALONG THE PRE-FRONTAL TROUGH AND/OR COLD FRONT EXPECTED
TO ARRIVE LATE IN THE DAY AND DURING THE EVENING. THE LATEST
STATICAL MOS SUGGESTS HIGHS OF 75-80 IN THE NW RANGING TO POSSIBLY
85 IN THE SANDHILLS. THIS COMBINED WITH FORECAST DEW POINTS IN THE
MID 50S NW TO LOWER 60S COASTAL PLAIN WOULD YIELD MUCAPE VALUES OF
1500+ J/KG WITH 2000 J/KG POSSIBLE IN THE COASTAL PLAIN AND EASTERN
PIEDMONT. THE WINDS FROM THE SURFACE TO ALOFT WILL BECOME
UNIDIRECTIONAL FROM THE SW SUGGESTING THAT THE MAIN SEVERE WEATHER
MODE WOULD MOST LIKELY BE THE THREAT OF STRAIGHT LINE WIND GUSTS.
AFTER THE LULL IN THE POP MONDAY MORNING... WE WILL RAISE POP MONDAY
AFTERNOON AND EVENING INTO THE 40-50 PERCENT RANGE AND CONTINUE TO
HIGHLIGHT THE POTENTIAL FOR A COUPLE OF STRONG TO SEVERE
THUNDERSTORMS MONDAY AFTERNOON INTO THE EVENING.

FOR MONDAY NIGHT THROUGH FRIDAY... THE PATTERN WILL CHANGE BACK TO
ONE THAT IS MUCH DRIER AND COOLER WITH A PREDOMINATE NW FLOW ALOFT
OVER NC. A DRY COLD FRONT IS FAVORED TO PUSH SOUTH THROUGH NC ON
THURSDAY AFTERNOON OR NIGHT. THE TEMPERATURES SHOULD BE WARMEST
WEDNESDAY AND THURSDAY OUT AHEAD OF THE FRONT (70S)... AND COOL BACK
INTO THE 65-70 RANGE BY FRIDAY. LOWS SHOULD BE IN THE MID 40S TO MID
50S MUCH OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...BADGETT
AVIATION...BADGETT




000
FXUS62 KRAH 180532
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
123 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...BADGETT





000
FXUS62 KRAH 180532
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
123 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...BADGETT




000
FXUS62 KRAH 180532
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
123 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...BADGETT





000
FXUS62 KRAH 180532
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
123 AM EDT SAT APR 18 2015

.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH
TODAY... THEN SHIFT SLOWLY OFFSHORE SUNDAY AS A WARM FRONT
APPROACHES FROM THE SOUTH. THE WARM FRONT WILL MOVE NORTH ON SUNDAY
NIGHT. THIS WILL BE FOLLOWED BY A COLD FRONT THAT WILL PUSH WEST TO
EAST ACROSS CENTRAL NORTH CAROLINA LATE MONDAY INTO MONDAY EVENING.
&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 123 AM SATURDAY...

VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. HOWEVER... VFR TO
MVFR CIGS CAN BE EXPECTED TODAY. THERE IS A CHANCE OF MVFR VSBYS
THIS MORNING WITH A CHANCE OF SHOWERS MAINLY AT KFAY.

A WARM FRONT WILL MOVE NORTH OVER NC SUNDAY. THIS WILL LOWER CIGS
AND VSBYS SUNDAY AS RAIN ARRIVES FROM THE SOUTH DURING THE DAY. IFR
TO LIFR CIGS AND VSBYS WITH RAIN AND FOG ARE EXPECTED LATE SUNDAY
INTO SUNDAY NIGHT.

MONDAY... CIGS WILL BREAK OUT INTO VFR DURING THE MORNING. THERE IS
A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THE COLD FRONT MONDAY
AFTERNOON AND EVENING.

THE OUTLOOK BEYOND MONDAY...
A RETURN TO VFR CONDITIONS IS EXPECTED MONDAY NIGHT THROUGH FRIDAY.



&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...BADGETT




000
FXUS62 KRAH 180155
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
955 PM EDT FRI APR 17 2015

.SYNOPSIS...HIGH PRESSURE WILL EXTEND SOUTHWARD THROUGH OUR AREA
THROUGH SATURDAY. A LOW PRESSURE SYSTEM WILL BEGIN TO AFFECT OUR
AREA SUNDAY THROUGH MONDAY.

&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...KCP
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM





000
FXUS62 KRAH 180155
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
955 PM EDT FRI APR 17 2015

.SYNOPSIS...HIGH PRESSURE WILL EXTEND SOUTHWARD THROUGH OUR AREA
THROUGH SATURDAY. A LOW PRESSURE SYSTEM WILL BEGIN TO AFFECT OUR
AREA SUNDAY THROUGH MONDAY.

&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...KCP
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM




000
FXUS62 KRAH 180155
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
955 PM EDT FRI APR 17 2015

.SYNOPSIS...HIGH PRESSURE WILL EXTEND SOUTHWARD THROUGH OUR AREA
THROUGH SATURDAY. A LOW PRESSURE SYSTEM WILL BEGIN TO AFFECT OUR
AREA SUNDAY THROUGH MONDAY.

&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...KCP
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM





000
FXUS62 KRAH 180155
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
955 PM EDT FRI APR 17 2015

.SYNOPSIS...HIGH PRESSURE WILL EXTEND SOUTHWARD THROUGH OUR AREA
THROUGH SATURDAY. A LOW PRESSURE SYSTEM WILL BEGIN TO AFFECT OUR
AREA SUNDAY THROUGH MONDAY.

&&

.NEAR TERM /TONIGHT/...
AS OF 950 PM FRIDAY...

A WELL-DEFINED SHORTWAVE TROUGH OVER NORTHERN AL/GA WILL MOVE
GENERALLY EAST ACROSS THE SOUTHERN APPALACHIANS...SC...AND FAR
SOUTHERN NC TONIGHT...TO A POSITION INVOF KILM BY 12Z SAT. AN
EXPANSIVE AREA OF SHOWERS WILL ACCOMPANY THIS FEATURE AS IT MOVES
EAST...WITH THE ASSOCIATED HIGHEST PROBABILITY OF RAIN OVER THE
SOUTHERN PIEDMONT/SANDHILLS/SOUTHERN COASTAL PLAIN AFTER
MIDNIGHT...WITH PROGRESSIVELY LOWER CHANCES TOWARD AND ESPECIALLY
NORTH OF HIGHWAY 64. IT APPEARED THAT A COUPLE UPSTREAM  CONVECTIVE
CLUSTERS OVER VA...WHICH INITIATED ALONG A LEE SURFACE TROUGH...MAY
MAINTAIN INTENSITY AS THEY PROPAGATED SOUTHEASTWARD ALONG THEIR
ASSOCIATED OUTFLOW INTO A WEAK INSTABILITY AXIS CENTERED OVER THE
NORTHERN NC PIEDMONT...BUT THAT ACTIVITY HAS MOSTLY DIMINISHED
DURING THE PAST FEW HOURS. SO WHILE A SHOWER OR TWO CANNOT BE
ENTIRELY RULED OUT OVER THE NORTHERN PIEDMONT AS BOTH PAIR OF
OUTFLOW DRIFT SOUTH...THE PROBABILITY OF OCCURRENCE IS QUITE LOW
RELATIVE TO THE INCOMING SHOWERS ASSOCIATED WITH THE AFOREMENTIONED
SHORTWAVE TROUGH. LOWS CLOSE TO CURRENT SURFACE DEWPOINT
TEMPERATURES...MOSTLY IN THE LOWER TO MIDDLE 60S. IF ANY APPRECIABLE
BREAKS IN THE CLOUDS OCCUR...MOST LIKELY OVER THE NORTHERN PIEDMONT
WHERE INFLUENCE FROM THE SHORTWAVE TROUGH AND ASSOCIATED
LIFT/MOISTURE WILL BE LESS PREVALENT...THEN PATCHY FOG WOULD BE
PROBABLE IN THOSE AREAS.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...KCP
NEAR TERM...RAH
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM




000
FXUS62 KRAH 180132
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
932 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERED SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM




000
FXUS62 KRAH 180132
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
932 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERED SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM





000
FXUS62 KRAH 180132
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
932 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERED SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM





000
FXUS62 KRAH 180132
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
932 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERED SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 930 PM FRIDAY...

CONDITIONS ARE VFR ACROSS THE AREA. SHOWERS WILL MOVE ACROSS THE
SOUTHERN PART OF THE AREA OVERNIGHT... PRIMARILY IMPACTING KFAY...
ALTHOUGH THERE IS A CHANCE THE PRECIP COULD BRIEFLY MOVE IN TO KRDU
AND KRWI. CIGS WILL LOWER TO MVFR AFTER 06Z... BEFORE IMPROVING TO
VFR BRIEFLY AFTER 21Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...RAH/MLM




000
FXUS62 KRAH 171906
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
300 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERD SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...

LINGERING MVFR CEILINGS WILL LIFT AND THIN...WITH PREDOMINANT VFR
CEILINGS THIS EVENING AND EARLY TONIGHT. MOIST AIRMASS IN PLACE IN
THE LOW LEVELS WILL PROVIDE FUEL FOR SHOWER DEVELOPMENT AS AN
APPROACHING UPPER WAVE MOVES ACROSS THE AREA OVERNIGHT. EXPECT
SCATTERED SHOWERS TO DEVELOP...AND BECOME MORE NUMEROUS ACROSS THE
SOUTH (FAY) AREA. CEILINGS WILL FALL EVERYWHERE AS WE COOL
DOWN...HOWEVER...WITH WIDESPREAD IFR TO POSSIBLY SOME LIFR CEILINGS
AFTER 06Z. SIMILARLY...EXPECT CLOUDINESS TO HINDER DENSER FOG
DEVELOPMENT...BUT WIDESPREAD MVFR VISIBILITY IS EXPECTED AFTER
MIDNIGHT...WITH PATCHY IFR/LIFR TOWARDS MORNING. CONDITIONS WILL
IMPROVE SLOWLY...WITH MVFR CEILINGS AND VFR VISIBILITY BY LATE
MORNING (14-15Z)...WITH VFR CONDITIONS AFTER 18Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...MLM




000
FXUS62 KRAH 171906
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
300 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...

A MOIST AIRMASS WITH PWS ~1.3 INCHES (90TH PERCENTILE) LINGERS OVER
THE AREA TODAY AND A SHORT WAVE OVER NORTHERN AL THIS AFTERNOON WILL
BE MOVING EAST ACROSS THE AREA TONIGHT. TODAYS MODEL RUNS HAVE
SHIFTED THE PATH OF THIS SYSTEM MORE NORTHERLY...AND ALTHOUGH LOW
LEVEL FORCING WILL BE WEAK...WOULD EXPECT SCATTERD SHOWERS TO BEGIN
BREAKING OUT EARLY TONIGHT ACROSS THE SOUTH WITH SOME INCREASING
COVERAGE AS THE NIGHT PROGRESSES. AS SUCH...WILL HAVE CHANCE POPS
ACROSS THE SOUTH AND SLIGHT CHANCES ACROSS THE NORTH. MINS WILL BE
MILD WITH CLOUD COVERAGE...55 TO 60 NORTH...WITH THE SOUTHERN TIER
LIKELY HOLDING IN THE LOWER 60S.


&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SHOWERS WILL LINGER IN THE MORNING...ESPECIALLY IN THE SOUTHEAST...
AS THE SHORT WAVE MOVES OFFSHORE. COOL AIR ADVECTION IN NORTHEAST
FLOW WILL PROVIDE AN ISENTROPIC SURFACE TO INDUCE WEAK LOW LEVEL
FORCING IN THE SOUTH. MEANWHILE...UPPER RIDGING TRANSITIONS ACROSS
THE AREA DURING THE AFTERNOON TO EARLY OVERNIGHT...WHICH SHOULD BE
ANOTHER AID TO LIMITING CONVECTION LARGELY TO THE SOUTHERN TIER IN
THE AFTERNOON. WILL HAVE CHANCE POPS ACROSS THE FAR SOUTH TO SLIGHT
CHANCE ELSEWHERE. HIGHS WILL HAVE TO BE TONED DOWN DUE TO INCREASING
CLOUD COVERAGE AND WEAK COOL AIR ADVECTION. THICKNESSES SUPPORT A
COUPLE OF DEGREES EITHER SIDE OF 80.

THE UPPER RIDGING SHOULD DAMPEN ACTIVITY OVERNIGHT...BUT A WARM
FRONT WILL BE LIFTING NORTH...WITH H85 FLOW VEERING TO
SOUTHEAST...UPSLOPE...AND INCREASING. EXPECT PARTLY CLOUDY ACROSS
THE NORTH...WITH MORE CLOUDINESS IN THE SOUTH OVERNIGHT...AND COULD
SEE SHOWERS MIGRATE INTO THE FAR SOUTHWEST PIEDMONT BY MORNING. MINS
WILL BE COOLER ACROSS THE NORTH...MID 50S...GRADUATED TO AROUND 60
ACROSS THE SOUTHERN TIER.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...

LINGERING MVFR CEILINGS WILL LIFT AND THIN...WITH PREDOMINANT VFR
CEILINGS THIS EVENING AND EARLY TONIGHT. MOIST AIRMASS IN PLACE IN
THE LOW LEVELS WILL PROVIDE FUEL FOR SHOWER DEVELOPMENT AS AN
APPROACHING UPPER WAVE MOVES ACROSS THE AREA OVERNIGHT. EXPECT
SCATTERED SHOWERS TO DEVELOP...AND BECOME MORE NUMEROUS ACROSS THE
SOUTH (FAY) AREA. CEILINGS WILL FALL EVERYWHERE AS WE COOL
DOWN...HOWEVER...WITH WIDESPREAD IFR TO POSSIBLY SOME LIFR CEILINGS
AFTER 06Z. SIMILARLY...EXPECT CLOUDINESS TO HINDER DENSER FOG
DEVELOPMENT...BUT WIDESPREAD MVFR VISIBILITY IS EXPECTED AFTER
MIDNIGHT...WITH PATCHY IFR/LIFR TOWARDS MORNING. CONDITIONS WILL
IMPROVE SLOWLY...WITH MVFR CEILINGS AND VFR VISIBILITY BY LATE
MORNING (14-15Z)...WITH VFR CONDITIONS AFTER 18Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...MLM
SHORT TERM...MLM
LONG TERM...HARTFIELD
AVIATION...MLM





000
FXUS62 KRAH 171853
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
250 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...

LINGERING MVFR CEILINGS WILL LIFT AND THIN...WITH PREDOMINANT VFR
CEILINGS THIS EVENING AND EARLY TONIGHT. MOIST AIRMASS IN PLACE IN
THE LOW LEVELS WILL PROVIDE FUEL FOR SHOWER DEVELOPMENT AS AN
APPROACHING UPPER WAVE MOVES ACROSS THE AREA OVERNIGHT. EXPECT
SCATTERED SHOWERS TO DEVELOP...AND BECOME MORE NUMEROUS ACROSS THE
SOUTH (FAY) AREA. CEILINGS WILL FALL EVERYWHERE AS WE COOL
DOWN...HOWEVER...WITH WIDESPREAD IFR TO POSSIBLY SOME LIFR CEILINGS
AFTER 06Z. SIMILARLY...EXPECT CLOUDINESS TO HINDER DENSER FOG
DEVELOPMENT...BUT WIDESPREAD MVFR VISIBILITY IS EXPECTED AFTER
MIDNIGHT...WITH PATCHY IFR/LIFR TOWARDS MORNING. CONDITIONS WILL
IMPROVE SLOWLY...WITH MVFR CEILINGS AND VFR VISIBILITY BY LATE
MORNING (14-15Z)...WITH VFR CONDITIONS AFTER 18Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...MLM




000
FXUS62 KRAH 171853
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
250 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 245 PM FRIDAY...

SUN-MON NIGHT: A VERY WET AND POTENTIALLY STORMY PERIOD. THE
NORTHERN STREAM SHORTWAVE TROUGH OVER SW CANADA WILL HAVE PICKED UP
THE OPENING LOW THAT IS NOW OVER THE FOUR CORNERS REGION... WITH THE
FORMER FEATURE AMPLIFYING OVER THE UPPER MIDWEST WHILE THE LATTER
FEATURE IS TOSSED NORTHEASTWARD TOWARD LOWER MI. A BATCH OF MID
LEVEL VORTICITY AND SUBTLE TROUGH NOW OFF THE COAST OF NW MEXICO
WILL TRACK QUICKLY EAST THEN NE WITHIN THE STRONG SUBTROPICAL
FLOW... AND IT IS THE MERGING OF THIS WAVE WITH THE OLD SOUTHWEST
LOW INTO A DISTINCT TROUGH AXIS THAT WILL HELP TRIGGER WIDESPREAD
RAIN OVER NC SUN INTO EARLY MON. THE MODELS HAVE TRENDED STRONGER
WITH THESE TWO MERGED FEATURES AND THEIR RESULTANT TROUGH... AND
THUS ARE STRONGER WITH AN ASSOCIATED SURFACE LOW NEAR THE MO
BOOTHEEL SUN MORNING... EXPECT TO MOVE QUICKLY NORTHWARD THROUGH WRN
MI THROUGH SUN NIGHT. MEANWHILE... THE BACKDOOR FRONT THAT DROPS
SOUTHWARD TOWARD THE NC/VA BORDER -- PROPELLED BY AN INTENSE MID
LEVEL SHORTWAVE TROUGH EXITING NEW ENGLAND AND COLD DENSE SURFACE
HIGH PRESSURE CENTERED OVER SRN QUEBEC PUSHING SOUTHWARD -- NOW
APPEARS LIKELY TO MAKE AT LEAST SOME PROGRESS DOWN THROUGH THE NC
PIEDMONT. AND IT LOOKS LIKE THIS FRONT WILL MERGE WITH THE WEAK
FRONTAL ZONE TO OUR SOUTH AS THE LATTER MOVES NORTHWARD... YIELDING
A STRONGER SURFACE FRONTAL ZONE THROUGH NC BY LATE SUN. CONFIDENCE
IS HIGH THAT WE`LL SEE A STRONG SURGE OF LOW LEVEL GULF- AND
ATLANTIC-SOURCE MOISTURE INTO NC... STARTING FIRST IN SW NC AND
SPREADING ENE SUN/SUN NIGHT IN CONJUNCTION WITH THE PRIMARY LIFT
MECHANISMS FORCING ASCENT... INCLUDING MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE.
MOISTURE SHOULD BE DEEP AND PLENTIFUL WITH PW WELL OVER 200% OF
NORMAL AND A DEEP LCL-TO-0C LAYER NEAR 3.5 KM SUPPORTIVE OF WARM
RAIN PROCESSES... AND A PERIOD OF HEAVY RAIN APPEARS LIKELY. OVERALL
RAINFALL IS EXPECTED TO BE 1-2 INCHES... WITH THE LESSER VALUES EAST
AND HIGHER TOTALS WEST. GIVEN SUCH DEEP LIFT AND ANOMALOUSLY HIGH
MOISTURE CONTENT... AND IF MODELS TREND EVEN WETTER WITH HIGHER QPF
OVER A LARGE AREA... WE MAY NEED TO CONSIDER A FLASH FLOOD WATCH ON
TOMORROW`S SHIFTS. MODEL TIMING HAS BEEN TRENDING A BIT SLOWER WITH
PRECIP ONSET BUT NOW APPEARS TO BE ZEROING IN ON A COMMON
SOLUTION... AND WILL CONTINUE TO RAMP UP POPS TO LIKELY WEST/CHANCE
NE SUN MORNING... GOING TO CATEGORICAL WEST/LIKELY CENTRAL/GOOD
CHANCE EAST SUN AFTERNOON... AND CATEGORICAL EVERYWHERE LATE SUN
AFTERNOON THROUGH SUN NIGHT... BEFORE TRENDING POPS DOWN WSW TO ENE
MON MORNING. WHILE THE LARGE SCALE MODELS DON`T DEPICT MUCH
INSTABILITY AT ALL SUNDAY WITH PRIMARILY MOIST ADIABATIC FORECAST
PROFILES... WE DO HAVE SOME CONCERN ABOUT POCKETS OF CONVECTION AND
AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP ALONG AND NEAR THE
AFOREMENTIONED BACKDOOR/WARM FRONT ACROSS NRN/WRN NC... ESPECIALLY
LATE SUN AFTERNOON THROUGH SUN EVENING AND INTO THE EARLY OVERNIGHT
HOURS... WHEN THE SURFACE FRONT SHOULD BE RETREATING BACK TO THE
NNE... PROVIDING A FOCUS FOR ENHANCED LOW LEVEL VORTICITY. THIS
CONCERN PEAKS SUN EVENING WITH THE COMBINATION OF 30-40 KTS OF DEEP
LAYER SHEAR... AN UPPER DIVERGENCE MAXIMUM OVER THE SRN
APPALACHIANS AND WRN/CENTRAL NC... INCOMING DRIER AIR IN THE MID
LEVELS... AND A 40-50 KT 850 MB JETLET FROM THE SSE... AND FORECAST
SOUNDINGS SHOW A STRONGLY CURVED HODOGRAPH. WILL CONTINUE TO
MONITOR. WILL TAPER POPS DOWN MON MORNING WSW TO ENE AS THE MID
LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE PUSH TO OUR
NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH A PUNCH OF MID
LEVEL DRY AIR ARRIVING FROM THE SW AND FLOW-MID LEVEL FLOW BECOMING
MORE UNIDIRECTIONAL. MUCAPE IS EXPECTED TO REACH 1500-2500 J/KG MON
AFTERNOON (AND COULD BE LOCALLY HIGHER IF WE GET MORE HEATING)...
WITH BULK SHEAR NEAR 30-35 KTS AND SW 850 MB WINDS AROUND 30 KTS.
DYNAMIC FORCING FOR ASCENT WILL HAVE DECREASED BY MON AFTERNOON...
BUT WE`LL STILL BE BENEATH CYCLONIC MID LEVEL FLOW WITH WEAK DPVA...
AND ANOTHER ROUND OF DECENT UPPER DIVERGENCE IN THE LEFT EXIT REGION
OF THE STRAIGHT 140 KT SUBTROPICAL JET ACROSS TX AND THE GULF
STATES. SO STILL EXPECT A FEW STRONG CELLS MON AFTERNOON INTO EARLY
EVENING WITH STRAIGHT LINE WINDS THE PRIMARY THREAT. HIGHS SUN FROM
THE MID 60S TO LOWER 70S WEST OF HIGHWAY 1... AND LOW-MID 70S FROM
HIGHWAY 1 EAST. LOWS UPPER 50S NW TO MID 60S SE. STILL EXPECT HIGHS
IN THE UPPER 70S TO LOWER 80S MON. LOWS MON NIGHT MID 50S NW TO
LOWER 60S SE WITH COLD FRONTAL PASSAGE EXPECTED AFTER MIDNIGHT WITH
DIMINISHING PRECIP CHANCES.

TUE THROUGH FRI: A MAINLY QUIET PERIOD. LARGE AND DEEP MID LEVEL LOW
PRESSURE CENTERED OVER AND NORTH OF THE NRN GREAT LAKES WILL COVER
MUCH OF CENTRAL AND EASTERN NOAM... BRINGING SEASONABLY COOL TEMPS
AS IT SITS AND SPINS THROUGH MID WEEK. HIGH PRESSURE WILL BUILD INTO
OUR AREA FROM THE WEST TUE... PASS OVERHEAD EARLY WED... THEN SHIFT
OFF THE COAST LATE WED INTO THU (GFS IS FASTER THAN THE ECMWF WITH
THIS) WHILE A WARM FRONT MOVES NORTHWARD THROUGH NC. ENERGY
EMANATING OUT OF THE BASE OF DEEP TROUGHING JUST OFF THE WEST COAST
WILL CROSS THE DESERT SOUTHWEST THEN MOVE INTO OUR AREA LATE THU
INTO FRI. WITH A SOUTHERLY LOW LEVEL FLOW ON THE BACK SIDE OF THE
EXITING HIGH... WE SHOULD SEE INCREASING PW AND RETURNING CHANCES
FOR SHOWERS LATE THU INTO FRI... HOWEVER THE MOISTURE INFLUX STILL
DOESN`T LOOK GREAT WITH LIGHT AND DIFFLUENT LOW LEVEL FLOW... SO
WILL KEEP POPS BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST
BELOW NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...

LINGERING MVFR CEILINGS WILL LIFT AND THIN...WITH PREDOMINANT VFR
CEILINGS THIS EVENING AND EARLY TONIGHT. MOIST AIRMASS IN PLACE IN
THE LOW LEVELS WILL PROVIDE FUEL FOR SHOWER DEVELOPMENT AS AN
APPROACHING UPPER WAVE MOVES ACROSS THE AREA OVERNIGHT. EXPECT
SCATTERED SHOWERS TO DEVELOP...AND BECOME MORE NUMEROUS ACROSS THE
SOUTH (FAY) AREA. CEILINGS WILL FALL EVERYWHERE AS WE COOL
DOWN...HOWEVER...WITH WIDESPREAD IFR TO POSSIBLY SOME LIFR CEILINGS
AFTER 06Z. SIMILARLY...EXPECT CLOUDINESS TO HINDER DENSER FOG
DEVELOPMENT...BUT WIDESPREAD MVFR VISIBILITY IS EXPECTED AFTER
MIDNIGHT...WITH PATCHY IFR/LIFR TOWARDS MORNING. CONDITIONS WILL
IMPROVE SLOWLY...WITH MVFR CEILINGS AND VFR VISIBILITY BY LATE
MORNING (14-15Z)...WITH VFR CONDITIONS AFTER 18Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITIES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...MLM





000
FXUS62 KRAH 171652
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1250 PM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...

LINGERING MVFR CEILINGS WILL LIFT AND THIN...WITH PREDOMINANT VFR
CEILINGS THIS EVENING AND EARLY TONIGHT. MOIST AIRMASS IN PLACE IN
THE LOW LEVELS WILL PROVIDE FUEL FOR SHOWER DEVELOPMENT AS AN
APPROACHING UPPER WAVE MOVES ACROSS THE AREA OVERNIGHT. EXPECT
SCATTERED SHOWERS TO DEVELOP...AND BECOME MORE NUMEROUS ACROSS THE
SOUTH (FAY) AREA. CEILINGS WILL FALL EVERYWHERE AS WE COOL
DOWN...HOWEVER...WITH WIDESPREAD IFR TO POSSIBLY SOME LIFR CEILINGS
AFTER 06Z. SIMILARLY...EXPECT CLOUDINESS TO HINDER DENSER FOG
DEVELOPMENT...BUT WIDEPSREAD MVFR VISIBLITY IS EXPECTED AFTER
MIDNIGHT...WITH PATCHY IFR/LIFR TOWARDS MORNING. CONDITIONS WILL
IMPROVE SLOWLY...WITH MVFR CEILINGS AND VFR VISIBILITY BY LATE
MORNING (14-15Z)...WITH VFR CONDITIONS AFTER 18Z.

DRIER AIR WILL EDGE IN BRIEFLY FROM THE NORTH SATURDAY NIGHT...WITH
POSSIBLE MVFR FOG AND VISIBILITES LATE SATURDAY NIGHT. A FRONT
LIFTING NORTH WILL PRODUCE WIDESPREAD HEAVY SHOWERS AND SOME STRONG
THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT...WITH FAIRLY WIDESPREAD
IFR CONDITIONS AND GUSTY WIND IN SHOWERS AND STORMS SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT. SHOWERS AND STORMS WILL BE MORE SCATTERED ON
MONDAY AS A COLD FRONT MOVES THROUGH...WITH PREDOMINANT VFR
CONDITIONS TUESDAY AND WEDNESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...MLM





000
FXUS62 KRAH 171352
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
945 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 171352
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
945 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 171352
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
945 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM FRIDAY...

UPDATE - RESIDUAL WEDGE LINGERING OVER THE PIEDMONT AND ASSOCIATED
HEAVY CLOUDINESS AND LIGHT PRECIP WILL HINDER MAX TEMPS...WILL BE
LOWERING MAXES ACROSS THE AREA...BUT ESPECIALLY THE NORTHWEST WHERE
70 MIGHT BE A STRETCH. WILL ALSO BE INCREASING POPS INTO VERY EARLY
AFTERNOON ALONG AND NORTH OF THE PERIPHERY OF THE BOUNDARY AS WELL
WITH WEAK ISENTROPIC LIFT WHICH WILL BE WEAKENING AFTER 15Z WITH
300K WINDS VEERING TO WESTERLY.

PREVIOUS DISCUSSION

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS/MLM
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 171142
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
740 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 171142
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
740 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 171142
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
740 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT.

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END VFR-MVFR RANGE DURING THE MORNING HOURS. AFTER
14Z...CEILINGS WILL SLOWLY LIFT AND SHOULD BE VFR AT MOST TAF SITES
BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON. SFC
WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 170715
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
314 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 170715
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
314 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 170715
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
314 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 170715
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
314 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM FRIDAY...

SUNDAY THROUGH MONDAY NIGHT: THE LATEST GFS/ECMWF/NAM ARE IN GOOD
AGREEMENT IN SHOWING EXCELLENT MOISTURE TRANSPORT SUNDAY INTO SUNDAY
NIGHT AS A LEAD DISTURBANCE SHIFTS ACROSS THE REGION. PW VALUES ARE
EXPECTED TO INCREASE INTO THE 1.5 TO 1.75 INCH RANGE... WHICH IS
WELL ABOVE NORMAL FOR THIS TIME OF YEAR. MEANWHILE... THE LATEST
ECMWF AND MORESO THE LATEST GFS SHOWS A BACK DOOR FRONT MAKING
BETTER INROADS INTO CENTRAL NC FROM THE NORTH AS A 1025 MB SURFACE
HIGH BUILDS INTO THE AREA FROM NORTH ON SUNDAY MORNING. HOWEVER...
IS STILL UNCLEAR AS TO HOW FAR SOUTH THIS FRONT WILL MAKE IT AND
WHERE A POSSIBLE CAD BOUNDARY MIGHT SET UP. NONETHELESS... ANY
BOUNDARY SHOULD LIFT BACK THROUGH THE AREA/OR SHIFT TO THE NORTH OF
THE AREA SUNDAY NIGHT. HOWEVER... GIVEN THE RATHER STRONG VEERING
LOW LEVEL FLOW... 0-1 KM AND ESPECIALLY 0-3 KM SRH VALUES ARE QUITE
IMPRESSIVE. THANKFULLY AS THE LOW LEVEL FLOW STRENGTHENS AND SRH
VALUES INCREASE THE LATEST MODEL GUIDANCE HAS MINIMAL INSTABILITY AT
BEST... WITH BOTH THE GFS/NAM BUFR SOUNDING SHOWING QUITE MOIST
SOUNDINGS. TAKING A QUICK LOOK AT THE SHERB VALUES... NOT SEEING ANY
VALUES ABOVE 0.5-0.6. VALUES CLOSER TO 1 AND ABOVE WOULD HIGHLIGHT
MORE OF A CONCERN FOR A HIGH SHEAR LOW CAPE SVR/TOR EVENT. WHILE THE
SVR THREAT IS QUITE SMALL (NOT NIL THOUGH)... WE WILL LIKELY SEE
SOME MODERATE TO HEAVY HEAVY RAIN GIVEN THE ABOVE MENTIONED GOOD
MOISTURE TRANSPORT AND HIGH PW`S AND GOOD LIFT. THE BULK OF THE
PRECIP IS EXPECTED LATE SUNDAY INTO SUNDAY NIGHT... WHEN WE COULD
SEE UPWARDS OF 1 TO 2 INCHES OF RAIN.... WITH LOCALIZED HIGHER
AMOUNTS.

HIGH TEMPS WILL BE A CHALLENGE FOR SUNDAY... DEPENDING THE PLACEMENT
OF THE BACKDOOR FRONT AND TIMING OF THE PRECIP AT A GIVEN LOCATION.
FOR NOW WILL SHOW HIGHS IN THE MID TO UPPER 60S NW/N TO THE MID TO
UPPER 70S SE... KEEPING IN MIND OF THE HIGH BUST POTENTIAL.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY NIGHT. WHILE THE STRONGER MID AND LOW LEVEL FLOW
WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY INCREASE
AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE SOUTHWEST
ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD SOME
DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN ISOLATED
TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN ADVANCE
OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE STORMS
(AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST CHANCE
OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT IN
TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA WHERE WE COULD
SEE MLCAPE VALUES OF UP TO 1500 J/KG. HIGHS MONDAY ARE EXPECTED TO
BE IN THE UPPER 70S TO LOWER 80S.. WITH POSSIBLY SOME MID 80S
EAST/SOUTHEAST. LOWS TUESDAY MORNING RANGING FROM THE MID 50S NW TO
AROUND 60 SE.

TUESDAY THROUGH THURSDAY: GENERALLY DRIER WEATHER IS EXPECTED BEHIND
THE FRONT ON TUESDAY THROUGH THURSDAY. HOWEVER... A BROAD MID LEVEL
TROUGH ACROSS THE EAST COAST WILL REMAIN... WITH A MID LEVEL LOW
EXPECTED NEAR THE U.S./CANADIAN BORDER. WHILE CENTRAL NC WILL SEE
THE MAIN MID LEVEL TROUGH AXIS PASS LATE TUESDAY INTO WEDNESDAY
(CURRENTLY DRY)... ITS NOT ENTIRELY OUT OF THE REALM OF POSSIBILITY
THAT WE COULD SEE A FAST MOVING DISTURBANCE IN THE BROAD CYCLONIC
FLOW ALOFT DURING THIS TIME FRAME (TUE-THU) PRODUCE SOME LIGHT
PRECIP. FOR NOW WILL KEEP THE FORECAST DRY AND TEMPS NEAR NORMAL FOR
HIGHS AND LOWS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 170708
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
310 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 170708
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
310 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 170708
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
310 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 170708
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
310 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM FRIDAY...

A NEARLY SATURATED AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE
WILL MAINTAIN EXTENSIVE CLOUDINESS ACROSS CENTRAL NC THIS MORNING.
MAY STILL SEE AN ISOLATED SHOWER OR SPOTS OF DRIZZLE BUT A LIFTING
MECHANISM FOR PRECIP GENERATION LARGELY ABSENT. MAIN FORECAST
CHALLENGE CENTERS ON WHEN/IF WE DISSIPATE ENOUGH OF THE CLOUDS BY
THIS AFTERNOON TO WARM TEMPS BACK TO NEAR NORMAL LEVELS.

AS IS OFTEN THE CASE...RESIDUAL CAD AIR MASS WILL LIKELY BE SLOW TO
ERODE AS NO DISCERNIBLE SCOURING MECHANISM (SUCH AS A COLD FRONT
PASSAGE) NOTED. APPEARS WE WILL HAVE TO RELAY ON MIXING OF DRIER AIR
FROM ALOFT TO ERODE THE CLOUDS...AND PER MODEL SOUNDINGS THIS MAY
TAKE SOME TIME. CLOUD DECK APPEARS TO BE THINNER OVER THE FAR EAST-
NE SO THIS REGION MAY SEE PARTIAL SUN INITIALLY. SIMILARLY...WEAK
DOWNSLOPE COMPONENT TO THE LOW LEVEL FLOW MAY AID TO ERODE THE CLOUD
COVER OVER OUR WESTERN PERIPHERY BY THIS AFTERNOON. THIS SUGGEST
THAT AREAS CLOSEST TO THE HIGHWAY 1 CORRIDOR MAY BE THE LAST TO SEE
PARTIAL SUN SOMETIME THIS AFTERNOON (PROBABLY LATE AFTERNOON).
THUS...MAY SEE A FAIRLY UNIFORM MAX TEMPS FIELD WITH HIGH TEMPS IN
THE MID 70S. TEMPS HIGHLY DEPENDENT ON SOME EROSION OF CLOUD DECK.
IF SKIES REMAIN OVERCAST...MAX TEMPS WILL BE CLOSER TO 70-LOWER 70S.

WHILE BULK OF REGION WILL BE A DRY...A WEAK S/W IN THE NORTHERN
STREAM WILL PASS NORTH OF OUR REGION LATE THIS AFTERNOON. THIS
FEATURE MAY DRAG A WEAK SFC TROUGH INTO OUR REGION. WEAK CONVERGENCE
ALONG THIS FEATURE COUPLED WITH AFTERNOON HEATING MAY TRIGGER AN
ISOLATED SHOWER OR STORM...MAINLY ACROSS THE NORTHERN COUNTIES AND
CLOSER TO THE VA BORDER.

TONIGHT...WHAT PARTIAL CLEARING THAT OCCURS LATER TODAY/THIS EVENING
WILL DETERMINE THE EXTENT OF FOG DEVELOPMENT LATE TONIGHT-EARLY
SATURDAY MORNING. CURRENTLY EXPECT ENOUGH PARTIAL CLEARING ALONG
WITH A SATURATED TOP SOIL TO CAUSE FOG TO DEVELOP MOST LOCATIONS
AFTER MIDNIGHT. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS TIME BUT
COULD SEE POCKETS OF FOG REDUCE THE VISIBILITY TO NEAR ZERO. IF
CLOUD COVER PERSISTS WELL INTO THE AFTERNOON-EVENING HOURS...THEN
FOG PRODUCTION MAY BE LIMITED. MIN TEMPS MILD IN THE UPPER 50S-LOWER
60S.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 310 AM FRIDAY...

SATURDAY...MIXING OF DRIER AIR ALOFT SHOULD AID TO QUICKLY ERODE ANY
FOG/LOW CLOUDS BY MID MORNING SATURDAY. WITH LOW LEVEL THICKNESSES
SEVERAL METERS ABOVE NORMAL...SHOULD SEE TEMPS CLIMB ABOVE 80
DEGREES MOST LOCATIONS WITH SOME SPOTS IN THE SOUTH APPROACHING 85
DEGREES. AFTERNOON INSTABILITY MAY SUPPORT AN ISOLATED SHOWER OR
STORM IN THE FAR SE ASSOCIATED WITH AN INLAND MOVING SEABREEZE.

A WEAK SFC COLD FRONT MAY SLIDE INTO OUR FAR NORTHERN-NE COUNTIES
LATE IN THE DAY SATURDAY OR EARLY EVENING. FRONTAL PASSAGE SHOULD BE
UNEVENTFUL THOUGH COULD SEE SFC DEWPOINTS DIP INTO THE UPPER 40S
OVER THE FAR NORTH-NE SATURDAY EVENING. OTHERWISE...MAY SEE CLOUDS
INCREASE/THICKEN AFTER MIDNIGHT OVER THE FAR SOUTH AND WEST AHEAD OF
THE NEXT APPROACHING LOW PRESSURE SYSTEM. THIS WILL LEAD TO MILD
OVERNIGHT TEMPS IN THE 55-60 DEGREE RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 170514
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
115 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /TONIGHT/...
AS OF 1115 PM THURSDAY...

REGIONAL RAOB DATA INDICATES A WEAKLY UNSTABLE AND SATURATED OR
NEARLY SO LOWEST 10 K FT - SUPPORTIVE OF SCATTERED SHOWERS IN A
WEAKENING REGIME OF ISENTROPIC UPGLIDE ATOP A WEAKENING INVERTED SFC
TROUGH AXIS/WARM FRONT THAT HAS BISECTED CENTRAL NC FROM N-S DURING
THE PAST DAY. ALOFT...WV IMAGERY INDICATED A LEAD SHORTWAVE TROUGH
HAD CROSSED THE MIDDLE ATLANTIC STATES AND WAS MOVING AWAY FROM THE
VA TIDEWATER...WHILE A TRAILING SHEAR AXIS ALOFT WAS MOVING EAST
FROM THE CENTRAL APPALACHIANS. A MORE SIGNIFICANT IMPULSE WAS
EVIDENT LIFTING NE FROM THE LOWER MS VALLEY. THE FORECAST TRACK OF
BOTH THE LEAD SHEAR AXIS ALONG THE APPALACHIANS AND TRAILING AND
MORE SIGNIFICANT IMPULSE FROM THE LOWER MS VALLEY WILL BE FOCUSED TO
OUR NORTH/ACROSS VA...SUCH THAT THE RELATIVE BETTER FORCING FOR
ASCENT AND ASSOCIATED CHANCE OF SHOWERS OVER THE NORTHERN NC
PIEDMONT. RAISED LOW TEMPERATURES GIVEN THE STILL RELATIVELY MILD
TEMPERATURES AROUND 60 DEGREES OR BETTER OVER THE COASTAL
PLAIN...WHICH ARE FORECAST TO CHANGE VERY LITTLE DURING THE
OVERNIGHT...WITH LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60S
EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...RAH
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 170514
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
115 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /TONIGHT/...
AS OF 1115 PM THURSDAY...

REGIONAL RAOB DATA INDICATES A WEAKLY UNSTABLE AND SATURATED OR
NEARLY SO LOWEST 10 K FT - SUPPORTIVE OF SCATTERED SHOWERS IN A
WEAKENING REGIME OF ISENTROPIC UPGLIDE ATOP A WEAKENING INVERTED SFC
TROUGH AXIS/WARM FRONT THAT HAS BISECTED CENTRAL NC FROM N-S DURING
THE PAST DAY. ALOFT...WV IMAGERY INDICATED A LEAD SHORTWAVE TROUGH
HAD CROSSED THE MIDDLE ATLANTIC STATES AND WAS MOVING AWAY FROM THE
VA TIDEWATER...WHILE A TRAILING SHEAR AXIS ALOFT WAS MOVING EAST
FROM THE CENTRAL APPALACHIANS. A MORE SIGNIFICANT IMPULSE WAS
EVIDENT LIFTING NE FROM THE LOWER MS VALLEY. THE FORECAST TRACK OF
BOTH THE LEAD SHEAR AXIS ALONG THE APPALACHIANS AND TRAILING AND
MORE SIGNIFICANT IMPULSE FROM THE LOWER MS VALLEY WILL BE FOCUSED TO
OUR NORTH/ACROSS VA...SUCH THAT THE RELATIVE BETTER FORCING FOR
ASCENT AND ASSOCIATED CHANCE OF SHOWERS OVER THE NORTHERN NC
PIEDMONT. RAISED LOW TEMPERATURES GIVEN THE STILL RELATIVELY MILD
TEMPERATURES AROUND 60 DEGREES OR BETTER OVER THE COASTAL
PLAIN...WHICH ARE FORECAST TO CHANGE VERY LITTLE DURING THE
OVERNIGHT...WITH LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60S
EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...RAH
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 170514
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
115 AM EDT FRI APR 17 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH TONIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SATURDAY. A LOW PRESSURE SYSTEM
WILL BEGIN TO AFFECT OUR AREA SUNDAY...BRINGING A DECENT CHANCE FOR
SHOWERS LATE SUNDAY INTO MONDAY

&&

.NEAR TERM /TONIGHT/...
AS OF 1115 PM THURSDAY...

REGIONAL RAOB DATA INDICATES A WEAKLY UNSTABLE AND SATURATED OR
NEARLY SO LOWEST 10 K FT - SUPPORTIVE OF SCATTERED SHOWERS IN A
WEAKENING REGIME OF ISENTROPIC UPGLIDE ATOP A WEAKENING INVERTED SFC
TROUGH AXIS/WARM FRONT THAT HAS BISECTED CENTRAL NC FROM N-S DURING
THE PAST DAY. ALOFT...WV IMAGERY INDICATED A LEAD SHORTWAVE TROUGH
HAD CROSSED THE MIDDLE ATLANTIC STATES AND WAS MOVING AWAY FROM THE
VA TIDEWATER...WHILE A TRAILING SHEAR AXIS ALOFT WAS MOVING EAST
FROM THE CENTRAL APPALACHIANS. A MORE SIGNIFICANT IMPULSE WAS
EVIDENT LIFTING NE FROM THE LOWER MS VALLEY. THE FORECAST TRACK OF
BOTH THE LEAD SHEAR AXIS ALONG THE APPALACHIANS AND TRAILING AND
MORE SIGNIFICANT IMPULSE FROM THE LOWER MS VALLEY WILL BE FOCUSED TO
OUR NORTH/ACROSS VA...SUCH THAT THE RELATIVE BETTER FORCING FOR
ASCENT AND ASSOCIATED CHANCE OF SHOWERS OVER THE NORTHERN NC
PIEDMONT. RAISED LOW TEMPERATURES GIVEN THE STILL RELATIVELY MILD
TEMPERATURES AROUND 60 DEGREES OR BETTER OVER THE COASTAL
PLAIN...WHICH ARE FORECAST TO CHANGE VERY LITTLE DURING THE
OVERNIGHT...WITH LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60S
EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 115 AM FRIDAY...

VARYING AVIATION CONDITIONS WILL BE THE NORM ACROSS CENTRAL NC TODAY
AND TONIGHT

A MOIST AIR MASS IN THE LOWEST 10K FT OF THE ATMOSPHERE WILL RESULT
IN CEILINGS OF VARYING HEIGHTS. DO EXPECT CEILINGS TO LOWER INTO THE
LOW END MVFR-IFR RANGE DURING THE PRE-DAWN HOURS AS ATMOSPHERE
NOCTURNALLY COOLS/STABILIZES. AFTER 12Z...CEILINGS WILL SLOWLY LIFT
AND SHOULD BE ON THE ORDER OF HIGH END MVFR/LOW END VFR AT MOST TAF
SITES BY 18Z...AND SCATTERED-BROKEN 3500-5000FT BY LATE AFTERNOON.
SFC WINDS WILL BE LIGHT AND VARIABLE.

THE MOIST AIR MASS NEAR THE SURFACE TONIGHT WILL LIKELY CAUSE AREAS
OR WIDESPREAD FOG TO DEVELOP LATE TONIGHT-EARLY SATURDAY
MORNING...RESULTING MVFR/IFR CONDITIONS. THIS FOG AND/OR LOW CLOUDS
SHOULD LIFT AND DISSIPATE 13-15Z SATURDAY. EXPECT VFR CONDITIONS FOR
THE REMAINDER OF SATURDAY. MAY SEE SPOTS OF FOG DEVELOP AGAIN
SATURDAY NIGHT BUT THE FOG SHOULD NOT BE AS PREVALENT AS WHAT IS
EXPECTED TONIGHT/EARLY SATURDAY.

AVIATION CONDITIONS EXPECTED TO TAKE ANOTHER DOWNTURN SUNDAY THROUGH
MONDAY AS A LOW PRESSURE SYSTEM AND ATTENDANT SFC COLD FRONT AFFECTS
OUR REGION. IMPROVING AVIATION CONDITIONS ANTICIPATED FOR TUESDAY.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...RAH
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 170324
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1124 PM EDT THU APR 16 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH FRI NIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SAT.

&&

.NEAR TERM /TONIGHT/...
AS OF 1115 PM THURSDAY...

REGIONAL RAOB DATA INDICATES A WEAKLY UNSTABLE AND SATURATED OR
NEARLY SO LOWEST 10 K FT - SUPPORTIVE OF SCATTERED SHOWERS IN A
WEAKENING REGIME OF ISENTROPIC UPGLIDE ATOP A WEAKENING INVERTED SFC
TROUGH AXIS/WARM FRONT THAT HAS BISECTED CENTRAL NC FROM N-S DURING
THE PAST DAY. ALOFT...WV IMAGERY INDICATED A LEAD SHORTWAVE TROUGH
HAD CROSSED THE MIDDLE ATLANTIC STATES AND WAS MOVING AWAY FROM THE
VA TIDEWATER...WHILE A TRAILING SHEAR AXIS ALOFT WAS MOVING EAST
FROM THE CENTRAL APPALACHIANS. A MORE SIGNIFICANT IMPULSE WAS
EVIDENT LIFTING NE FROM THE LOWER MS VALLEY. THE FORECAST TRACK OF
BOTH THE LEAD SHEAR AXIS ALONG THE APPALACHIANS AND TRAILING AND
MORE SIGNIFICANT IMPULSE FROM THE LOWER MS VALLEY WILL BE FOCUSED TO
OUR NORTH/ACROSS VA...SUCH THAT THE RELATIVE BETTER FORCING FOR
ASCENT AND ASSOCIATED CHANCE OF SHOWERS OVER THE NORTHERN NC
PIEDMONT. RAISED LOW TEMPERATURES GIVEN THE STILL RELATIVELY MILD
TEMPERATURES AROUND 60 DEGREES OR BETTER OVER THE COASTAL
PLAIN...WHICH ARE FORECAST TO CHANGE VERY LITTLE DURING THE
OVERNIGHT...WITH LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60S
EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 806 PM THURSDAY...

24 HOUR TAF PERIOD: CONDITIONS ARE CURRENTLY VFR ACROSS THE EASTERN
PART OF THE AREA (KRDU... KRWI... AND KFAY) AND IFR ACROSS THE
WESTERN PART (KGSO AND KINT). LIGHT SHOWER ACTIVITY WILL CONTINUE TO
DIMINISH ACROSS THE AREA OVERNIGHT. HIGH LOW LEVEL MOISTURE WILL
RESULT IN LOWERING CIGS ACROSS THE AREA OVERNIGHT... AND ALL SITES
WILL BE IFR BY 06Z AND REMAIN THERE UNTIL MID MORNING ON FRIDAY.
CONDITIONS ARE EXPECTED TO GRADUALLY IMPROVE TOMORROW MORNING...
WITH A RETURN TO VFR GENERALLY BETWEEN 15-18Z AT KRWI... KFAY... AND
KRDU AND BETWEEN 21Z-00Z AT KINT AND KGSO.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...RAH
NEAR TERM...RAH
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS




000
FXUS62 KRAH 170324
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1124 PM EDT THU APR 16 2015

.SYNOPSIS...LOW PRESSURE WILL MOVE SLOWLY AWAY FROM THE SOUTHEAST US
COAST THROUGH FRI NIGHT. HIGH PRESSURE WILL OTHERWISE EXTEND ACROSS
THE MIDDLE ATLANTIC STATES THROUGH SAT.

&&

.NEAR TERM /TONIGHT/...
AS OF 1115 PM THURSDAY...

REGIONAL RAOB DATA INDICATES A WEAKLY UNSTABLE AND SATURATED OR
NEARLY SO LOWEST 10 K FT - SUPPORTIVE OF SCATTERED SHOWERS IN A
WEAKENING REGIME OF ISENTROPIC UPGLIDE ATOP A WEAKENING INVERTED SFC
TROUGH AXIS/WARM FRONT THAT HAS BISECTED CENTRAL NC FROM N-S DURING
THE PAST DAY. ALOFT...WV IMAGERY INDICATED A LEAD SHORTWAVE TROUGH
HAD CROSSED THE MIDDLE ATLANTIC STATES AND WAS MOVING AWAY FROM THE
VA TIDEWATER...WHILE A TRAILING SHEAR AXIS ALOFT WAS MOVING EAST
FROM THE CENTRAL APPALACHIANS. A MORE SIGNIFICANT IMPULSE WAS
EVIDENT LIFTING NE FROM THE LOWER MS VALLEY. THE FORECAST TRACK OF
BOTH THE LEAD SHEAR AXIS ALONG THE APPALACHIANS AND TRAILING AND
MORE SIGNIFICANT IMPULSE FROM THE LOWER MS VALLEY WILL BE FOCUSED TO
OUR NORTH/ACROSS VA...SUCH THAT THE RELATIVE BETTER FORCING FOR
ASCENT AND ASSOCIATED CHANCE OF SHOWERS OVER THE NORTHERN NC
PIEDMONT. RAISED LOW TEMPERATURES GIVEN THE STILL RELATIVELY MILD
TEMPERATURES AROUND 60 DEGREES OR BETTER OVER THE COASTAL
PLAIN...WHICH ARE FORECAST TO CHANGE VERY LITTLE DURING THE
OVERNIGHT...WITH LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60S
EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 806 PM THURSDAY...

24 HOUR TAF PERIOD: CONDITIONS ARE CURRENTLY VFR ACROSS THE EASTERN
PART OF THE AREA (KRDU... KRWI... AND KFAY) AND IFR ACROSS THE
WESTERN PART (KGSO AND KINT). LIGHT SHOWER ACTIVITY WILL CONTINUE TO
DIMINISH ACROSS THE AREA OVERNIGHT. HIGH LOW LEVEL MOISTURE WILL
RESULT IN LOWERING CIGS ACROSS THE AREA OVERNIGHT... AND ALL SITES
WILL BE IFR BY 06Z AND REMAIN THERE UNTIL MID MORNING ON FRIDAY.
CONDITIONS ARE EXPECTED TO GRADUALLY IMPROVE TOMORROW MORNING...
WITH A RETURN TO VFR GENERALLY BETWEEN 15-18Z AT KRWI... KFAY... AND
KRDU AND BETWEEN 21Z-00Z AT KINT AND KGSO.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...RAH
NEAR TERM...RAH
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS





000
FXUS62 KRAH 161856
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
252 PM EDT THU APR 16 2015

.SYNOPSIS...SURFACE HIGH PRESSURE TO THE NORTH WILL MOVE OFF OF THE
MID-ATLANTIC COAST TONIGHT AS A LOW CONTINUES TO DEVELOP ALONG THE
SOUTH CAROLINA COAST. COLD AIR DAMMING SCENARIO WILL BREAK DOWN
FRIDAY CREATING WARMER AND DRIER CONDITIONS ACROSS THE AREA.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 PM THURSDAY...

A LOT OF INTERESTING SURFACE FEATURES CONTRIBUTING THE A WIDE ARRAY
OF CONDITIONS ACROSS THE CWA THIS AFTERNOON. FIRST IS THE WEDGE
FRONT ANCHORED IN ACROSS THE WESTERN PIEDMONT AS A RESULT OF THE
HYBRID COLD AIR DAMMING SCENARIO PRESENT BECAUSE OF HIGH PRESSURE
NOW OFF OF THE NY/NEW ENGLAND COAST. THERE IS ALSO WARMER AIR BEING
ADVECTED IN FROM THE EAST AS A COASTAL LOW DEVELOPS OFF OF THE SC/GA
COASTLINE. THE COMBINATION OF THE TWO FEATURES HAS LED TO A VERY
SHARP TEMPERATURE GRADIENT ACROSS THE CWA. IN THE WEST...LOWER
CEILINGS REMAINED LOCKED IN WHEREAS IN THE EAST SOME SCATTERING HAS
OCCURRED AND ALLOWED MAX TEMPERATURES TO TAKE OFF. EXPECTED HIGHS
FOR TODAY WILL END UP IN THE LOW TO MID 50S ACROSS THE NW PIEDMONT
TO THE LOWER 70S EAST OF I-95. LOOKING AT THE PRECIPITATION THREAT
FOR THE REST OF THE DAY...THERE IS A MORE FOCUSED AXIS ALONG US
HIGHWAY 1 AT THE MOMENT AS A RESULT OF LOW LEVEL CONVERGENCE BETWEEN
THE WARM AIR ADVANCING FROM THE EAST (EVIDENT IN SURFACE
OBSERVATIONS) AND THE MORE NORTHERLY FLOW ASSOCIATED WITH THE CAD TO
THE WEST. CONVECTIVE ALLOWING MODELS HAVE PICKED UP ON THIS OVER THE
LAST COUPLE OF HOURS AND HAVE IT DYING OFF AROUND 00Z WITH SOME
PATCHY DRIZZLE THEREAFTER BUT A GENERAL DRYING TREND. OVERNIGHT
TONIGHT EXPECT LOWER CEILINGS TO CREEP IN ONCE AGAIN WHICH WILL HELP
TO EVEN OUT THE TEMPERATURE GRADIENT AND KEEP LOW TEMPS MODERATED
OVERNIGHT. THEREFORE NOT TOO MUCH OF A DROP AT ALL IN THE
WEST...WITH AN ALMOST 20 DROP IN THE EAST. FINAL LOWS SHOULD BOTTOM
OUT LOWER 50S WEST TO MIDDLE 50S EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE SUN... AND MID
70S TO LOWER 80S MON. LOWS AROUND 60 TO THE MID 60S SUN NIGHT AND
MID 50S TO LOWER 60S MON NIGHT... WITH THE FRONT LIKELY NOT COMING
THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS




000
FXUS62 KRAH 161852
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
252 PM EDT THU APR 16 2015

.SYNOPSIS...SURFACE HIGH PRESSURE TO THE NORTH WILL MOVE OFF OF THE
MID-ATLANTIC COAST TONIGHT AS A LOW CONTINUES TO DEVELOP ALONG THE
SOUTH CAROLINA COAST. COLD AIR DAMMING SCENARIO WILL BREAK DOWN
FRIDAY CREATING WARMER AND DRIER CONDITIONS ACROSS THE AREA.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 PM THURSDAY...

A LOT OF INTERESTING SURFACE FEATURES CONTRIBUTING THE A WIDE ARRAY
OF CONDITIONS ACROSS THE CWA THIS AFTERNOON. FIRST IS THE WEDGE
FRONT ANCHORED IN ACROSS THE WESTERN PIEDMONT AS A RESULT OF THE
HYBRID COLD AIR DAMMING SCENARIO PRESENT BECAUSE OF HIGH PRESSURE
NOW OFF OF THE NY/NEW ENGLAND COAST. THERE IS ALSO WARMER AIR BEING
ADVECTED IN FROM THE EAST AS A COASTAL LOW DEVELOPS OFF OF THE SC/GA
COASTLINE. THE COMBINATION OF THE TWO FEATURES HAS LED TO A VERY
SHARP TEMPERATURE GRADIENT ACROSS THE CWA. IN THE WEST...LOWER
CEILINGS REMAINED LOCKED IN WHEREAS IN THE EAST SOME SCATTERING HAS
OCCURRED AND ALLOWED MAX TEMPERATURES TO TAKE OFF. EXPECTED HIGHS
FOR TODAY WILL END UP IN THE LOW TO MID 50S ACROSS THE NW PIEDMONT
TO THE LOWER 70S EAST OF I-95. LOOKING AT THE PRECIPITATION THREAT
FOR THE REST OF THE DAY...THERE IS A MORE FOCUSED AXIS ALONG US
HIGHWAY 1 AT THE MOMENT AS A RESULT OF LOW LEVEL CONVERGENCE BETWEEN
THE WARM AIR ADVANCING FROM THE EAST (EVIDENT IN SURFACE
OBSERVATIONS) AND THE MORE NORTHERLY FLOW ASSOCIATED WITH THE CAD TO
THE WEST. CONVECTIVE ALLOWING MODELS HAVE PICKED UP ON THIS OVER THE
LAST COUPLE OF HOURS AND HAVE IT DYING OFF AROUND 00Z WITH SOME
PATCHY DRIZZLE THEREAFTER BUT A GENERAL DRYING TREND. OVERNIGHT
TONIGHT EXPECT LOWER CEILINGS TO CREEP IN ONCE AGAIN WHICH WILL HELP
TO EVEN OUT THE TEMPERATURE GRADIENT AND KEEP LOW TEMPS MODERATED
OVERNIGHT. THEREFORE NOT TOO MUCH OF A DROP AT ALL IN THE
WEST...WITH AN ALMOST 20 DROP IN THE EAST. FINAL LOWS SHOULD BOTTOM
OUT LOWER 50S WEST TO MIDDLE 50S EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS




000
FXUS62 KRAH 161852
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
252 PM EDT THU APR 16 2015

.SYNOPSIS...SURFACE HIGH PRESSURE TO THE NORTH WILL MOVE OFF OF THE
MID-ATLANTIC COAST TONIGHT AS A LOW CONTINUES TO DEVELOP ALONG THE
SOUTH CAROLINA COAST. COLD AIR DAMMING SCENARIO WILL BREAK DOWN
FRIDAY CREATING WARMER AND DRIER CONDITIONS ACROSS THE AREA.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 PM THURSDAY...

A LOT OF INTERESTING SURFACE FEATURES CONTRIBUTING THE A WIDE ARRAY
OF CONDITIONS ACROSS THE CWA THIS AFTERNOON. FIRST IS THE WEDGE
FRONT ANCHORED IN ACROSS THE WESTERN PIEDMONT AS A RESULT OF THE
HYBRID COLD AIR DAMMING SCENARIO PRESENT BECAUSE OF HIGH PRESSURE
NOW OFF OF THE NY/NEW ENGLAND COAST. THERE IS ALSO WARMER AIR BEING
ADVECTED IN FROM THE EAST AS A COASTAL LOW DEVELOPS OFF OF THE SC/GA
COASTLINE. THE COMBINATION OF THE TWO FEATURES HAS LED TO A VERY
SHARP TEMPERATURE GRADIENT ACROSS THE CWA. IN THE WEST...LOWER
CEILINGS REMAINED LOCKED IN WHEREAS IN THE EAST SOME SCATTERING HAS
OCCURRED AND ALLOWED MAX TEMPERATURES TO TAKE OFF. EXPECTED HIGHS
FOR TODAY WILL END UP IN THE LOW TO MID 50S ACROSS THE NW PIEDMONT
TO THE LOWER 70S EAST OF I-95. LOOKING AT THE PRECIPITATION THREAT
FOR THE REST OF THE DAY...THERE IS A MORE FOCUSED AXIS ALONG US
HIGHWAY 1 AT THE MOMENT AS A RESULT OF LOW LEVEL CONVERGENCE BETWEEN
THE WARM AIR ADVANCING FROM THE EAST (EVIDENT IN SURFACE
OBSERVATIONS) AND THE MORE NORTHERLY FLOW ASSOCIATED WITH THE CAD TO
THE WEST. CONVECTIVE ALLOWING MODELS HAVE PICKED UP ON THIS OVER THE
LAST COUPLE OF HOURS AND HAVE IT DYING OFF AROUND 00Z WITH SOME
PATCHY DRIZZLE THEREAFTER BUT A GENERAL DRYING TREND. OVERNIGHT
TONIGHT EXPECT LOWER CEILINGS TO CREEP IN ONCE AGAIN WHICH WILL HELP
TO EVEN OUT THE TEMPERATURE GRADIENT AND KEEP LOW TEMPS MODERATED
OVERNIGHT. THEREFORE NOT TOO MUCH OF A DROP AT ALL IN THE
WEST...WITH AN ALMOST 20 DROP IN THE EAST. FINAL LOWS SHOULD BOTTOM
OUT LOWER 50S WEST TO MIDDLE 50S EAST.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 250 PM THURSDAY...

FRIDAY AND FRIDAY NIGHT: FRIDAY WILL SEE A DRIER AND WARMER DAY THAN
THE LAST COUPLE AS WEAK ZONAL FLOW ALOFT KEEPS THE PATTERN FAIRLY
MUNDANE. AT THE SURFACE...THE CAD WEDGE WILL BREAK DOWN AS THE
SURFACE HIGH GETS PUSHED OUT TO SHORE AND SETTLES OVER THE WESTERN
ATLANTIC. THE COASTAL LOW WILL MOVE NORTH AND CREATE A CONVERGENCE
ZONE WITH RETURN FLOW FROM THE HIGH THAT WILL REMAIN OFFSHORE...THUS
KEEPING US DRY. THE ONLY THING REALLY TO WATCH OUT FOR WILL BE A
WEAK SURFACE FRONT ASSOCIATED WITH A NORTHERN STREAM LOW PRESSURE
SYSTEM OVER EASTERN CANADA. THIS WILL CAUSE SOME WEAK
INSTABILITY...PARTICULARLY IN THE NORTHWEST PIEDMONT LATER IN THE
DAY ON FRIDAY. CAMS ARE PICKING UP ON THIS AND HAVE A LITTLE BIT OF
CONVECTIVE SHOWER ACTIVITY...MAINLY WEST OF THE TRIAD BUT NOT STRONG
AT ALL AS SB CAPE VALUES ONLY REACH 300 J/KG OR SO AND NO REAL
KINEMATICS TO SPEAK OF WITH SHEAR VALUES LESS THAN 20. RESIDUAL CAD
CLOUD DECKS MAY TAKE A LITTLE TIME TO SCOUR OUT BUT ONCE THEY DO ALL
AREAS SHOULD SEE HIGHS IN THE 70S WITH LOW TO MID 70S NW TO UPPER
70S IN THE SE. CONDITIONS DRY OUT FRIDAY NIGHT AND NO FOG OR LOW
STRATUS IS EXPECTED WITH VERY LIGHT NWLY FLOW. LOW TEMPERATURES IN
THE MID 50S TO NEAR 60 DEGREES. -ELLIS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS





000
FXUS62 KRAH 161843
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S. FRIDAY NIGHT... PARTIAL CLEARING MAY LEAD
TO THE DEVELOPMENT OF FOGGY CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-
60. -WSS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS




000
FXUS62 KRAH 161843
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S. FRIDAY NIGHT... PARTIAL CLEARING MAY LEAD
TO THE DEVELOPMENT OF FOGGY CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-
60. -WSS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS





000
FXUS62 KRAH 161843
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S. FRIDAY NIGHT... PARTIAL CLEARING MAY LEAD
TO THE DEVELOPMENT OF FOGGY CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-
60. -WSS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS




000
FXUS62 KRAH 161843
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S. FRIDAY NIGHT... PARTIAL CLEARING MAY LEAD
TO THE DEVELOPMENT OF FOGGY CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-
60. -WSS

SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...

SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.

TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS





000
FXUS62 KRAH 161808
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
207 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS




000
FXUS62 KRAH 161808
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
207 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS





000
FXUS62 KRAH 161808
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
207 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS





000
FXUS62 KRAH 161808
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
207 PM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...

24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.

LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS




000
FXUS62 KRAH 161504
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1104 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 161504
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1104 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 161504
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1104 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...

VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 161148
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
747 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 317 AM THURSDAY...

HYBRID COLD AIR DAMMING REGIME IN PLACE TO START THE DAY WILL
MAINTAIN OVERCAST SKIES AND PATCHES OF LIGHT RAIN...ESPECIALLY ACROSS
THE PIEDMONT COUNTIES. APPEARS THAT LIGHT RAIN BEING GENERATED BY
THE APPROACH OF A UPPER LEVEL PERTURBATION...SEEN ON WATER VAPOR
IMAGERY LIFTING NE ACROSS THE DEEP SOUTH. THIS FEATURE LIKELY
ENHANCING LOW LEVEL ISENTROPIC UPGLIDE OVER THE PIEDMONT/FOOTHILLS
RESULTING IN THE PATCHY LIGHT RAIN. THIS UPPER LEVEL FEATURE
PROJECTED TO LIFT ACROSS OUR REGION BY EARLY AFTERNOON. IN ITS
WAKE...MID-UPPER LEVEL FLOW WILL BECOME WLY. THIS TYPE OF FLOW TENDS
TO LIMIT PRECIP GENERATION. MEANWHILE...THE PARENT SFC HIGH WILL
DRIFT EAST DURING THE COURSE OF THE DAY...EXERTING LESS INFLUENCE
OVER CENTRAL NC WITH TIME. THUS...SHOULD SEE PRECIP COVERAGE
DECREASE WITH TIME THIS AFTERNOON.

OVERCAST SKIES AND PATCHY LIGHT RAIN WILL LIMIT TEMP RECOVERY OVER
MOST OF THE PIEDMONT. MAX TEMPS THIS AFTERNOON VARY FROM THE 50S IN
THE WEST TO THE 60S IN THE FAR EAST-NE WHERE PRECIP COVERAGE EXPECTED
TO BE LESS.

TONIGHT...OVERCAST SKIES WILL REMAIN THOUGH LACK OF A MECHANISM FOR
PRECIP GENERATION SHOULD RESULT IN JUST ISOLATED PATCHES OF LIGHT
RAIN OR POCKETS OF DRIZZLE. OVERNIGHT TEMPS IN THE LOW-MID 50S.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 161148
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
747 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 317 AM THURSDAY...

HYBRID COLD AIR DAMMING REGIME IN PLACE TO START THE DAY WILL
MAINTAIN OVERCAST SKIES AND PATCHES OF LIGHT RAIN...ESPECIALLY ACROSS
THE PIEDMONT COUNTIES. APPEARS THAT LIGHT RAIN BEING GENERATED BY
THE APPROACH OF A UPPER LEVEL PERTURBATION...SEEN ON WATER VAPOR
IMAGERY LIFTING NE ACROSS THE DEEP SOUTH. THIS FEATURE LIKELY
ENHANCING LOW LEVEL ISENTROPIC UPGLIDE OVER THE PIEDMONT/FOOTHILLS
RESULTING IN THE PATCHY LIGHT RAIN. THIS UPPER LEVEL FEATURE
PROJECTED TO LIFT ACROSS OUR REGION BY EARLY AFTERNOON. IN ITS
WAKE...MID-UPPER LEVEL FLOW WILL BECOME WLY. THIS TYPE OF FLOW TENDS
TO LIMIT PRECIP GENERATION. MEANWHILE...THE PARENT SFC HIGH WILL
DRIFT EAST DURING THE COURSE OF THE DAY...EXERTING LESS INFLUENCE
OVER CENTRAL NC WITH TIME. THUS...SHOULD SEE PRECIP COVERAGE
DECREASE WITH TIME THIS AFTERNOON.

OVERCAST SKIES AND PATCHY LIGHT RAIN WILL LIMIT TEMP RECOVERY OVER
MOST OF THE PIEDMONT. MAX TEMPS THIS AFTERNOON VARY FROM THE 50S IN
THE WEST TO THE 60S IN THE FAR EAST-NE WHERE PRECIP COVERAGE EXPECTED
TO BE LESS.

TONIGHT...OVERCAST SKIES WILL REMAIN THOUGH LACK OF A MECHANISM FOR
PRECIP GENERATION SHOULD RESULT IN JUST ISOLATED PATCHES OF LIGHT
RAIN OR POCKETS OF DRIZZLE. OVERNIGHT TEMPS IN THE LOW-MID 50S.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 161148
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
747 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 317 AM THURSDAY...

HYBRID COLD AIR DAMMING REGIME IN PLACE TO START THE DAY WILL
MAINTAIN OVERCAST SKIES AND PATCHES OF LIGHT RAIN...ESPECIALLY ACROSS
THE PIEDMONT COUNTIES. APPEARS THAT LIGHT RAIN BEING GENERATED BY
THE APPROACH OF A UPPER LEVEL PERTURBATION...SEEN ON WATER VAPOR
IMAGERY LIFTING NE ACROSS THE DEEP SOUTH. THIS FEATURE LIKELY
ENHANCING LOW LEVEL ISENTROPIC UPGLIDE OVER THE PIEDMONT/FOOTHILLS
RESULTING IN THE PATCHY LIGHT RAIN. THIS UPPER LEVEL FEATURE
PROJECTED TO LIFT ACROSS OUR REGION BY EARLY AFTERNOON. IN ITS
WAKE...MID-UPPER LEVEL FLOW WILL BECOME WLY. THIS TYPE OF FLOW TENDS
TO LIMIT PRECIP GENERATION. MEANWHILE...THE PARENT SFC HIGH WILL
DRIFT EAST DURING THE COURSE OF THE DAY...EXERTING LESS INFLUENCE
OVER CENTRAL NC WITH TIME. THUS...SHOULD SEE PRECIP COVERAGE
DECREASE WITH TIME THIS AFTERNOON.

OVERCAST SKIES AND PATCHY LIGHT RAIN WILL LIMIT TEMP RECOVERY OVER
MOST OF THE PIEDMONT. MAX TEMPS THIS AFTERNOON VARY FROM THE 50S IN
THE WEST TO THE 60S IN THE FAR EAST-NE WHERE PRECIP COVERAGE EXPECTED
TO BE LESS.

TONIGHT...OVERCAST SKIES WILL REMAIN THOUGH LACK OF A MECHANISM FOR
PRECIP GENERATION SHOULD RESULT IN JUST ISOLATED PATCHES OF LIGHT
RAIN OR POCKETS OF DRIZZLE. OVERNIGHT TEMPS IN THE LOW-MID 50S.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 160723
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
320 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 317 AM THURSDAY...

HYBRID COLD AIR DAMMING REGIME IN PLACE TO START THE DAY WILL
MAINTAIN OVERCAST SKIES AND PATCHES OF LIGHT RAIN...ESPECIALLY ACROSS
THE PIEDMONT COUNTIES. APPEARS THAT LIGHT RAIN BEING GENERATED BY
THE APPROACH OF A UPPER LEVEL PERTURBATION...SEEN ON WATER VAPOR
IMAGERY LIFTING NE ACROSS THE DEEP SOUTH. THIS FEATURE LIKELY
ENHANCING LOW LEVEL ISENTROPIC UPGLIDE OVER THE PIEDMONT/FOOTHILLS
RESULTING IN THE PATCHY LIGHT RAIN. THIS UPPER LEVEL FEATURE
PROJECTED TO LIFT ACROSS OUR REGION BY EARLY AFTERNOON. IN ITS
WAKE...MID-UPPER LEVEL FLOW WILL BECOME WLY. THIS TYPE OF FLOW TENDS
TO LIMIT PRECIP GENERATION. MEANWHILE...THE PARENT SFC HIGH WILL
DRIFT EAST DURING THE COURSE OF THE DAY...EXERTING LESS INFLUENCE
OVER CENTRAL NC WITH TIME. THUS...SHOULD SEE PRECIP COVERAGE
DECREASE WITH TIME THIS AFTERNOON.

OVERCAST SKIES AND PATCHY LIGHT RAIN WILL LIMIT TEMP RECOVERY OVER
MOST OF THE PIEDMONT. MAX TEMPS THIS AFTERNOON VARY FROM THE 50S IN
THE WEST TO THE 60S IN THE FAR EAST-NE WHERE PRECIP COVERAGE EXPECTED
TO BE LESS.

TONIGHT...OVERCAST SKIES WILL REMAIN THOUGH LACK OF A MECHANISM FOR
PRECIP GENERATION SHOULD RESULT IN JUST ISOLATED PATCHES OF LIGHT
RAIN OR POCKETS OF DRIZZLE. OVERNIGHT TEMPS IN THE LOW-MID 50S.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS




000
FXUS62 KRAH 160723
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
320 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 317 AM THURSDAY...

HYBRID COLD AIR DAMMING REGIME IN PLACE TO START THE DAY WILL
MAINTAIN OVERCAST SKIES AND PATCHES OF LIGHT RAIN...ESPECIALLY ACROSS
THE PIEDMONT COUNTIES. APPEARS THAT LIGHT RAIN BEING GENERATED BY
THE APPROACH OF A UPPER LEVEL PERTURBATION...SEEN ON WATER VAPOR
IMAGERY LIFTING NE ACROSS THE DEEP SOUTH. THIS FEATURE LIKELY
ENHANCING LOW LEVEL ISENTROPIC UPGLIDE OVER THE PIEDMONT/FOOTHILLS
RESULTING IN THE PATCHY LIGHT RAIN. THIS UPPER LEVEL FEATURE
PROJECTED TO LIFT ACROSS OUR REGION BY EARLY AFTERNOON. IN ITS
WAKE...MID-UPPER LEVEL FLOW WILL BECOME WLY. THIS TYPE OF FLOW TENDS
TO LIMIT PRECIP GENERATION. MEANWHILE...THE PARENT SFC HIGH WILL
DRIFT EAST DURING THE COURSE OF THE DAY...EXERTING LESS INFLUENCE
OVER CENTRAL NC WITH TIME. THUS...SHOULD SEE PRECIP COVERAGE
DECREASE WITH TIME THIS AFTERNOON.

OVERCAST SKIES AND PATCHY LIGHT RAIN WILL LIMIT TEMP RECOVERY OVER
MOST OF THE PIEDMONT. MAX TEMPS THIS AFTERNOON VARY FROM THE 50S IN
THE WEST TO THE 60S IN THE FAR EAST-NE WHERE PRECIP COVERAGE EXPECTED
TO BE LESS.

TONIGHT...OVERCAST SKIES WILL REMAIN THOUGH LACK OF A MECHANISM FOR
PRECIP GENERATION SHOULD RESULT IN JUST ISOLATED PATCHES OF LIGHT
RAIN OR POCKETS OF DRIZZLE. OVERNIGHT TEMPS IN THE LOW-MID 50S.

&&

.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...

FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.

FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...

SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.

THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.

SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.

THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.

TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS





000
FXUS62 KRAH 160511
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
110 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 160511
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
110 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 160511
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
110 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...WSS





000
FXUS62 KRAH 160511
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
110 AM EDT THU APR 16 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 110 AM THURSDAY...

AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK.  A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.

SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.

THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.

A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...WSS




000
FXUS62 KRAH 160238
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1038 PM EDT WED APR 15 2015

.SYNOPSIS...A COLD AIR DAMMING WEDGE WILL PERSIST OVER THE REGION
THROUGH THURSDAY...THEN WEAKEN THURSDAY NIGHT INTO FRIDAY AS A WEAK
SURFACE LOW DEVELOPS OFFSHORE THE CAROLINA COAST.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS




000
FXUS62 KRAH 160238
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1038 PM EDT WED APR 15 2015

.SYNOPSIS...A COLD AIR DAMMING WEDGE WILL PERSIST OVER THE REGION
THROUGH THURSDAY...THEN WEAKEN THURSDAY NIGHT INTO FRIDAY AS A WEAK
SURFACE LOW DEVELOPS OFFSHORE THE CAROLINA COAST.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS




000
FXUS62 KRAH 160238
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1038 PM EDT WED APR 15 2015

.SYNOPSIS...A COLD AIR DAMMING WEDGE WILL PERSIST OVER THE REGION
THROUGH THURSDAY...THEN WEAKEN THURSDAY NIGHT INTO FRIDAY AS A WEAK
SURFACE LOW DEVELOPS OFFSHORE THE CAROLINA COAST.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS





000
FXUS62 KRAH 160238
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1038 PM EDT WED APR 15 2015

.SYNOPSIS...A COLD AIR DAMMING WEDGE WILL PERSIST OVER THE REGION
THROUGH THURSDAY...THEN WEAKEN THURSDAY NIGHT INTO FRIDAY AS A WEAK
SURFACE LOW DEVELOPS OFFSHORE THE CAROLINA COAST.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 1030 PM WEDNESDAY...

THE NORTH-SOUTH CORRIDOR OF MODERATE PRECIPITATION WHICH PROGRESSED
EASTWARD ACROSS CENTRAL NC THIS EVENING WAS ASSOCIATED WITH WEAK
DPVA ATTENDANT A SMALL AMPLITUDE DISTURBANCE ALOFT AND MID-LEVEL
WARM ADVECTION /FRONTOGENESIS/. AS OF 02Z...PRECIPITATION ASSOC/W
THE AFOREMENTIONED FORCING MECHANISMS HAS LARGELY SHIFTED INTO
EASTERN NC IN CONCERT WITH THE AFOREMENTIONED DISTURBANCE AND
ATTENDANT CORRIDOR OF ENHANCED MID-LEVEL WARM ADVECTION.
INTERESTINGLY...PRECIPITATION HAS SIGNIFICANTLY WANED IN COVERAGE
THE PAST FEW HOURS...APPARENTLY IN ASSOC/W SUBSIDENCE ATTENDANT A
GRAVITY WAVE PROPAGATING EAST/ESE ACROSS THE SANDHILLS...PER
NUMEROUS SFC OBSERVATIONS INDICATING RAPIDLY FALLING/RISING PRESSURE
AND ANOMALOUS EASTERLY WINDS...GUSTING AS HIGH AS 32 MPH AT THE
LAURINBURG (KMEB) ASOS. GIVEN A THERMODYNAMIC ENVIRONMENT (COLD AIR
DAMMING WEDGE) SUPPORTIVE OF DUCTING...EXPECT THIS FEATURE TO
PERSIST ALL THE WAY TO THE COAST THROUGH 03-05Z.

STRENGTHENING LOW-LEVEL WARM ADVECTION ATOP THE CAD WEDGE OVER
UPSTATE SC AND WESTERN NC HAS ALLOWED ELEVATED SHOWER ACTIVITY TO
DEVELOP ALONG AND WEST OF A LINE EXTENDING SOUTHWARD FROM GREENSBORO
TO WADESBORO AS OF 02Z. EXPECT ELEVATED SHOWERS TO PERSIST WEST OF
THE TRIANGLE OVERNIGHT...PRIMARILY FROM THE TRIAD/SW PIEDMONT
WESTWARD TO THE MOUNTAINS WHERE 925-850 MB WARM ADVECTION WILL BE
STRONGEST AND INCREASING LOW-LEVEL MOISTURE BENEATH A PLUME OF
RELATIVELY STEEPER MID-LEVEL LAPSE RATES (~6.0 C/KM) WILL AID IN
MARGINAL ELEVATED DESTABILIZATION (MUCAPE < 100 J/KG). -VINCENT

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...VINCENT
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS





000
FXUS62 KRAH 160025
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
825 PM EDT WED APR 15 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH THURSDAY NIGHT. A WEAK AREA OF
LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST COAST ON THURSDAY AND
DRIFT NORTHEAST AND MOVE AWAY FROM THE REGION ON FRIDAY. WEAK HIGH
PRESSURE WILL EXTEND INTO THE REGION FOR LATE FRIDAY INTO SATURDAY
BEFORE THE NEXT STORM SYSTEM APPROACHES ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM WEDNESDAY...

A LULL IN PRECIPITATION THIS AFTERNOON AS A SECONDARY WAVE OF DRIER
AIR HAS WORKED INTO THE AREA FROM THE NORTHEAST. THIS HAS LIFTED
CLOUD BASES TO VFR LEVELS AND REDUCED QPF AMOUNTS SIGNIFICANTLY OVER
THE AREA. BACK TO THE WEST A HEAVIER SWATH OF MODERATE PRECIPITATION
AND A FEW EMBEDDED THUNDERSTORMS HAS MOVED INTO UPSTATE SOUTH
CAROLINA. THIS HAS BEEN LARGELY FOCUSED ON THE CONVERGENCE OF THE
SURFACE COLD FRONT AND THE 850 MB TROUGH EXTENDING ACROSS THE AREA.
IT HAS HAD SOME HELP FROM SOME UPPER LEVEL SPEED DIVERGENCE AT 500
MB. THIS BAND OF HEAVIER MOISTURE SHOULD MOVE INTO SOUTHWESTERN
PORTIONS OF THE CWA OVER THE NEXT COUPLE OF HOURS AND TRANSLATE
EASTWARD WITH TIME. WITH THIS RAIN WILL MOST LIKELY COME SOME
LOWERING OF THE CEILINGS BACK TO MVFR LEVELS BUT NOT MUCH LOWER.
TEMPERATURES THIS AFTERNOON HAVE BEEN LARGELY DEPENDENT ON RAINFALL
DISTRIBUTION AND THE OPACITY OF THE CLOUD COVER. BOTH HAVE BEEN LESS
IN THE EAST...WHICH IS WHERE THE WARMEST TEMPS HAVE BEEN. MAINLY MID
TO UPPER 50S IN THE NW AND LOW TO MID 60S IN THE SOUTHEAST. HIGH
RESOLUTION MODELS SHOW RAIN SPREADING THROUGH ALMOST THE ENTIRE CWA
BY 00Z BUT THE INFLUENCES FROM DRIER AIR TO THE NORTHEAST BEGIN TO
ADVANCE SOUTHWESTWARD AND RAIN GETS SHUT OFF DURING THE OVERNIGHT
HOURS FROM NORTHEAST TO SOUTHWEST WITH MOST RAIN REMAINING SOUTH AND
WEST OF I-40 FROM WINSTON-SALEM TO THE COAST THROUGH SUNRISE. COOL
OVERNIGHT WITH LOWS IN THE UPPER 40S BUT POSSIBLY AS LOW AS THE MID
40S IN THE NORTHEAST WHERE THE DRIER AIR RESIDES. SREF PROBABILITIES
INDICATE THAT SUB VFR CLOUD COVER AND VISIBILITIES WILL BE MORE
LIKELY ON WESTERN AND SOUTHERN FRINGES OF THE CWA WITH THE REST OF
THE AREA EXPECTED TO REMAIN VFR. WHILE THIS SEEMS LIKE A DECENT
SCENARIO IT SHOULD BE NOTED THAT FORECAST CONFIDENCE IS LOW GIVEN
THE COLD AIR DAMMING PATTERN AND SOME OF THE OTHER LOWER RESOLUTION
MODELS INDICATING SOME SUB-VFR CEILINGS AND VISIBILITIES OVERNIGHT.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS




000
FXUS62 KRAH 160025
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
825 PM EDT WED APR 15 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH THURSDAY NIGHT. A WEAK AREA OF
LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST COAST ON THURSDAY AND
DRIFT NORTHEAST AND MOVE AWAY FROM THE REGION ON FRIDAY. WEAK HIGH
PRESSURE WILL EXTEND INTO THE REGION FOR LATE FRIDAY INTO SATURDAY
BEFORE THE NEXT STORM SYSTEM APPROACHES ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM WEDNESDAY...

A LULL IN PRECIPITATION THIS AFTERNOON AS A SECONDARY WAVE OF DRIER
AIR HAS WORKED INTO THE AREA FROM THE NORTHEAST. THIS HAS LIFTED
CLOUD BASES TO VFR LEVELS AND REDUCED QPF AMOUNTS SIGNIFICANTLY OVER
THE AREA. BACK TO THE WEST A HEAVIER SWATH OF MODERATE PRECIPITATION
AND A FEW EMBEDDED THUNDERSTORMS HAS MOVED INTO UPSTATE SOUTH
CAROLINA. THIS HAS BEEN LARGELY FOCUSED ON THE CONVERGENCE OF THE
SURFACE COLD FRONT AND THE 850 MB TROUGH EXTENDING ACROSS THE AREA.
IT HAS HAD SOME HELP FROM SOME UPPER LEVEL SPEED DIVERGENCE AT 500
MB. THIS BAND OF HEAVIER MOISTURE SHOULD MOVE INTO SOUTHWESTERN
PORTIONS OF THE CWA OVER THE NEXT COUPLE OF HOURS AND TRANSLATE
EASTWARD WITH TIME. WITH THIS RAIN WILL MOST LIKELY COME SOME
LOWERING OF THE CEILINGS BACK TO MVFR LEVELS BUT NOT MUCH LOWER.
TEMPERATURES THIS AFTERNOON HAVE BEEN LARGELY DEPENDENT ON RAINFALL
DISTRIBUTION AND THE OPACITY OF THE CLOUD COVER. BOTH HAVE BEEN LESS
IN THE EAST...WHICH IS WHERE THE WARMEST TEMPS HAVE BEEN. MAINLY MID
TO UPPER 50S IN THE NW AND LOW TO MID 60S IN THE SOUTHEAST. HIGH
RESOLUTION MODELS SHOW RAIN SPREADING THROUGH ALMOST THE ENTIRE CWA
BY 00Z BUT THE INFLUENCES FROM DRIER AIR TO THE NORTHEAST BEGIN TO
ADVANCE SOUTHWESTWARD AND RAIN GETS SHUT OFF DURING THE OVERNIGHT
HOURS FROM NORTHEAST TO SOUTHWEST WITH MOST RAIN REMAINING SOUTH AND
WEST OF I-40 FROM WINSTON-SALEM TO THE COAST THROUGH SUNRISE. COOL
OVERNIGHT WITH LOWS IN THE UPPER 40S BUT POSSIBLY AS LOW AS THE MID
40S IN THE NORTHEAST WHERE THE DRIER AIR RESIDES. SREF PROBABILITIES
INDICATE THAT SUB VFR CLOUD COVER AND VISIBILITIES WILL BE MORE
LIKELY ON WESTERN AND SOUTHERN FRINGES OF THE CWA WITH THE REST OF
THE AREA EXPECTED TO REMAIN VFR. WHILE THIS SEEMS LIKE A DECENT
SCENARIO IT SHOULD BE NOTED THAT FORECAST CONFIDENCE IS LOW GIVEN
THE COLD AIR DAMMING PATTERN AND SOME OF THE OTHER LOWER RESOLUTION
MODELS INDICATING SOME SUB-VFR CEILINGS AND VISIBILITIES OVERNIGHT.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS





000
FXUS62 KRAH 160025
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
825 PM EDT WED APR 15 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH THURSDAY NIGHT. A WEAK AREA OF
LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST COAST ON THURSDAY AND
DRIFT NORTHEAST AND MOVE AWAY FROM THE REGION ON FRIDAY. WEAK HIGH
PRESSURE WILL EXTEND INTO THE REGION FOR LATE FRIDAY INTO SATURDAY
BEFORE THE NEXT STORM SYSTEM APPROACHES ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM WEDNESDAY...

A LULL IN PRECIPITATION THIS AFTERNOON AS A SECONDARY WAVE OF DRIER
AIR HAS WORKED INTO THE AREA FROM THE NORTHEAST. THIS HAS LIFTED
CLOUD BASES TO VFR LEVELS AND REDUCED QPF AMOUNTS SIGNIFICANTLY OVER
THE AREA. BACK TO THE WEST A HEAVIER SWATH OF MODERATE PRECIPITATION
AND A FEW EMBEDDED THUNDERSTORMS HAS MOVED INTO UPSTATE SOUTH
CAROLINA. THIS HAS BEEN LARGELY FOCUSED ON THE CONVERGENCE OF THE
SURFACE COLD FRONT AND THE 850 MB TROUGH EXTENDING ACROSS THE AREA.
IT HAS HAD SOME HELP FROM SOME UPPER LEVEL SPEED DIVERGENCE AT 500
MB. THIS BAND OF HEAVIER MOISTURE SHOULD MOVE INTO SOUTHWESTERN
PORTIONS OF THE CWA OVER THE NEXT COUPLE OF HOURS AND TRANSLATE
EASTWARD WITH TIME. WITH THIS RAIN WILL MOST LIKELY COME SOME
LOWERING OF THE CEILINGS BACK TO MVFR LEVELS BUT NOT MUCH LOWER.
TEMPERATURES THIS AFTERNOON HAVE BEEN LARGELY DEPENDENT ON RAINFALL
DISTRIBUTION AND THE OPACITY OF THE CLOUD COVER. BOTH HAVE BEEN LESS
IN THE EAST...WHICH IS WHERE THE WARMEST TEMPS HAVE BEEN. MAINLY MID
TO UPPER 50S IN THE NW AND LOW TO MID 60S IN THE SOUTHEAST. HIGH
RESOLUTION MODELS SHOW RAIN SPREADING THROUGH ALMOST THE ENTIRE CWA
BY 00Z BUT THE INFLUENCES FROM DRIER AIR TO THE NORTHEAST BEGIN TO
ADVANCE SOUTHWESTWARD AND RAIN GETS SHUT OFF DURING THE OVERNIGHT
HOURS FROM NORTHEAST TO SOUTHWEST WITH MOST RAIN REMAINING SOUTH AND
WEST OF I-40 FROM WINSTON-SALEM TO THE COAST THROUGH SUNRISE. COOL
OVERNIGHT WITH LOWS IN THE UPPER 40S BUT POSSIBLY AS LOW AS THE MID
40S IN THE NORTHEAST WHERE THE DRIER AIR RESIDES. SREF PROBABILITIES
INDICATE THAT SUB VFR CLOUD COVER AND VISIBILITIES WILL BE MORE
LIKELY ON WESTERN AND SOUTHERN FRINGES OF THE CWA WITH THE REST OF
THE AREA EXPECTED TO REMAIN VFR. WHILE THIS SEEMS LIKE A DECENT
SCENARIO IT SHOULD BE NOTED THAT FORECAST CONFIDENCE IS LOW GIVEN
THE COLD AIR DAMMING PATTERN AND SOME OF THE OTHER LOWER RESOLUTION
MODELS INDICATING SOME SUB-VFR CEILINGS AND VISIBILITIES OVERNIGHT.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS




000
FXUS62 KRAH 160025
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
825 PM EDT WED APR 15 2015

.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH THURSDAY NIGHT. A WEAK AREA OF
LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST COAST ON THURSDAY AND
DRIFT NORTHEAST AND MOVE AWAY FROM THE REGION ON FRIDAY. WEAK HIGH
PRESSURE WILL EXTEND INTO THE REGION FOR LATE FRIDAY INTO SATURDAY
BEFORE THE NEXT STORM SYSTEM APPROACHES ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM WEDNESDAY...

A LULL IN PRECIPITATION THIS AFTERNOON AS A SECONDARY WAVE OF DRIER
AIR HAS WORKED INTO THE AREA FROM THE NORTHEAST. THIS HAS LIFTED
CLOUD BASES TO VFR LEVELS AND REDUCED QPF AMOUNTS SIGNIFICANTLY OVER
THE AREA. BACK TO THE WEST A HEAVIER SWATH OF MODERATE PRECIPITATION
AND A FEW EMBEDDED THUNDERSTORMS HAS MOVED INTO UPSTATE SOUTH
CAROLINA. THIS HAS BEEN LARGELY FOCUSED ON THE CONVERGENCE OF THE
SURFACE COLD FRONT AND THE 850 MB TROUGH EXTENDING ACROSS THE AREA.
IT HAS HAD SOME HELP FROM SOME UPPER LEVEL SPEED DIVERGENCE AT 500
MB. THIS BAND OF HEAVIER MOISTURE SHOULD MOVE INTO SOUTHWESTERN
PORTIONS OF THE CWA OVER THE NEXT COUPLE OF HOURS AND TRANSLATE
EASTWARD WITH TIME. WITH THIS RAIN WILL MOST LIKELY COME SOME
LOWERING OF THE CEILINGS BACK TO MVFR LEVELS BUT NOT MUCH LOWER.
TEMPERATURES THIS AFTERNOON HAVE BEEN LARGELY DEPENDENT ON RAINFALL
DISTRIBUTION AND THE OPACITY OF THE CLOUD COVER. BOTH HAVE BEEN LESS
IN THE EAST...WHICH IS WHERE THE WARMEST TEMPS HAVE BEEN. MAINLY MID
TO UPPER 50S IN THE NW AND LOW TO MID 60S IN THE SOUTHEAST. HIGH
RESOLUTION MODELS SHOW RAIN SPREADING THROUGH ALMOST THE ENTIRE CWA
BY 00Z BUT THE INFLUENCES FROM DRIER AIR TO THE NORTHEAST BEGIN TO
ADVANCE SOUTHWESTWARD AND RAIN GETS SHUT OFF DURING THE OVERNIGHT
HOURS FROM NORTHEAST TO SOUTHWEST WITH MOST RAIN REMAINING SOUTH AND
WEST OF I-40 FROM WINSTON-SALEM TO THE COAST THROUGH SUNRISE. COOL
OVERNIGHT WITH LOWS IN THE UPPER 40S BUT POSSIBLY AS LOW AS THE MID
40S IN THE NORTHEAST WHERE THE DRIER AIR RESIDES. SREF PROBABILITIES
INDICATE THAT SUB VFR CLOUD COVER AND VISIBILITIES WILL BE MORE
LIKELY ON WESTERN AND SOUTHERN FRINGES OF THE CWA WITH THE REST OF
THE AREA EXPECTED TO REMAIN VFR. WHILE THIS SEEMS LIKE A DECENT
SCENARIO IT SHOULD BE NOTED THAT FORECAST CONFIDENCE IS LOW GIVEN
THE COLD AIR DAMMING PATTERN AND SOME OF THE OTHER LOWER RESOLUTION
MODELS INDICATING SOME SUB-VFR CEILINGS AND VISIBILITIES OVERNIGHT.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM WEDNESDAY...

AS HIGH PRESSURE MOVES EASTWARD INTO A MORE FAVORABLE POSITION FOR
HYBRID DAMMING ON THURSDAY MORNING...MODELS ALSO INDICATE THE
DEVELOPMENT OF A COASTAL LOW OFF OF SOUTH CAROLINA. THE COMBINATION
OF THE TWO SUGGESTS A VERY SHARP FRONTAL BOUNDARY EARLY BUT AS THE
DAY PROGRESSES A THIRD PLAYER WILL BE A STRONGER LOW PRESSURE SYSTEM
MOVING ACROSS NORTHERN QUEBEC. THIS LOW...ALONG WITH A SHORTWAVE
WEST OF THE APPALACHIANS WILL HELP PUSH THE HIGH SOUTHEASTWARD
THROUGH THE DAY...MOVING FROM A MORE HYBRID TO AN IN-SITU DAMMING
SCENARIO. IN THE PROCESS HOWEVER...THE INFLUENCE OF THE HIGH SHUTS
OFF PRECIPITATION IN THE NORTHEAST THROUGH THE MORNING HOURS WITH
ONLY LIGHT SCATTERED RAIN EXPECTED DURING THE AFTERNOON. SO BEST
CHANCES FOR RAIN WILL AGAIN BE IN THE SOUTHWEST...SPURRED ON BY
ISENTROPIC LIFT THAT WILL BE MOST PREVALENT DURING THE MORNING HOURS
AND THEN LESS SO IN THE AFTERNOON. WHILE CONDITIONS WILL BE CLOUDY
AND THERE WILL BE CHANCES FOR RAIN MOST OF THE DAY...QPF VALUES
SHOULD BE VERY LOW...NAMELY LESS THAN A TENTH OF AN INCH.
TEMPERATURES WILL FOLLOW THE TYPICAL CAD PATTERN WITH LOWEST MAX
TEMPS IN THE WEST (MID 50S) WITH MIDDLE 60S EAST OF I-95.
PRECIPITATION IS EXPECTED TO WIND DOWN AFTER SUNSET BUT CONDITIONS
WILL REMAIN CLOUDY THROUGH THURSDAY NIGHT. LOWS IN THE LOW TO MID
50S NW TO SE.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 210 PM WEDNESDAY...

FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON
THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM
BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE
ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC
AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE
CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE
MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE
MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL
SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES
LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT.
WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR
LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY
WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH
DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW
ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL
MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST
SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750
J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT
CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID
EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO
AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING
PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE
WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH
THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE
SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC
RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW
STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN
CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH
A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE
EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE
TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS
SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND
CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE
STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR
FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH
PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A
LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY
SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S
TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO
LOWER 60S.

FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE
AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN
MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP
WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN
OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES...
DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES...
ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON
INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND
GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC...
AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY
RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD
END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A
MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS
SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND
SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT
CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN
HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE
TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST
EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED
DRY FOR NOW. -GIH

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 823 PM WEDNESDAY...

24 HOUR TAF PERIOD: AREA OF MODERATE TO HEAVY RAIN IS MOVING OFF TO
THE EAST... AND WILL CONTINUE TO IMPACT KRDU... KRWI... AND KFAY FOR
THE NEXT FEW HOURS. PRECIP SHOULD BECOME LIGHTER AND MORE SCATTERED
IN NATURE THROUGH THE OVERNIGHT HOURS. CIGS ARE VFR ACROSS THE
AREA... THOUGH MODELS ARE INDICATING THAT THEY COULD DIP TO MVFR
WHERE LOW LEVEL MOISTURE REMAINS HIGHER... AT KGSO... KINT... AND
KFAY OVERNIGHT AND INTO TOMORROW. RAIN CHANCES WILL DIMINISH THROUGH
THE DAY TOMORROW.

LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE
CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A
FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE
RETURN TO VFR CONDITIONS ON TUESDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BLAES
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...RAH/ELLIS





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