[top]
000
FXUS61 KRLX 210724
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
324 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST MONDAY. COLD FRONT ARRIVES
MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE SOME
MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING TIGHTENING
UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H M H H H H H H H H H
HTS CONSISTENCY H H H H L H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H M M M H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KRLX 210645
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
238 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST MONDAY. COLD FRONT ARRIVES
MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE SOME
MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING TIGHTENING
UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H M H H H H H H H
HTS CONSISTENCY H H H M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY
NEAR TERM...RPY
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...RPY
[top]
000
FXUS61 KILN 210559
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
159 AM EDT MON MAY 21 2012
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OF THE REGION TONIGHT. A WEAK COLD
FRONT AND LOW PRESSURE CENTER WILL MOVE EAST THROUGH THE AREA ON
MONDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THIS
DISTURBANCE WILL REMAIN JUST SOUTHWEST OF THE REGION THROUGH THE
MIDDLE OF THE WEEK...WITH WARM AND DRY CONDITIONS MOVING IN FOR
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FA REMAINS UNDER THE WAINING INFLUENCE OF SFC AND UPPER RIDGING
THIS EVENING. SO UPPER LEVEL MOISTURE FROM ALBERTO THAT WORKED
ACROSS THE APPALACHIANS CONTINUES TO AFFECT THE ERN COUNTIES.
A CDFNT WILL APPROACH FROM THE W OVERNIGHT. THIS WILL RESULT IN AN
INCREASE IN CLOUDS FROM THE IL/IN FOR THE WRN COUNTIES. FOR THE
ERN COUNTIES THE CI SHOULD BECOME SCT BY SUNRISE.
TEMPERATURES HAVE COOLED IN THE E WITH SUNSET...SO KNOCKED A DEGREE
OR SO OFF THE LOWS TONIGHT. IN THE W LEFT THE LOWS ALONE DUE TO
THE INCREASING MOISTURE AND CLOUDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS A SSW-TO-NNE FRONT MOVES EAST ACROSS THE REGION MONDAY...A WEAK
SURFACE LOW WILL ALSO DEVELOP ALONG THE BOUNDARY. MUCH OF THE
MOISTURE AND PRECIPITATION WILL BE PRESENT IMMEDIATELY ALONG OR
EVEN SLIGHTLY BEHIND THIS FEATURE (AT LEAST AS DELINEATED BY THE
WIND SHIFT). BUILDING INSTABILITY WILL BE THE ONE FACTOR THE FRONT
HAS GOING FOR IT...WITH AROUND 1000 J/KG MLCAPE EXPECTED.
HOWEVER...FRONTAL FORCING IS NOT STRONG...AND WIND SHEAR IS WEAK
TO VIRTUALLY NON-EXISTENT. THUS...SEVERE WEATHER IS NOT
EXPECTED...AND EVEN THE COVERAGE OF PRECIPITATION IS SOMEWHAT IN
QUESTION. POPS HAVE BEEN LIMITED TO 50-PERCENT FOR NOW. SOME
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE GIVEN THE SLOW STORM
MOTIONS EXPECTED.
THE OVERALL PATTERN WILL MOVE VERY SLOWLY THROUGH THE NEXT DAY OR
TWO. AN UPPER TROUGH WILL CLOSE OFF INTO A LOW NEAR NORTH
CAROLINA...WITH ENOUGH MOISTURE AND A WEAK SURFACE LOW NEAR WEST
VIRGINIA HELPING TO KEEP A CHANCE OF PRECIPITATION IN THE FORECAST
FOR THE SE CWA ON TUESDAY.
THE TEMPERATURE FORECAST FOR MONDAY IS NON-DIURNAL AND BASED ON
THE FRONTAL PASSAGE...WHICH SHOULD BEGIN TO COOL TEMPERATURES IN
THE WEST BY 18Z. WARM CONDITIONS ARE POSSIBLE IN THE
SOUTHEAST (WHERE TEMPERATURES WILL BE APPROXIMATELY DIURNAL)...THOUGH
INCREASING CLOUDS WILL KEEP CONDITIONS SLIGHTLY COOLER THAN
SUNDAY. WITH LOW LEVEL MOISTURE STILL IN PLACE...SOME CLOUDS WILL
BE AROUND TO START TUESDAY...WHICH WILL COMBINE WITH THE WEAK COLD
ADVECTION BEHIND THE FRONT TO RESULT IN A SIZABLE TEMPERATURE
DROP FROM MONDAY TO TUESDAY (VALUES NEAR OR SLIGHTLY BELOW NORMAL).
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
CENTER OF UPR LVL CLOSED LOW IS EXPECTED TO BE SOUTHEAST OF THE
REGION ON WEDNESDAY. THE PROXIMITY OF THE LOW TO OUR SE ZONES MAY
SKIM THIS AREA WITH ENOUGH MOISTURE TO POP AN AFTERNOON SHOWER OR
THUNDERSTORM. OTHERWISE...THE REMAINDER OF THE AREA SHOULD BE DRY.
TEMPERATURES WILL GENERALLY BE IN THE UPPER 70S.
FOR THE REMAINDER OF THE EXTENDED...HAVE TAKEN A BLEND OF THE 00Z
ECMWF AND NCEP/HPC AS THE GFS IS NOT THE PREFERRED SOLUTION. THE
ECMWF SHOWS A MORE PRONOUNCED UPR LVL RIDGE BUILDING INTO THE OHIO
VALLEY WHILE THE GFS IS FARTHER SOUTH AND MORE SUPPRESSED.
FOR WEDNESDAY NIGHT INTO THURSDAY...UPR LVL CLOSED LOW WILL SLOWLY
PUSH OFF TO THE EAST AS AN UPR LVL RIDGE BEGINS TO BUILD INTO THE
WEST. DRY WEATHER IS EXPECTED WITH MODERATING TEMPERATURES INTO THE
80S.
FOR THURSDAY NIGHT INTO SATURDAY...UPR LVL RIDGE WILL CONTINUE TO
BUILD INTO THE OHIO VALLEY. A COLD FRONT WILL TRY TO NUDGE SOUTHWARD
CLOSE TO THE FAR NRN ZONES FRIDAY AFTERNOON AND EVENING. THIS MAY
POP A SHOWER OR THUNDERSTORM DURING THIS TIME FRAME OTHERWISE DRY
WEATHER WILL PREVAIL. UPR LVL RIDGE IS EXPECTED TO STRENGTHEN
SATURDAY NIGHT INTO NEXT WEEK. THIS SETUP WILL BRING DRY WEATHER AND
HOT TEMPERATURES FOR LATE MAY. HIGHS SHOULD EVENTUALLY CLIMB INTO
THE LOWER 90S WITH LOWS RANGING IN THE 65 TO 70 DEGREE RANGE. THESE
TEMPERATURES WILL BE MORE LIKE MID JULY TO MID AUGUST VALUES. THE
UNOFFICIAL KICK OFF TO SUMMER SHOULD HAVE A SUMMER FEEL TO IT.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL START OUT THE TAF PERIOD. A COLD FRONT IS
CURRENTLY LOCATED ACROSS INDIANA. THIS FEATURE WILL MOVE THROUGH
THE TAF SITES TODAY. SHOWER AND THUNDERSTORM ACTIVITY WILL BE SLOW
TO MOVE INTO THE AREA TODAY AND WILL MAINLY BE POST FRONTAL. VSBYS MAY BE
REDUCED TO THE MVFR RANGE WITH SOME OF THE HEAVIER SHOWER AND
THUNDERSTORM ACTIVITY. PRECIPITATION WILL TAPER OFF ACROSS THE
AREA DURING THE EVENING HOURS.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...NOVAK
[top]
000
FXUS61 KCLE 210552
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
152 AM EDT MON MAY 21 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FOR 930 PM UPDATE...FORECAST TO CONTINUE AS PLANNED WITH ONLY MINOR
CHANGES FOR CURRENT CONDITIONS TO GRIDS. DRY LOW LEVELS SHOULD KEEP
RAIN WEST OF AREA THROUGH DAYBREAK ALTHOUGH FIRST BAND OF WEAKENING
SHRA/TSRA COULD MAKE A RUN TOWARD THE WESTERN OH BORDER AROUND
MIDNIGHT BEFORE DISSIPATING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.
THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.
MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.
FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THIS MORNING... THEN SHOWERS
AND SCATTERED THUNDERSTORMS WILL BEGIN TO DEVELOP. THE LINE OF
SHOWERS/STORMS ASSOCIATED WITH A COLD FRONT CROSSING INDIANA WILL
WORK ACROSS NORTHWEST OHIO THIS MORNING INTO THE AFTERNOON. IT IS
ALSO LIKELY THAT NEW SHOWERS AND STORMS WILL POP UP IN ADVANCE OF
THE FRONT ACROSS NE OH/NW PA DURING THE MID TO LATE AFTERNOON. IT
MAY TAKE UNTIL LATE IN THE DAY OR TONIGHT FOR THE ACTIVITY TO
REACH KYNG AND KERI. WINDS WILL SHIFT TO THE NNW AFTER THE FRONT
AND A WIND SHIFT WILL ALSO OCCUR AT KCLE AND KERI FROM THE NORTH
OFF LAKE ERIE EARLY THIS AFTERNOON. MVFR VISIBILITIES WILL OCCUR
WITH SOME OF THE HEAVIER SHOWERS/STORMS.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
THUNDERSTORMS TONIGHT INTO TUESDAY. EARLY MORNING FOG/HAZE MAY
ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.
THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KOSARIK
MARINE...KIELTYKA
[top]
000
FXUS61 KPBZ 210545
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
145 AM EDT MON MAY 21 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST AS LOW PRESSURE MOVES UP THE
EAST COAST AND A COLD FRONT APPROACHES FROM THE GREAT LAKES. THE BEST
CHANCE FOR SHOWERS WILL BE ON TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION WILL BE PUSHED OFF
TO THE NORTHEAST TOWARD DAYBREAK. WITH LOW PRESSURE OVER VIRGINIA
SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD ACROSS THE
RIDGES TODAY WHILE A COLD FRONT NEAR THE INDIAN AND OHIO BORDER
MOVES SLOWLY EAST. CHANCE POPS AS THE DAY PROGRESSES WITH HIGHER
POPS ACROSS EASTERN 2/3RDS OF REGION. LOWERED MAX TEMPS A COUPLE
DEGREES FRO PREVIOUS FORECAST AS CLOUDS WILL BE INCREASING A BIT
QUICKER.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROF AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. WITH UPPER TROUGH
HANGING BACK ACROSS REGION AND AVAILABLE LOW LEVEL MOISTURE CHANCE
POPS FOR THE MOST PART THROUGH THE PERIOD WITH A TIME OF LIKELY
POPS ACROSS THE RIDGES. ENOUGH INSTABILITY FOR AN AFTERNOON
THUNDERSTORM BUT NOTHING WIDESPREAD. WITH CLOUDS AND SHOWERS
TEMPERATURES FORECAST TO BE ONLY A BIT ABOVE NORMAL WITH MILD
OVERNIGHT LOWS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. THIS WILL MAKE ISOLATED SHOWERS AND THUNDERSTORMS WITH
MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS LATE THIS AFTERNOON
AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE NOT
MENTIONED IN THE TAFS AT THIS POINT.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS TONIGHT
THROUGH WEDNESDAY. SURFACE DEWPOINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 210536
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
121 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE...NO SIGNIFICANT CHANGES MADE TO CURRENT FORECAST.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H M H H H H H H H
HTS CONSISTENCY H H H M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KPBZ 210513
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
113 AM EDT MON MAY 21 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST AS LOW PRESSURE MOVES UP THE
EAST COAST AND A COLD FRONT APPROACHES FROM THE GREAT LAKES. THE BEST
CHANCE FOR SHOWERS WILL BE ON TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION WILL BE PUSHED OFF
TO THE NORTHEAST TOWARD DAYBREAK. WITH LOW PRESSURE OVER VIRGINIA
SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD ACROSS THE
RIDGES TODAY WHILE A COLD FRONT NEAR THE INDIAN AND OHIO BORDER
MOVES SLOWLY EAST. CHANCE POPS AS THE DAY PROGRESSES WITH HIGHER
POPS ACROSS EASTERN 2/3RDS OF REGION. LOWERED MAX TEMPS A COUPLE
DEGREES FRO PREVIOUS FORECAST AS CLOUDS WILL BE INCREASING A BIT
QUICKER.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROF AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. WITH UPPER TROUGH
HANGING BACK ACROSS REGION AND AVAILABLE LOW LEVEL MOISTURE CHANCE
POPS FOR THE MOST PART THROUGH THE PERIOD WITH A TIME OF LIKELY
POPS ACROSS THE RIDGES. ENOUGH INSTABILITY FOR AN AFTERNOON
THUNDERSTORM BUT NOTHING WIDESPREAD. WITH CLOUDS AND SHOWERS
TEMPERATURES FORECAST TO BE ONLY A BIT ABOVE NORMAL WITH MILD
OVERNIGHT LOWS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KILN 210237
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1037 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OF THE REGION TONIGHT. A WEAK COLD
FRONT AND LOW PRESSURE CENTER WILL MOVE EAST THROUGH THE AREA ON
MONDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THIS
DISTURBANCE WILL REMAIN JUST SOUTHWEST OF THE REGION THROUGH THE
MIDDLE OF THE WEEK...WITH WARM AND DRY CONDITIONS MOVING IN FOR
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FA REMAINS UNDER THE WAINING INFLUENCE OF SFC AND UPPER RIDGING
THIS EVENING. SO UPPER LEVEL MOISTURE FROM ALBERTO THAT WORKED
ACROSS THE APPALACHIANS CONTINUES TO AFFECT THE ERN COUNTIES.
A CDFNT WILL APPROACH FROM THE W OVERNIGHT. THIS WILL RESULT IN AN
INCREASE IN CLOUDS FROM THE IL/IN FOR THE WRN COUNTIES. FOR THE
ERN COUNTIES THE CI SHOULD BECOME SCT BY SUNRISE.
TEMPERATURES HAVE COOLED IN THE E WITH SUNSET...SO KNOCKED A DEGREE
OR SO OFF THE LOWS TONIGHT. IN THE W LEFT THE LOWS ALONE DUE TO
THE INCREASING MOISTURE AND CLOUDS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS A SSW-TO-NNE FRONT MOVES EAST ACROSS THE REGION MONDAY...A WEAK
SURFACE LOW WILL ALSO DEVELOP ALONG THE BOUNDARY. MUCH OF THE
MOISTURE AND PRECIPITATION WILL BE PRESENT IMMEDIATELY ALONG OR
EVEN SLIGHTLY BEHIND THIS FEATURE (AT LEAST AS DELINEATED BY THE
WIND SHIFT). BUILDING INSTABILITY WILL BE THE ONE FACTOR THE FRONT
HAS GOING FOR IT...WITH AROUND 1000 J/KG MLCAPE EXPECTED.
HOWEVER...FRONTAL FORCING IS NOT STRONG...AND WIND SHEAR IS WEAK
TO VIRTUALLY NON-EXISTENT. THUS...SEVERE WEATHER IS NOT
EXPECTED...AND EVEN THE COVERAGE OF PRECIPITATION IS SOMEWHAT IN
QUESTION. POPS HAVE BEEN LIMITED TO 50-PERCENT FOR NOW. SOME
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE GIVEN THE SLOW STORM
MOTIONS EXPECTED.
THE OVERALL PATTERN WILL MOVE VERY SLOWLY THROUGH THE NEXT DAY OR
TWO. AN UPPER TROUGH WILL CLOSE OFF INTO A LOW NEAR NORTH
CAROLINA...WITH ENOUGH MOISTURE AND A WEAK SURFACE LOW NEAR WEST
VIRGINIA HELPING TO KEEP A CHANCE OF PRECIPITATION IN THE FORECAST
FOR THE SE CWA ON TUESDAY.
THE TEMPERATURE FORECAST FOR MONDAY IS NON-DIURNAL AND BASED ON
THE FRONTAL PASSAGE...WHICH SHOULD BEGIN TO COOL TEMPERATURES IN
THE WEST BY 18Z. WARM CONDITIONS ARE POSSIBLE IN THE
SOUTHEAST (WHERE TEMPERATURES WILL BE APPROXIMATELY DIURNAL)...THOUGH
INCREASING CLOUDS WILL KEEP CONDITIONS SLIGHTLY COOLER THAN
SUNDAY. WITH LOW LEVEL MOISTURE STILL IN PLACE...SOME CLOUDS WILL
BE AROUND TO START TUESDAY...WHICH WILL COMBINE WITH THE WEAK COLD
ADVECTION BEHIND THE FRONT TO RESULT IN A SIZABLE TEMPERATURE
DROP FROM MONDAY TO TUESDAY (VALUES NEAR OR SLIGHTLY BELOW NORMAL).
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
CENTER OF UPR LVL CLOSED LOW IS EXPECTED TO BE SOUTHEAST OF THE
REGION ON WEDNESDAY. THE PROXIMITY OF THE LOW TO OUR SE ZONES MAY
SKIM THIS AREA WITH ENOUGH MOISTURE TO POP AN AFTERNOON SHOWER OR
THUNDERSTORM. OTHERWISE...THE REMAINDER OF THE AREA SHOULD BE DRY.
TEMPERATURES WILL GENERALLY BE IN THE UPPER 70S.
FOR THE REMAINDER OF THE EXTENDED...HAVE TAKEN A BLEND OF THE 00Z
ECMWF AND NCEP/HPC AS THE GFS IS NOT THE PREFERRED SOLUTION. THE
ECMWF SHOWS A MORE PRONOUNCED UPR LVL RIDGE BUILDING INTO THE OHIO
VALLEY WHILE THE GFS IS FARTHER SOUTH AND MORE SUPPRESSED.
FOR WEDNESDAY NIGHT INTO THURSDAY...UPR LVL CLOSED LOW WILL SLOWLY
PUSH OFF TO THE EAST AS AN UPR LVL RIDGE BEGINS TO BUILD INTO THE
WEST. DRY WEATHER IS EXPECTED WITH MODERATING TEMPERATURES INTO THE
80S.
FOR THURSDAY NIGHT INTO SATURDAY...UPR LVL RIDGE WILL CONTINUE TO
BUILD INTO THE OHIO VALLEY. A COLD FRONT WILL TRY TO NUDGE SOUTHWARD
CLOSE TO THE FAR NRN ZONES FRIDAY AFTERNOON AND EVENING. THIS MAY
POP A SHOWER OR THUNDERSTORM DURING THIS TIME FRAME OTHERWISE DRY
WEATHER WILL PREVAIL. UPR LVL RIDGE IS EXPECTED TO STRENGTHEN
SATURDAY NIGHT INTO NEXT WEEK. THIS SETUP WILL BRING DRY WEATHER AND
HOT TEMPERATURES FOR LATE MAY. HIGHS SHOULD EVENTUALLY CLIMB INTO
THE LOWER 90S WITH LOWS RANGING IN THE 65 TO 70 DEGREE RANGE. THESE
TEMPERATURES WILL BE MORE LIKE MID JULY TO MID AUGUST VALUES. THE
UNOFFICIAL KICK OFF TO SUMMER SHOULD HAVE A SUMMER FEEL TO IT.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
SFC AND H5 RIDGING WILL RETREAT SLOWLY TO THE E TONIGHT...ALLOWING
H5 TROF AND SFC CDFNT TO PUSH INTO THE REGION. MODELS ARE IN PRETTY
GOOD AGREEMENT IN PUSHING THE CDFNT TO NR THE OH/IN BORDER BY 12Z
MONDAY. MUCH OF THE LIFT WILL BE POST FRONT AS THE H5 TROF LAGS
BEHINDS THE FNT...SO DIDNT REALLY GO WITH PCPN AHEAD OF THE FNT.
POST FRONTAL...PUT IN VCTS THEN ADDED A 2 HOUR TEMPO WHEN THE
BEST CHANCE WOULD BE AT EACH AIRPORT. THAT ENDED UP BEING 16-18Z
IN THE WRN TAFS AND 18-21Z IN THE ERN TAFS. KEPT THE CIGS VFR
THROUGH THE TAF PERIOD...BUT BROUGHT THE VSBYS DOWN TO MVFR.
SOME FOG TO DEVELOP AT LUK AGAIN TONIGHT...BUT EXPECT IT TO STAY
MVFR.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
000
FXUS61 KRLX 210233
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1033 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
1030 PM UPDATE...NO SIGNIFICANT CHANGES MADE TO CURRENT FORECAST.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EDT 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H H H M H H H
HTS CONSISTENCY H H H H H H H M M M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H M M M H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KPBZ 210138
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
938 PM EDT SUN MAY 20 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.
TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.
BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 210124
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
924 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FOR 930 PM UPDATE...FORECAST TO CONTINUE AS PLANNED WITH ONLY MINOR
CHANGES FOR CURRENT CONDITIONS TO GRIDS. DRY LOW LEVELS SHOULD KEEP
RAIN WEST OF AREA THROUGH DAYBREAK ALTHOUGH FIRST BAND OF WEAKENING
SHRA/TSRA COULD MAKE A RUN TOWARD THE WESTERN OH BORDER AROUND
MIDNIGHT BEFORE DISSIPATING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.
THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.
MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.
FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL CONTINUE INTO AT LEAST LATE MONDAY MORNING.
A COLD FRONT WILL BE MOVING INTO NW OHIO AROUND SUNRISE AND WILL
BRING A WIND SHIFT TO THE WEST AND EVENTUALLY NORTHWEST IN ITS
WAKE. THIS BOUNDARY MAY PRODUCE ENOUGH CONVERGENCE TO INCREASE THE
CHANCES OF THUNDERSTORMS FOR LOCATIONS NEAR AND EAST OF A KCLE TO
KMFD LINE BY MID TO LATE AFTERNOON. MOISTURE LEVELS ARE NOT THAT
IMPRESSIVE SO THE COVERAGE OF THE THUNDERSTORMS WILL LIKELY BE
LIMITED AND MAY ACTUALLY OCCUR WEST OF THE INITIAL WIND SHIFT.
THE STORMS THAT DEVELOP WILL HAVE THE POTENTIAL OF SOME GUSTY WINDS.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
THUNDERSTORMS MONDAY EVENING INTO TUESDAY. EARLY MORNING FOG/HAZE
MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.
THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/ADAMS
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...KIELTYKA
000
FXUS61 KILN 210022
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
822 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OF THE REGION TONIGHT. A WEAK COLD
FRONT AND LOW PRESSURE CENTER WILL MOVE EAST THROUGH THE AREA ON
MONDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THIS
DISTURBANCE WILL REMAIN JUST SOUTHWEST OF THE REGION THROUGH THE
MIDDLE OF THE WEEK...WITH WARM AND DRY CONDITIONS MOVING IN FOR
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE AIR MASS OVER THE CWA TODAY IS RATHER WARM...BUT ALSO FAIRLY
DRY IN ALL BUT THE SOUTHWEST CORNER. THE UNCAPPED INSTABILITY TO
THE SW OF THE CWA HAS BEEN ENOUGH TO DEVELOP SOME POP-UP SHOWERS
AND STORMS...BUT THIS IS LOOKING INCREASINGLY UNLIKELY TO OCCUR
NEAR OUR BORDERS. SO...THE DRY FORECAST FOR THIS EVENING WILL BE
CONTINUED.
AHEAD OF THE APPROACHING FRONT...TEMPERATURES AND DEWPOINTS WILL
BEGIN TO INCREASE SOMEWHAT OVERNIGHT. THIS WILL LEAD TO STEADY OR
RISING TEMPERATURES IN THE WESTERN HALF OF THE CWA BEFORE DAWN. AS
A RESULT...MIN TEMPERATURES ARE GENERALLY ABOVE GUIDANCE NUMBERS
AND MUCH CLOSER TO RAW MODEL DATA (USED THE NAM12 AS A STARTING
POINT...THOUGH THERE WAS NO SIGNIFICANT DISAGREEMENT ON THE
SITUATION BETWEEN MODELS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS A SSW-TO-NNE FRONT MOVES EAST ACROSS THE REGION MONDAY...A WEAK
SURFACE LOW WILL ALSO DEVELOP ALONG THE BOUNDARY. MUCH OF THE
MOISTURE AND PRECIPITATION WILL BE PRESENT IMMEDIATELY ALONG OR
EVEN SLIGHTLY BEHIND THIS FEATURE (AT LEAST AS DELINEATED BY THE
WIND SHIFT). BUILDING INSTABILITY WILL BE THE ONE FACTOR THE FRONT
HAS GOING FOR IT...WITH AROUND 1000 J/KG MLCAPE EXPECTED.
HOWEVER...FRONTAL FORCING IS NOT STRONG...AND WIND SHEAR IS WEAK
TO VIRTUALLY NON-EXISTENT. THUS...SEVERE WEATHER IS NOT
EXPECTED...AND EVEN THE COVERAGE OF PRECIPITATION IS SOMEWHAT IN
QUESTION. POPS HAVE BEEN LIMITED TO 50-PERCENT FOR NOW. SOME
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE GIVEN THE SLOW STORM
MOTIONS EXPECTED.
THE OVERALL PATTERN WILL MOVE VERY SLOWLY THROUGH THE NEXT DAY OR
TWO. AN UPPER TROUGH WILL CLOSE OFF INTO A LOW NEAR NORTH
CAROLINA...WITH ENOUGH MOISTURE AND A WEAK SURFACE LOW NEAR WEST
VIRGINIA HELPING TO KEEP A CHANCE OF PRECIPITATION IN THE FORECAST
FOR THE SE CWA ON TUESDAY.
THE TEMPERATURE FORECAST FOR MONDAY IS NON-DIURNAL AND BASED ON
THE FRONTAL PASSAGE...WHICH SHOULD BEGIN TO COOL TEMPERATURES IN
THE WEST BY 18Z. WARM CONDITIONS ARE POSSIBLE IN THE
SOUTHEAST (WHERE TEMPERATURES WILL BE APPROXIMATELY DIURNAL)...THOUGH
INCREASING CLOUDS WILL KEEP CONDITIONS SLIGHTLY COOLER THAN
SUNDAY. WITH LOW LEVEL MOISTURE STILL IN PLACE...SOME CLOUDS WILL
BE AROUND TO START TUESDAY...WHICH WILL COMBINE WITH THE WEAK COLD
ADVECTION BEHIND THE FRONT TO RESULT IN A SIZABLE TEMPERATURE
DROP FROM MONDAY TO TUESDAY (VALUES NEAR OR SLIGHTLY BELOW NORMAL).
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
CENTER OF UPR LVL CLOSED LOW IS EXPECTED TO BE SOUTHEAST OF THE
REGION ON WEDNESDAY. THE PROXIMITY OF THE LOW TO OUR SE ZONES MAY
SKIM THIS AREA WITH ENOUGH MOISTURE TO POP AN AFTERNOON SHOWER OR
THUNDERSTORM. OTHERWISE...THE REMAINDER OF THE AREA SHOULD BE DRY.
TEMPERATURES WILL GENERALLY BE IN THE UPPER 70S.
FOR THE REMAINDER OF THE EXTENDED...HAVE TAKEN A BLEND OF THE 00Z
ECMWF AND NCEP/HPC AS THE GFS IS NOT THE PREFERRED SOLUTION. THE
ECMWF SHOWS A MORE PRONOUNCED UPR LVL RIDGE BUILDING INTO THE OHIO
VALLEY WHILE THE GFS IS FARTHER SOUTH AND MORE SUPPRESSED.
FOR WEDNESDAY NIGHT INTO THURSDAY...UPR LVL CLOSED LOW WILL SLOWLY
PUSH OFF TO THE EAST AS AN UPR LVL RIDGE BEGINS TO BUILD INTO THE
WEST. DRY WEATHER IS EXPECTED WITH MODERATING TEMPERATURES INTO THE
80S.
FOR THURSDAY NIGHT INTO SATURDAY...UPR LVL RIDGE WILL CONTINUE TO
BUILD INTO THE OHIO VALLEY. A COLD FRONT WILL TRY TO NUDGE SOUTHWARD
CLOSE TO THE FAR NRN ZONES FRIDAY AFTERNOON AND EVENING. THIS MAY
POP A SHOWER OR THUNDERSTORM DURING THIS TIME FRAME OTHERWISE DRY
WEATHER WILL PREVAIL. UPR LVL RIDGE IS EXPECTED TO STRENGTHEN
SATURDAY NIGHT INTO NEXT WEEK. THIS SETUP WILL BRING DRY WEATHER AND
HOT TEMPERATURES FOR LATE MAY. HIGHS SHOULD EVENTUALLY CLIMB INTO
THE LOWER 90S WITH LOWS RANGING IN THE 65 TO 70 DEGREE RANGE. THESE
TEMPERATURES WILL BE MORE LIKE MID JULY TO MID AUGUST VALUES. THE
UNOFFICIAL KICK OFF TO SUMMER SHOULD HAVE A SUMMER FEEL TO IT.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SFC AND H5 RIDGING WILL RETREAT SLOWLY TO THE E TONIGHT...ALLOWING
H5 TROF AND SFC CDFNT TO PUSH INTO THE REGION. MODELS ARE IN PRETTY
GOOD AGREEMENT IN PUSHING THE CDFNT TO NR THE OH/IN BORDER BY 12Z
MONDAY. MUCH OF THE LIFT WILL BE POST FRONT AS THE H5 TROF LAGS
BEHINDS THE FNT...SO DIDNT REALLY GO WITH PCPN AHEAD OF THE FNT.
POST FRONTAL...PUT IN VCTS THEN ADDED A 2 HOUR TEMPO WHEN THE
BEST CHANCE WOULD BE AT EACH AIRPORT. THAT ENDED UP BEING 16-18Z
IN THE WRN TAFS AND 18-21Z IN THE ERN TAFS. KEPT THE CIGS VFR
THROUGH THE TAF PERIOD...BUT BROUGHT THE VSBYS DOWN TO MVFR.
SOME FOG TO DEVELOP AT LUK AGAIN TONIGHT...BUT EXPECT IT TO STAY
MVFR.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
000
FXUS61 KCLE 202341
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
741 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FOR 630 PM UPDATE...ONLY CHANGE WAS TO RAISE LOWS A DEG OR TWO WEST
TWO-THIRDS DUE TO EXPECTED INCREASED CLOUDS AND SOUTH WINDS AHEAD OF
COLD FRONT THAT ARRIVES ON MON. DRY LOW LEVELS SHOULD KEEP RAIN WEST
OF AREA THROUGH DAYBREAK ALTHOUGH FIRST BAND OF WEAKENING SHRA/TSRA
COULD MAKE A RUN TOWARD THE WESTERN OH BORDER BY MIDNIGHT BEFORE
DISSIPATING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.
THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.
MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.
FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL CONTINUE INTO AT LEAST LATE MONDAY MORNING.
A COLD FRONT WILL BE MOVING INTO NW OHIO AROUND SUNRISE AND WILL
BRING A WIND SHIFT TO THE WEST AND EVENTUALLY NORTHWEST IN ITS
WAKE. THIS BOUNDARY MAY PRODUCE ENOUGH CONVERGENCE TO INCREASE THE
CHANCES OF THUNDERSTORMS FOR LOCATIONS NEAR AND EAST OF A KCLE TO
KMFD LINE BY MID TO LATE AFTERNOON. MOISTURE LEVELS ARE NOT THAT
IMPRESSIVE SO THE COVERAGE OF THE THUNDERSTORMS WILL LIKELY BE
LIMITED AND MAY ACTUALLY OCCUR WEST OF THE INITIAL WIND SHIFT.
THE STORMS THAT DEVELOP WILL HAVE THE POTENTIAL OF SOME GUSTY WINDS.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
THUNDERSTORMS MONDAY EVENING INTO TUESDAY. EARLY MORNING FOG/HAZE
MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.
THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...KIELTYKA
000
FXUS61 KPBZ 202327
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
727 PM EDT SUN MAY 20 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.
TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.
BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 202325 CCA
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
724 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
715 PM UPDATE...NO MAJOR CHANGES MADE TO ONGOING FORECAST. A COUPLE
OF SHOWERS WHICH HAVE FORMED OVER THE CENTRAL HIGH TERRAIN SHOULD
DISSIPATE OVER THE COURSE OF THE NEXT HOUR OR SO WITH THE LOSS OF
DAYTIME HEATING.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H M H
HTS CONSISTENCY H H H H H H H H H M M M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KRLX 202324
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
724 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
715 PM UPDATE...NO MAJOR CHANGES MADE TO ONGOING FORECAST. A COUPLE
OF SHOWERS WHICH HAVE FORMED OVER THE CENTRAL HIGH TERRAIN SHOULD
DISSIPATE OVER THE COURSE OF THE NEXT HOUR OR SO WITH THE LOSS OF
DAYTIME HEATING.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H M H
HTS CONSISTENCY H H H H H H H H H M M M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KCLE 202217
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
616 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FOR 630 PM UPDATE...ONLY CHANGE WAS TO RAISE LOWS A DEG OR TWO WEST
TWO-THIRDS DUE TO EXPECTED INCREASED CLOUDS AND SOUTH WINDS AHEAD OF
COLD FRONT THAT ARRIVES ON MON. DRY LOW LEVELS SHOULD KEEP RAIN WEST
OF AREA THROUGH DAYBREAK ALTHOUGH FIRST BAND OF WEAKENING SHRA/TSRA
COULD MAKE A RUN TOWARD THE WESTERN OH BORDER BY MIDNIGHT BEFORE
DISSIPATING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.
THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.
MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.
FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE
WATCHED.
TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.
THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/ADAMS
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
000
FXUS61 KPBZ 202215
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
615 PM EDT SUN MAY 20 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.
TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.
BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY
MORNING. SOME EARLY MORNING VISIBILITY RESTRICTIONS EXPECTED
ACROSS EASTERN OH IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR.
MID CLOUDS DECK WILL WORK INTO THE AREA MONDAY.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 202030
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
430 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST OVER THE CENTRAL
MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED HEAT SOURCE
EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS EXPECTED FOR THE PERIOD...OUTSIDE OF SOME
PATCHY MVFR RIVER VALLEY FOG DEVELOPING AFTER 09Z. ANY FOG THAT
DEVELOPS WILL BURN OFF BY 13Z FOR A RETURN OF VFR CONDITIONS AREA
WIDE. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 18Z
MONDAY AS A COLD FRONT APPROACHES FROM THE WEST...AND AN UPPER LOW
APPROACHES FROM THE EAST. EXPECT GRADUALLY LOWERING/THICKENING OF
CIGS AFTER 12Z MONDAY AS THESE TWO SYSTEMS APPROACH...ALTHOUGH
CIGS WILL REMAIN ABOVE VFR.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. SHOWERS/STORMS ON MONDAY MAY DEVELOP QUICKER THAN
FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...SL
000
FXUS61 KILN 202008
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
408 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OF THE REGION TONIGHT. A WEAK COLD
FRONT AND LOW PRESSURE CENTER WILL MOVE EAST THROUGH THE AREA ON
MONDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THIS
DISTURBANCE WILL REMAIN JUST SOUTHWEST OF THE REGION THROUGH THE
MIDDLE OF THE WEEK...WITH WARM AND DRY CONDITIONS MOVING IN FOR
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE AIR MASS OVER THE CWA TODAY IS RATHER WARM...BUT ALSO FAIRLY
DRY IN ALL BUT THE SOUTHWEST CORNER. THE UNCAPPED INSTABILITY TO
THE SW OF THE CWA HAS BEEN ENOUGH TO DEVELOP SOME POP-UP SHOWERS
AND STORMS...BUT THIS IS LOOKING INCREASINGLY UNLIKELY TO OCCUR
NEAR OUR BORDERS. SO...THE DRY FORECAST FOR THIS EVENING WILL BE
CONTINUED.
AHEAD OF THE APPROACHING FRONT...TEMPERATURES AND DEWPOINTS WILL
BEGIN TO INCREASE SOMEWHAT OVERNIGHT. THIS WILL LEAD TO STEADY OR
RISING TEMPERATURES IN THE WESTERN HALF OF THE CWA BEFORE DAWN. AS
A RESULT...MIN TEMPERATURES ARE GENERALLY ABOVE GUIDANCE NUMBERS
AND MUCH CLOSER TO RAW MODEL DATA (USED THE NAM12 AS A STARTING
POINT...THOUGH THERE WAS NO SIGNIFICANT DISAGREEMENT ON THE
SITUATION BETWEEN MODELS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS A SSW-TO-NNE FRONT MOVES EAST ACROSS THE REGION MONDAY...A WEAK
SURFACE LOW WILL ALSO DEVELOP ALONG THE BOUNDARY. MUCH OF THE
MOISTURE AND PRECIPITATION WILL BE PRESENT IMMEDIATELY ALONG OR
EVEN SLIGHTLY BEHIND THIS FEATURE (AT LEAST AS DELINEATED BY THE
WIND SHIFT). BUILDING INSTABILITY WILL BE THE ONE FACTOR THE FRONT
HAS GOING FOR IT...WITH AROUND 1000 J/KG MLCAPE EXPECTED.
HOWEVER...FRONTAL FORCING IS NOT STRONG...AND WIND SHEAR IS WEAK
TO VIRTUALLY NON-EXISTENT. THUS...SEVERE WEATHER IS NOT
EXPECTED...AND EVEN THE COVERAGE OF PRECIPITATION IS SOMEWHAT IN
QUESTION. POPS HAVE BEEN LIMITED TO 50-PERCENT FOR NOW. SOME
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE GIVEN THE SLOW STORM
MOTIONS EXPECTED.
THE OVERALL PATTERN WILL MOVE VERY SLOWLY THROUGH THE NEXT DAY OR
TWO. AN UPPER TROUGH WILL CLOSE OFF INTO A LOW NEAR NORTH
CAROLINA...WITH ENOUGH MOISTURE AND A WEAK SURFACE LOW NEAR WEST
VIRGINIA HELPING TO KEEP A CHANCE OF PRECIPITATION IN THE FORECAST
FOR THE SE CWA ON TUESDAY.
THE TEMPERATURE FORECAST FOR MONDAY IS NON-DIURNAL AND BASED ON
THE FRONTAL PASSAGE...WHICH SHOULD BEGIN TO COOL TEMPERATURES IN
THE WEST BY 18Z. WARM CONDITIONS ARE POSSIBLE IN THE
SOUTHEAST (WHERE TEMPERATURES WILL BE APPROXIMATELY DIURNAL)...THOUGH
INCREASING CLOUDS WILL KEEP CONDITIONS SLIGHTLY COOLER THAN
SUNDAY. WITH LOW LEVEL MOISTURE STILL IN PLACE...SOME CLOUDS WILL
BE AROUND TO START TUESDAY...WHICH WILL COMBINE WITH THE WEAK COLD
ADVECTION BEHIND THE FRONT TO RESULT IN A SIZABLE TEMPERATURE
DROP FROM MONDAY TO TUESDAY (VALUES NEAR OR SLIGHTLY BELOW NORMAL).
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
CENTER OF UPR LVL CLOSED LOW IS EXPECTED TO BE SOUTHEAST OF THE
REGION ON WEDNESDAY. THE PROXIMITY OF THE LOW TO OUR SE ZONES MAY
SKIM THIS AREA WITH ENOUGH MOISTURE TO POP AN AFTERNOON SHOWER OR
THUNDERSTORM. OTHERWISE...THE REMAINDER OF THE AREA SHOULD BE DRY.
TEMPERATURES WILL GENERALLY BE IN THE UPPER 70S.
FOR THE REMAINDER OF THE EXTENDED...HAVE TAKEN A BLEND OF THE 00Z
ECMWF AND NCEP/HPC AS THE GFS IS NOT THE PREFERRED SOLUTION. THE
ECMWF SHOWS A MORE PRONOUNCED UPR LVL RIDGE BUILDING INTO THE OHIO
VALLEY WHILE THE GFS IS FARTHER SOUTH AND MORE SUPPRESSED.
FOR WEDNESDAY NIGHT INTO THURSDAY...UPR LVL CLOSED LOW WILL SLOWLY
PUSH OFF TO THE EAST AS AN UPR LVL RIDGE BEGINS TO BUILD INTO THE
WEST. DRY WEATHER IS EXPECTED WITH MODERATING TEMPERATURES INTO THE
80S.
FOR THURSDAY NIGHT INTO SATURDAY...UPR LVL RIDGE WILL CONTINUE TO
BUILD INTO THE OHIO VALLEY. A COLD FRONT WILL TRY TO NUDGE SOUTHWARD
CLOSE TO THE FAR NRN ZONES FRIDAY AFTERNOON AND EVENING. THIS MAY
POP A SHOWER OR THUNDERSTORM DURING THIS TIME FRAME OTHERWISE DRY
WEATHER WILL PREVAIL. UPR LVL RIDGE IS EXPECTED TO STRENGTHEN
SATURDAY NIGHT INTO NEXT WEEK. THIS SETUP WILL BRING DRY WEATHER AND
HOT TEMPERATURES FOR LATE MAY. HIGHS SHOULD EVENTUALLY CLIMB INTO
THE LOWER 90S WITH LOWS RANGING IN THE 65 TO 70 DEGREE RANGE. THESE
TEMPERATURES WILL BE MORE LIKE MID JULY TO MID AUGUST VALUES. THE
UNOFFICIAL KICK OFF TO SUMMER SHOULD HAVE A SUMMER FEEL TO IT.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
LIGHT SOUTHEAST WINDS WILL PREVAIL AHEAD OF THE NEXT FRONT THAT IS
EXPECTED TO CROSS THE REGION EARLY ON MONDAY. LOOKING AT THE SAME
SYSTEM NOW...THERE IS VERY LITTLE ACTIVITY NOTED AND THE EXPECTED
LARGER SCALE FORCING WITH THE FRONT WILL BE WELL NORTH AND WELL
SOUTHWEST OF THE OHIO VALLEY. I DO NOT SEE THE LARGE THREAT FOR
THUNDERSTORMS ON MONDAY WITH THIS FROPA. IT SHOULD BE MORE
SCATTERED SHOWERS OF A GENERALLY LIGHT NATURE. THE FINER DETAILS
ARE STILL IN QUESTION BUT ALMOST ALL OF THE MODELS ARE HINTING
THAT THIS FROPA WILL HAVE DISJOINTED PRECIPIATION WITH IT AND NOT
A LINE OF SHOWERS THAT HITS EVERYONE IN ITS PATH.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...FRANKS
000
FXUS61 KCLE 201940
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
340 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HIGH PRESSURE CENTERED OVER NY AND PA WILL CONTINUE TO KEEP
CONDITIONS DRY ACROSS THE FORECAST AREA TONIGHT. EXPECTING SOME
CIRRUS CLOUDS TO CONTINUE ACROSS THE AREA WITH LITTLE IMPACT.
TEMPS WILL BE TRICKY WITH RADIATING CONDITIONS LIKELY ACROSS THE
COOLER SPOTS INCLUDING INTERIOR NW PA...BUT WESTERN AREAS MAY SEE
MILDER LOWS GIVEN INCREASING MOISTURE AND SOUTHERLY FLOW
DEVELOPING/OR INCREASING DURING THE OVERNIGHT. USED MAINLY MAV
TEMPS WITH SOME LOCAL ADJUSTMENTS. OVERALL WENT WITH MID TO UPPER
50S ACROSS THE EASTERN 2/3 OF THE AREA AND LOWS AROUND 60 ACROSS
THE FAR WEST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.
THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.
MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.
FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE WATCHED.
TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.
THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
000
FXUS61 KPBZ 201921
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
321 PM EDT SUN MAY 20 2012
.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL ARRIVE ON TUESDAY BEFORE CONDITIONS SLOWLY DRY OUT.
&&
.NEAR TERM /THROUGH MONDAY/...
ALTHOUGH TROPICAL STORM ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS
BEEN THE MAIN WEATHER FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM
OFF THE VIRGINIA COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE
LOCAL FORECAST FOR THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY
OVER THE REGION WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH
THE VIRGINIA LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD.
WITH THE SLOW PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE
RIDGES IS FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.
TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.
BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY
MORNING. SOME EARLY MORNING VISIBILITY RESTRICTIONS EXPECTED
ACROSS EASTERN OH IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR.
MID CLOUDS DECK WILL WORK INTO THE AREA MONDAY.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 201802
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
202 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST OVER THE CENTRAL
MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED HEAT SOURCE
EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS EXPECTED FOR THE PERIOD...OUTSIDE OF SOME
PATCHY MVFR RIVER VALLEY FOG DEVELOPING AFTER 09Z. ANY FOG THAT
DEVELOPS WILL BURN OFF BY 13Z FOR A RETURN OF VFR CONDITIONS AREA
WIDE. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 18Z
MONDAY AS A COLD FRONT APPROACHES FROM THE WEST...AND AN UPPER LOW
APPROACHES FROM THE EAST. EXPECT GRADUALLY LOWERING/THICKENING OF
CIGS AFTER 12Z MONDAY AS THESE TWO SYSTEMS APPROACH...ALTHOUGH
CIGS WILL REMAIN ABOVE VFR.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. SHOWERS/STORMS ON MONDAY MAY DEVELOP QUICKER THAN
FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...SL
000
FXUS61 KPBZ 201752
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
152 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRIMARY TWEAK WITH 115 UPDATE WAS TO BUMP UP HIGH TEMPERATURES
ANOTHER DEGREE. HIGH PRESSURE WILL REMAIN IN CONTROL OF WEATHER
THROUGH THIS PERIOD. SOME CUMULUS HAS MANAGED TO DEVELOP SOUTH OF
PITTSBURGH...BUT WITH A 30 DEGREE DEWPOINT DEPRESSION...THIS IS
NOT EXPECTED TO SPREAD MUCH. CLOUD COVER SHOULD GENERALLY COME
WITH HIGH CLOUDS FROM TROPICAL STORM ALBERTO OFF THE SOUTH
CAROLINA COAST. A SLIGHT CHANCE OF SHOWERS WILL BEGIN TO WORK INTO
THE RIDGES LATE TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.
MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH NEAR THE CAROLINAS.
HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE TREND IS
STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING AREA...SO WILL
CONTINUE THE TREND. THE PERIODS IS PROJECTED TO BE WARM WITH ABOVE
AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND SFC DEWPOINTS IN
THE LOW TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY MORNING. SOME
EARLY MORNING VISIBILTY RESTRICTIONS EXPECTED ACROSS EASTERN OH
IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR. MID CLOUDS DECK WILL
WORK INTO THE AREA MONDAY.
.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 201746
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
146 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOSTLY SUNNY SKIES ACROSS MUCH OF THE AREA THIS AFTERNOON. SOME
THIN CIRRUS ACROSS THE WEST CONTINUES TO MOVE NORTHWARD. ADJUSTED
TEMPS ESPECIALLY WITH LAKE BREEZE KICKING IN WITH TEMPS MAXED OUT
AT ERI AND ALONG THE REMAINING LAKESHORE LOCATIONS. RADAR SHOWS
ONLY FAINT LAKE BREEZE RETURN NEAR CLE AS OF 16Z.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE WATCHED.
TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...ABE
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KIELTYKA
MARINE...KOSARIK
000
FXUS61 KILN 201728
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
128 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION TODAY.
LOW PRESSURE WILL TRACK ACROSS THE AREA ON MONDAY AND THEN LINGER
SOUTHEAST OF THE REGION THROUGH MIDWEEK AS HIGH PRESSURE SLOWLY
BUILDS IN FROM THE NORTHWEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
GENERALLY LOWERED THE SKY COVER TODAY AND EXPECT CU TO DEVELOP
OUTSIDE OF WHERE THE DENSER CI IS AT. ONCE CI MIXES OUT THE REST
OF THE AREA WILL SEE SOME SCATTERED FAIR WX CU. TEMPERATURES TODAY
WERE ONLY MODIFIED SLIGHTLY. MORNING UPDATES WERE PRIMARILY
COSMETIC TO BLEND OBSERVED VALUES WITH THE FORECAST VALUES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
TROUGH OVER THE NORTH CENTRAL STATES WILL HEAD EAST AND ENGULF THE
REMNANTS OF THE SOUTHEAST UPPER SYSTEM. THIS WILL RESULT IN VERY
SLOW LONG WAVE PROGRESSION.
INITIAL SHORT WAVE IN THE TROUGH APPROACHING FROM THE WEST WILL
PUSH INTO THE AREA ON MONDAY ALONG WITH A SURFACE LOW. THIS SHOULD
BE SUFFICIENT TO GENERATE SHOWERS AND THUNDERSTORMS PARTICULARLY
IN WESTERN ZONES. EXPECT COVERAGE TO DECREASE AT NIGHT BUT MAKE
SOME SLOW EASTWARD PROGRESS. THERE MAY BE REGENERATION ON TUESDAY
MAINLY IN THE SOUTHEAST COUNTIES AS AN UPPER LOW DEVELOPS WITHIN
THE MEAN TROUGH JUST SOUTHEAST OF THE AREA.
IN GENERAL LEANED TOWARDS WARMER GUIDANCE TEMPERATURES UNTIL
TUESDAY WHEN COOLER NUMBERS SEEMED MORE APPROPRIATE WITH EXTENSIVE
CLOUD COVER AND LOWER HEIGHTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
NEW UPPER LOW THAT DEVELOPS SOUTHEAST OF THE AREA WILL SLOWLY MOVE
EAST EARLY IN THE PERIOD. IT WILL BE IN CLOSE ENOUGH PROXIMITY
THAT SOME SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT OF THE
SOUTHEAST COUNTIES THROUGH WEDNESDAY. THEREAFTER AN UPPER RIDGE
WILL BUILD INTO THE REGION. MODELS ARE SHOWING SOME ENERGY RIDING
OVER THE TOP OF THE RIDGE ALTHOUGH THERE ARE DISCREPANCIES IN HOW
STRONG THIS ENERGY IS AND WHETHER IT CAN TEMPORARILY SUPPRESS THE
RIDGE. HAVE FAVORED A SOLUTION WITH A STRONGER RIDGE. ALTHOUGH
WILL HAVE TO WATCH FOR THE POTENTIAL FOR CONVECTION AS THE SHORT
WAVE RIDES OVER TOP THE RIDGE ON FRIDAY. TEMPERATURES WILL BE
WARMING THROUGH THE PERIOD. AND THERE IS THE POTENTIAL TO SEE SOME
90S BY THE WEEKEND.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
LIGHT SOUTHEAST WINDS WILL PREVAIL AHEAD OF THE NEXT FRONT THAT IS
EXPECTED TO CROSS THE REGION EARLY ON MONDAY. LOOKING AT THE SAME
SYSTEM NOW...THERE IS VERY LITTLE ACTIVITY NOTED AND THE EXPECTED
LARGER SCALE FORCING WITH THE FRONT WILL BE WELL NORTH AND WELL
SOUTHWEST OF THE OHIO VALLEY. I DO NOT SEE THE LARGE THREAT FOR
THUNDERSTORMS ON MONDAY WITH THIS FROPA. IT SHOULD BE MORE
SCATTERED SHOWERS OF A GENERALLY LIGHT NATURE. THE FINER DETAILS
ARE STILL IN QUESTION BUT ALMOST ALL OF THE MODELS ARE HINTING
THAT THIS FROPA WILL HAVE DISJOINTED PRECIPIATION WITH IT AND NOT
A LINE OF SHOWERS THAT HITS EVERYONE IN ITS PATH.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...FRANKS
SHORT TERM...
LONG TERM...
AVIATION...FRANKS
000
FXUS61 KPBZ 201716
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
116 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRIMARY TWEAK WITH 115 UPDATE WAS TO BUMP UP HIGH TEMPERATURES
ANOTHER DEGREE. HIGH PRESSURE WILL REMAIN IN CONTROL OF WEATHER
THROUGH THIS PERIOD. SOME CUMULUS HAS MANAGED TO DEVELOP SOUTH OF
PITTSBURGH...BUT WITH A 30 DEGREE DEWPOINT DEPRESSION...THIS IS
NOT EXPECTED TO SPREAD MUCH. CLOUD COVER SHOULD GENERALLY COME
WITH HIGH CLOUDS FROM TROPICAL STORM ALBERTO OFF THE SOUTH
CAROLINA COAST. A SLIGHT CHANCE OF SHOWERS WILL BEGIN TO WORK INTO
THE RIDGES LATE TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.
MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.
.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 201637
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
1237 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOSTLY SUNNY SKIES ACROSS MUCH OF THE AREA THIS AFTERNOON. SOME
THIN CIRRUS ACROSS THE WEST CONTINUES TO MOVE NORTHWARD. ADJUSTED
TEMPS ESPECIALLY WITH LAKE BREEZE KICKING IN WITH TEMPS MAXED OUT
AT ERI AND ALONG THE REMAINING LAKESHORE LOCATIONS. RADAR SHOWS
ONLY FAINT LAKE BREEZE RETURN NEAR CLE AS OF 16Z.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL CONTINUE TODAY INTO TONIGHT. HIGH CLOUDS WILL
CROSS THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND
KCLE AGAIN THIS AFTERNOON...THEN SHIFT BACK FROM THE SOUTH THIS
EVENING.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...ABE
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KPBZ 201528
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1128 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
WITH 1130AM UPDATE...MAIN CHANGE TO FORECAST WAS TO MODIFY HIGH
TEMPERATURES FOR THIS AFTERNOON. HAVE BUMPED UP HIGHS A COUPLE OF
DEGREES CONSIDERING TEMPS HAVE RISEN QUICKLY THIS MORNING.
PREVIOUS DISCUSSION FOLLOWS.
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.
THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO
MAV GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD
MAKE IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO
WITH A PERSISTENCE TEMPERATURE FORECAST.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.
MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.
.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 201403
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1003 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE... NO SIGNIFICANT CHANGES AT THIS TIME.
PREVIOUS DISCUSSION BELOW...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY L H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...SL/30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
000
FXUS61 KCLE 201341
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
941 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO MAJOR CHANGES NEED THIS MORNING. SATELLITE SHOWING SOME CIRRUS
ACROSS THE WESTERN HALF OF THE AREA THIS MORNING...AND MORE
EXPECTED THIS AFTERNOON WITH LITTLE TO NO IMPACT ON TEMPS. ONLY
TEMP ADJUSTMENT WAS ACROSS INTERIOR NW PA WHERE MID 80S SEEM MORE
REASONABLE ACROSS THE HIGHER ELEVATIONS THERE. PREVIOUS DISCUSSION
BELOW.
CIRRUS CONTINUES TO STREAM INTO THE REGION THIS MORNING. THE THIN
HIGH CLOUDS SHOULD HAVE LITTLE EFFECT ON SOLAR INSOLATION TODAY
AND STILL LOOKING AT HIGHS IN THE MIDDLE TO UPPER 80S ACROSS THE
FORECAST AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE TODAY INTO TONIGHT. HIGH CLOUDS WILL
CROSS THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND
KCLE AGAIN THIS AFTERNOON...THEN SHIFT BACK FROM THE SOUTH THIS
EVENING.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...ABE/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KPBZ 201210
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
810 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
WITH 8AM UPDATE...ONLY MINOR TWEAKS WERE MADE TO HOURLY
SKY/TEMPERATURE TRENDS. PREVIOUS DISCUSSION FOLLOWS.
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.
THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO
MAV GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD
MAKE IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO
WITH A PERSISTENCE TEMPERATURE FORECAST.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.
MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.
.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 201138
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
738 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CIRRUS CONTINUES TO STREAM INTO THE REGION THIS MORNING. THE THIN
HIGH CLOUDS SHOULD HAVE LITTLE EFFECT ON SOLAR INSOLATION TODAY
AND STILL LOOKING AT HIGHS IN THE MIDDLE TO UPPER 80S ACROSS THE
FORECAST AREA.
NO CHANGES NEEDED WITH THIS PACKAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE TODAY INTO TONIGHT. HIGH CLOUDS WILL
CROSS THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND
KCLE AGAIN THIS AFTERNOON...THEN SHIFT BACK FROM THE SOUTH THIS
EVENING.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KILN 201044
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
644 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION TODAY.
LOW PRESSURE WILL TRACK ACROSS THE AREA ON MONDAY AND THEN LINGER
SOUTHEAST OF THE REGION THROUGH MIDWEEK AS HIGH PRESSURE SLOWLY
BUILDS IN FROM THE NORTHWEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE CENTERED EAST OF THE REGION WILL EXERT ITS INFLUENCE
ACROSS THE FORECAST AREA FOR ONE MORE DAY. A WEAK SHORT WAVE
ROTATING AROUND UPPER SYSTEM ALONG THE SOUTHEAST COAST HAS SPREAD
CIRRUS ACROSS THE REGION. DIFFICULT TO TELL FROM IR SATELLITE HOW
THICK THIS DECK IS. BUT WOULD EXPECT AT LEAST SOME SUNSHINE TO
WORK THROUGH DURING THE DAY. CIRRUS MAY HAVE A SLIGHT EFFECT ON
TEMPERATURES. WENT PRETTY CLOSE TO PERSISTENCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
TROUGH OVER THE NORTH CENTRAL STATES WILL HEAD EAST AND ENGULF THE
REMNANTS OF THE SOUTHEAST UPPER SYSTEM. THIS WILL RESULT IN VERY
SLOW LONG WAVE PROGRESSION.
INITIAL SHORT WAVE IN THE TROUGH APPROACHING FROM THE WEST WILL
PUSH INTO THE AREA ON MONDAY ALONG WITH A SURFACE LOW. THIS SHOULD
BE SUFFICIENT TO GENERATE SHOWERS AND THUNDERSTORMS PARTICULARLY
IN WESTERN ZONES. EXPECT COVERAGE TO DECREASE AT NIGHT BUT MAKE
SOME SLOW EASTWARD PROGRESS. THERE MAY BE REGENERATION ON TUESDAY
MAINLY IN THE SOUTHEAST COUNTIES AS AN UPPER LOW DEVELOPS WITHIN
THE MEAN TROUGH JUST SOUTHEAST OF THE AREA.
IN GENERAL LEANED TOWARDS WARMER GUIDANCE TEMPERATURES UNTIL
TUESDAY WHEN COOLER NUMBERS SEEMED MORE APPROPRIATE WITH EXTENSIVE
CLOUD COVER AND LOWER HEIGHTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
NEW UPPER LOW THAT DEVELOPS SOUTHEAST OF THE AREA WILL SLOWLY MOVE
EAST EARLY IN THE PERIOD. IT WILL BE IN CLOSE ENOUGH PROXIMITY
THAT SOME SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT OF THE
SOUTHEAST COUNTIES THROUGH WEDNESDAY. THEREAFTER AN UPPER RIDGE
WILL BUILD INTO THE REGION. MODELS ARE SHOWING SOME ENERGY RIDING
OVER THE TOP OF THE RIDGE ALTHOUGH THERE ARE DISCREPANCIES IN HOW
STRONG THIS ENERGY IS AND WHETHER IT CAN TEMPORARILY SUPPRESS THE
RIDGE. HAVE FAVORED A SOLUTION WITH A STRONGER RIDGE. ALTHOUGH
WILL HAVE TO WATCH FOR THE POTENTIAL FOR CONVECTION AS THE SHORT
WAVE RIDES OVER TOP THE RIDGE ON FRIDAY. TEMPERATURES WILL BE
WARMING THROUGH THE PERIOD. AND THERE IS THE POTENTIAL TO SEE SOME
90S BY THE WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FOG HAS DEVELOPED AT KLUK THIS MORNING HOWEVER EXPECT VFR
CONDITIONS TO RETURN BY 13Z. OTHER AREA TAF SITES WILL BE VFR
THROUGH THE TAF PERIOD. HIGH CLOUDS HAVE OVERSPREAD THE AREA AND
WILL CONTINUE TO DO SO THROUGH THE TAF PERIOD. SOME CU WILL DEVELOP
BY THE AFTERNOON HOURS AS WELL ACROSS MOST OF THE TAF SITES. A
COLD FRONT WILL BEGIN TO APPROACH THE AREA SUNDAY NIGHT. ONLY
INSERTED PRECIPITATION AT KCVG DUE TO LONGER TAF TIME FRAME.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
000
FXUS61 KCLE 201028
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
628 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CIRRUS CONTINUES TO STREAM INTO THE REGION THIS MORNING. THE THIN
HIGH CLOUDS SHOULD HAVE LITTLE EFFECT ON SOLAR INSOLATION TODAY
AND STILL LOOKING AT HIGHS IN THE MIDDLE TO UPPER 80S ACROSS THE
FORECAST AREA.
NO CHANGES NEEDED WITH THIS PACKAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE. PATCHES OF HIGH CLOUDS WILL CROSS
THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND KCLE
AGAIN THIS AFTERNOON.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON INTO WEDNESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KRLX 201023
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
623 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
600AM UPDATE...
NO CHANGES AT THIS TIME.
PREVIOUS DISCUSSION BELOW...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY M L L H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY M H H H H H H H H H H H
PKB CONSISTENCY M H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
000
FXUS61 KPBZ 200924
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
524 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.
THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO MAV
GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD MAKE
IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO WITH
A PERSISTENCE TEMPERATURE FORECAST.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT THE AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.
MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.
.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY WHILE MOISTURE INCREASES FROM THE EAST AS LOW
PRESSURE MOVES UP THE EASTERN SEABOARD. RESTRICTIONS POSSIBLE
THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT EAST OF THE AREA
BY WEDNESDAY NIGHT WITH GENERAL VFR THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KILN 200836
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
436 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION TODAY.
LOW PRESSURE WILL TRACK ACROSS THE AREA ON MONDAY AND THEN LINGER
SOUTHEAST OF THE REGION THROUGH MIDWEEK AS HIGH PRESSURE SLOWLY
BUILDS IN FROM THE NORTHWEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE CENTERED EAST OF THE REGION WILL EXERT ITS INFLUENCE
ACROSS THE FORECAST AREA FOR ONE MORE DAY. A WEAK SHORT WAVE
ROTATING AROUND UPPER SYSTEM ALONG THE SOUTHEAST COAST HAS SPREAD
CIRRUS ACROSS THE REGION. DIFFICULT TO TELL FROM IR SATELLITE HOW
THICK THIS DECK IS. BUT WOULD EXPECT AT LEAST SOME SUNSHINE TO
WORK THROUGH DURING THE DAY. CIRRUS MAY HAVE A SLIGHT EFFECT ON
TEMPERATURES. WENT PRETTY CLOSE TO PERSISTENCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
TROUGH OVER THE NORTH CENTRAL STATES WILL HEAD EAST AND ENGULF THE
REMNANTS OF THE SOUTHEAST UPPER SYSTEM. THIS WILL RESULT IN VERY
SLOW LONG WAVE PROGRESSION.
INITIAL SHORT WAVE IN THE TROUGH APPROACHING FROM THE WEST WILL
PUSH INTO THE AREA ON MONDAY ALONG WITH A SURFACE LOW. THIS SHOULD
BE SUFFICIENT TO GENERATE SHOWERS AND THUNDERSTORMS PARTICULARLY
IN WESTERN ZONES. EXPECT COVERAGE TO DECREASE AT NIGHT BUT MAKE
SOME SLOW EASTWARD PROGRESS. THERE MAY BE REGENERATION ON TUESDAY
MAINLY IN THE SOUTHEAST COUNTIES AS AN UPPER LOW DEVELOPS WITHIN
THE MEAN TROUGH JUST SOUTHEAST OF THE AREA.
IN GENERAL LEANED TOWARDS WARMER GUIDANCE TEMPERATURES UNTIL
TUESDAY WHEN COOLER NUMBERS SEEMED MORE APPROPRIATE WITH EXTENSIVE
CLOUD COVER AND LOWER HEIGHTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
NEW UPPER LOW THAT DEVELOPS SOUTHEAST OF THE AREA WILL SLOWLY MOVE
EAST EARLY IN THE PERIOD. IT WILL BE IN CLOSE ENOUGH PROXIMITY
THAT SOME SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT OF THE
SOUTHEAST COUNTIES THROUGH WEDNESDAY. THEREAFTER AN UPPER RIDGE
WILL BUILD INTO THE REGION. MODELS ARE SHOWING SOME ENERGY RIDING
OVER THE TOP OF THE RIDGE ALTHOUGH THERE ARE DISCREPANCIES IN HOW
STRONG THIS ENERGY IS AND WHETHER IT CAN TEMPORARILY SUPPRESS THE
RIDGE. HAVE FAVORED A SOLUTION WITH A STRONGER RIDGE. ALTHOUGH
WILL HAVE TO WATCH FOR THE POTENTIAL FOR CONVECTION AS THE SHORT
WAVE RIDES OVER TOP THE RIDGE ON FRIDAY. TEMPERATURES WILL BE
WARMING THROUGH THE PERIOD. AND THERE IS THE POTENTIAL TO SEE SOME
90S BY THE WEEKEND.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL CONTINUE TO KEEP DRY CONDITIONS ACROSS THE TAF
SITES. WITH LIGHT SE FLOW ACROSS THE AREA FOG WILL DEVELOP AT
KLUK FOR THE OVERNIGHT HOURS. VFR CONDITIONS CAN BE EXPECTED AT
THE OTHER AREA TAF SITES THROUGH THE TAF PERIOD. HIGH CLOUDS WILL
BE PRESENT ACROSS THE TAF SITES FOR MOST OF THE TAF TIME FRAME
WITH A FEW CU ALSO PRESENT FOR MAINLY THE AFTERNOON HOURS ON
SUNDAY ACROSS THE WESTERN TAF SITES KCVG...KLUK...AND KDAY. WINDS
WILL BE LESS THAN 10 KNOTS.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
000
FXUS61 KCLE 200744
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
344 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE HIGH PRESSURE WILL CONTINUE TO BE THE DOMINANT WEATHER FEATURE
ACROSS THE FORECAST AREA TODAY. THE TROPICAL SYSTEM OFF THE COAST OF
SOUTH CAROLINA WILL STREAM SOME HIGH LEVEL CIRRUS CLOUDS NORTH INTO
THE FORECAST AREA TODAY AS WELL. CIRRUS SHOULD REMAIN THIN ENOUGH TO
PREVENT ANY REDUCTION IN SUNSHINE.
ANOTHER WARM DAY ON TAP AS STRONGER WARM AIR ADVECTION TAKES PLACE
WITH ABUNDANT SUNSHINE. TEMPERATURES WERE ABOUT 4 DEGREES WARMER
THAN FORECAST IN THE WEST YESTERDAY. I ADVECTED THE WARMER AIR MASS
THAT WAS UPSTREAM FURTHER EAST INTO THE REST OF THE FORECAST AREA.
LOOKING AT HIGH TEMPERATURES IN THE MIDDLE TO UPPER 80S TODAY OVER
THE ENTIRE FORECAST AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.
MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.
THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.
DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE. PATCHES OF HIGH CLOUDS WILL CROSS
THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND KCLE
AGAIN THIS AFTERNOON.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON INTO WEDNESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.
AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.
A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KRLX 200742
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
333 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
OVERALL VFR CONDITIONS THROUGH THE
PERIOD...WITH THE EXCEPTION OF SOME MVFR FOG AFTER 06Z IN TYPICAL
RIVER VALLEY LOCATIONS...IE KCRW...KHTS...KPKB. HAVE SOME IFR
TYGART VALLEY BY 10Z TO INCLUDE KEKN.
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 05/20/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H M H H H H H H
HTS CONSISTENCY H M M M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H M L M H H H H H H
PKB CONSISTENCY H M M M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
000
FXUS61 KCLE 200549
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
149 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH TOMORROW AND THEN MOVE OFF THE EAST COAST ON MONDAY. A
COLD FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM
THE WEST WHILE LOW PRESSURE MOVES NORTH ALONG THE MID ATLANTIC
COAST MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE
EAST ON TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
GOING FORECAST REMAINS ON TRACK. CIRRUS CONTINUES TO THIN AS IT
SPREADS NORTH ACROSS EASTERN OHIO/WESTERN PA AND SHOULD NOT HAVE A
LIMITING EFFECT ON MINS FOR TONIGHT.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE AREA TONIGHT WILL ALLOW FOR
MAINLY CLEAR SKIES AND QUIET CONDITIONS. SOME CIRRUS CLOUDS MOVING
NORTHWARD INTO EASTERN AREAS...BUT NOT ENOUGH COVERAGE IN GRIDS TO
MENTION PARTLY CLOUDY. MAINLY MOSTLY CLEAR SKIES TONIGHT. USED A
BLEND OF MET AND MAV TEMPS...WITH LOWER 50S IN THE GOOD RADIATING
SPOTS. WOULD NOT BE SURPRISED TO SEE UPPER 40S ACROSS THE INTERIOR
OF NW PA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAIN ACROSS THE AREA ON SUNDAY WITH TEMPS SIMILAR
OR A BIT WARMER...WITH A LAKE BREEZE LIKELY IN THE AFTERNOON.
THERE MAY BE SOME CIRRUS CLOUDS ACROSS THE EAST AGAIN BUT NOT MUCH
IMPACT ON THE MOSTLY SUNNY SKIES. LOWS WARMER SUNDAY NIGHT AS A
COLD FRONT APPROACHES FROM THE WEST.
MODELS SHOWING A COLD FRONT APPROACHING THE AREA MONDAY. FOR NOW
WENT WITH MAINLY DRY CONDITIONS IN THE MORNING WITH INCREASING
POPS ACROSS THE WEST IN THE AFTERNOON. MEANWHILE...MOISTURE
SPREADING WESTWARD FROM LOW PRESSURE ALONG THE EAST COAST. WHILE
THERE IS STILL SOME DISCREPANCIES AS TO HOW FAR PRECIP WILL GET
ACROSS THE APPALACHIANS THERE WILL AT LEAST BE INCREASING CLOUDS.
MENTION LOW CHC POPS ACROSS THE FAR EAST INCLUDING NW PA IN THE
AFTERNOON...WITH CHC POPS ALSO ACROSS THE WEST WITH THE COLD FRONT
APPROACHING. CENTRAL LOCATIONS FROM CLE-MFD ONLY HAVE SLGT UNTIL
MONDAY NIGHT.
BETWEEN THE FRONT AND ANY POSSIBLE SHOWERS FROM MOISTURE BY THE
EAST COAST LOW LOOKS LIKE THERE WILL BE AT LEAST A CHANCE FOR
SHRA/TS MONDAY NIGHT ACROSS THE ENTIRE AREA. GIVEN INCREASING
DEWPOINTS ACROSS THE AREA KEEP LOWS AROUND 60 FOR MUCH OF THE
AREA.
MODELS SHOWING AN UPPER TROUGH OVER THE OHIO VALLEY SOUTH OF THE
AREA THROUGH TUESDAY...SO GIVEN SOME REMAINING INSTABILITY ACROSS
THE AREA CHC POPS FOR SHRA/THUNDERSTORMS CONTINUE. GFS A BIT
QUICKER THAN 12Z ECMWF IN BRINGING IN HIGH PRESSURE THROUGH
TUESDAY NIGHT. ALLOWED WESTERN AREAS TO DRY OUT TUESDAY NIGHT
WHILE LOWERING POPS TO SLGT CHC/LOW CHC ACROSS THE FAR EAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS NOT IN COMPLETE AGREEMENT. THE GFS HAS AN UPPER RIDGE
ACROSS THE REGION WEDNESDAY WHILE THE 12Z ECMWF HAS AN UPPER LOW
OVER THE TENNESSEE VALLEY THAT WILL VERY SLOWLY MOVE SOUTHEAST
THROUGH THURSDAY NIGHT. IF THE ECMWF IS CORRECT THIS COULD MEAN A
THREAT OF PRECIPITATION WILL HANG ON OVER NORTHEAST OHIO AND
NORTHWEST PA INTO THURSDAY NIGHT. BECAUSE OF THE UNCERTAINTY KEPT
LOW CHANCE POPS INTO WEDNESDAY FOR THE EASTERN PORTION OF THE
FORECAST AREA AND THEN DRY AFTER THAT. THIS WILL HAVE TO BE
MONITORED.
BY THE END OF THE WEEK A RIDGE ALOFT WILL BE OVER THE AREA WITH
PLENTY OF WARM TEMPERATURES AND HIGHS NEAR 90. OTHERWISE WENT CLOSE
TO HPC FOR TEMPERATURES.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE. PATCHES OF HIGH CLOUDS WILL CROSS
THE AREA. LAKE BREEZE WIND SHIFTS WILL OCCUR AT KERI AND KCLE
AGAIN THIS AFTERNOON.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON INTO WEDNESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WORK WEEK...HOWEVER...FORECASTS WILL HAVE TO BE
MONITORED BECAUSE OF MODEL UNCERTAINTY.
THE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY WEAKEN ON
SUNDAY. A WEAK COLD FRONT WILL MOVE ACROSS THE LAKE MONDAY INTO
MONDAY NIGHT. THE WINDS WILL BE ONSHORE BEHIND THE FRONT BUT IT
LOOKS LIKE THEY WILL BE WEAK ENOUGH THAT A SMALL CRAFT ADVISORY MAY
NOT BE NEEDED. HIGH PRESSURE BUILDS BACK IN BY LATE TUESDAY AND THEN
THE RIDGE MOVES EAST WEDNESDAY AND THE AREA GETS INTO A SOUTHWEST OR
SOUTH FLOW. THE NEXT FRONTAL SYSTEM MOVES TOWARD THE LAKE FOR THE
EARLY PART OF NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/KEC
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KOSARIK
MARINE...KIELTYKA
000
FXUS61 KPBZ 200541
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
141 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TODAY/...
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. FOR THE REMAINDER OF THE
OVERNIGHT...NEAR CALM WINDS AND MOSTLY CLEAR SKIES WILL ALLOW FOR
TEMPERATURES TO DROP GENERALLY INTO THE 50S. HOWEVER...SOME CIRRUS
ASSOCIATED WITH TS ALBERTO WILL SPREAD OVERHEAD MAKING FOR A LESS
THAN OPTIMAL RADIATIONAL COOLING NIGHT. THIS SHOULD ALSO KEEP THE
TEMP/DEWPOINT SPREAD FROM REACHING SATURATION AT THE SURFACE
THOUGH SOME PATCHY VALLEY FOG COULD NOT BE RULED OUT.
WHAT IS NOW ESSENTIALLY A FOLD-OVER RIDGE WILL RIDE NORTH OVER THE
UPPER LEVEL CUTOFF LOW OF BOTH ALBERTO AND A LOW SITUATED TO ITS
NORTHEAST...BEST DEPICTED ON IR SATELLITE. A MORE SOUTHERLY WIND
COMPONENT AND GENERALLY CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES
TO REBOUND TO WELL ABOVE NORMAL ONCE AGAIN. HEDGED CLOSEST TO MAV
GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD MAKE
IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO WITH
PERSISTENCE TEMPERATURE FORECAST.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
GFS/ECMWF INDICATE THE RIDGE AXIS BECOMING PINCHED OFF SUNDAY NIGHT
INTO MONDAY AS THE UPPER LOW MOVES INTO VIRGINIA AND A TROUGH MOVES
INTO THE UPPER MIDWEST. THE CLOSED LOW WILL SERVE TO DRAW MOISTURE
INTO THE AREA FROM THE ATLANTIC. WITH THIS IN MIND, THE CHANCE OF
SHOWERS BEGINS SOUTHEAST OF PITTSBURGH ON MONDAY MORNING. IN
ASSOCIATION WITH THE TROUGH, A FRONTAL BOUNDARY WILL CROSS THE OHIO
VALLEY ON MONDAY AFTERNOON. INCREASING MOISTURE AND INSTABILITY
AHEAD OF THIS FEATURE WILL LEAD TO THE CHANCE OF SHOWERS AND
THUNDERSTORMS MONDAY AFTERNOON THROUGH THE EVENING. INCREASED
CLOUD COVERAGE AND COOLER TEMPS ALOFT ASSOCIATED WITH THE LOW
APPROACHING FROM THE SOUTHEAST WILL ALLOW FOR A SLIGHT COOLER DAY
ON MONDAY, WITH HIGH TEMPS AT 5 TO 10 DEGREES ABOVE NORMAL,
RANGING FROM THE LOWER 80S ACROSS EASTERN OHIO TO NEAR 70 ACROSS
THE EASTERN RIDGES.
SOME MODEL UNCERTAINTY ENTERS THE FORECAST IN REGARDS TO THE TROUGH
MOVING INTO THE AREA FROM THE UPPER MIDWEST. ECMWF/NAM SOLUTIONS
MERGE THE UPPER LOW TO THE SOUTHEAST WITH THIS FEATURE INTO A MORE
AMPLIFIED TROUGH ACROSS THE AREA. MEANWHILE, THE GFS MOVES THE UPPER
LOW UP THE EAST COAST AND BRINGS A WEAKER TROUGH ACROSS THE AREA. WITH
THIS UNCERTAINTY IN MIND AND THE SLOW PASSAGE OF A FRONTAL
BOUNDARY, FORECAST IS A BLEND OF THE SOLUTIONS, CONTINUING A
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY.
WITH INCREASED CLOUD COVERAGE WITH SHOWERS AND THUNDERSTORMS,
HIGHS ON TUESDAY WILL BE SLIGHTLY COOLER IN COMPARISON TO THE
WEEKEND AND MONDAY, ALTHOUGH STILL AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.
.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY WHILE MOISTURE INCREASES FROM THE EAST AS LOW
PRESSURE MOVES UP THE EASTERN SEABOARD. RESTRICTIONS POSSIBLE
THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT EAST OF THE AREA
BY WEDNESDAY NIGHT WITH GENERAL VFR THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 200525
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
125 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY LOW PRESSURE CLOSE BY TO THE EAST LATE
TONIGHT AND MONDAY GETS KICKED OUT BY SYSTEM COMING FROM THE WEST
MONDAY NIGHT. THE NEW SYSTEM CROSSES TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SRC. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AREA IS ON WESTERN FRINGES OF MID ATLANTIC STACKED LOW PRESSURE
SYSTEM SUN NT AND MON...BEFORE THAT SYSTEM IS KICKED E BY A NEW
UPSTREAM NORTHERN STREAM S/W TROUGH. SOME OF THE ENERGY FROM THE
NORTHERN STREAM TROUGH GETS FED INTO THE SOUTHERN STREAM...THUS
HELPING TO KICK THE MID ATLANTIC LOW OUT. MAINTAINED THE IDEA OF
CHANCE THUNDERSTORMS MAINLY IN THE MOUNTAINS. A SPOKE OF ENERGY
ROTATING AROUND THE N SIDE OF THE MID ATLANTIC LOW DAMPENS THE
DIURNAL CYCLE AS IT MOVES INTO THE NORTHERN MOUNTAINS MON MORNING.
THE NEW S/W APPROACHES LATE MON AND MOVES ACROSS MON NT THROUGH
TUE. THE THUNDERSTORM CHANCE SHOULD INCREASE FROM THE W LATE MON
GIVEN SFC LOW PRESSURE AND ASSOCIATED CONVERGENCE THERE...THE
APPROACH OF THE UPPER LEVEL SYSTEM...AND THE INSTABILITY AXIS
LOCATED ALONG THE SFC TROUGH. NAM12 SUGGESTS CAPE TO 2500 J / KG
AND LIX TO -6 AND ABOUT A BUCK AND A THIRD PW. FLOW IS ON THE ORDER
OF TEN KNOTS SO SLOW MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW
VALUES WIND UP HIGHER THAN THAT.
CARRIED HIGH CHANCE SHOWERS AND THUNDERSTORMS WELL INTO TUE NT...AS
IT IS HARD TO DETERMINE MOVEMENT OF CLUSTERS WITHIN THE SLOW MOVING
PARENT SYSTEM. MODEL DIFFERENCES REMAIN AS TO WHETHER THE NEW
SYSTEM SIMPLY TAKES OVER AS A NEW MID ATLANTIC UPPER LEVEL LOW.
THIS FACTORS INTO HOW QUICKLY PRECIPITATION ENDS FROM THE W TUE NT.
CONTINUE WITH A MIDDLE GROUND TO SLOW STANCE HERE...WITH THE GFS
MOST PROGRESSIVE.
BLENDED IN THE MET FOR TEMPERATURES EARLY ON AND THEN THE BIAS
CORRECTED MAV FOR HIGHS TUE...TO BETTER REFLECT TEMPERATURE TRENDS
IN RELATION TO THE UPPER LEVEL SYSTEM THAT ARRIVES FROM THE W. THE
COOLEST PERIOD LOOKS TO BE TUE THROUGH TUE NT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLNS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
OVERALL VFR CONDITIONS THROUGH THE
PERIOD...WITH THE EXCEPTION OF SOME MVFR FOG AFTER 06Z IN TYPICAL
RIVER VALLEY LOCATIONS...IE KCRW...KHTS...KPKB. HAVE SOME IFR
TYGART VALLEY BY 10Z TO INCLUDE KEKN.
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 05/20/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H M H H H H H H
HTS CONSISTENCY H M M M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H M L M H H H H H H
PKB CONSISTENCY H M M M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...30
000
FXUS61 KILN 200521
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
121 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE WEEKEND. A SLOW
MOVING FRONT WILL MOVE EAST INTO THE OHIO VALLEY ON
MONDAY...PROVIDING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY. DRY WEATHER AND WARMING TEMPERATURES WILL BE IN PLACE FOR
THE REST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPPER LEVEL CLOUDS FROM TS ALBERTO ARE WORKING W ACROSS THE
APPALACHIANS. LATEST SATELLITE LOOP IS SHOWING THAT THEY WILL HOLD
TOGETHER AND WILL BRING PC SKIES TO PORTIONS OF THE REGION
OVERNIGHT.
LEFT LOW TEMPERATURE FORECAST AS IT FOR NOW...WAS THE DIURNAL
TRACE WAS CLOSE TO THE OBS...BUT THE CI COULD CAUSE THEM TO STAY A
LITTLE WARMER. WILL KEEP AN EYE ON THIS FOR THE NEXT UPDATE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS WIND FLOW TURNS MORE SOUTHERLY ON SUNDAY...MOISTURE WILL
CONTINUE TO INCREASE SLIGHTLY OVER THE REGION. WITH LESS CAPPING
AND HIGHER DEWPOINTS...SOME INSTABILITY WILL BE
PRESENT...ESPECIALLY IN THE SOUTHWEST. HOWEVER...HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE OVERALL PATTERN...WITH NO SIGNS OF
ANY TRIGGER FOR CONVECTION. THIS MAY BE A SITUATION WHERE A VERY
ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE DURING THE DIURNAL
HEATING CYCLE...AND MAINLY IN THE WEST AND SOUTHWEST PARTS OF THE
CWA. WOULD BEST CATEGORIZE THIS AS A 10-PERCENT POP FOR NOW.
AS A POTENTIAL TROPICAL SYSTEM MOVES NEAR THE COAST...A SLOW
MOVING COLD FRONT ON A SSW-TO-NNE ORIENTATION WILL MOVE INTO THE
OHIO VALLEY. WHILE THIS MAY PRESENT SOME FORECAST DIFFICULTY AS
THE FEATURES INTERACT OVER THE APPALACHIANS...AT THIS TIME THERE
IS HIGH CONFIDENCE THAT THE PROGRESS OF THE FRONT WILL BE LARGELY
UNIMPEDED (THOUGH SLOW) FOR THE ILN FORECAST AREA.
INSTABILITY WILL BE PRESENT AHEAD OF THE FRONT AND WEAK SURFACE
LOW...GENERALLY AROUND 1000 J/KG OF MLCAPE PER GFS AND NAM
DEPICTIONS. THE SLOW MOTION OF THE FRONT AND WEAK WIND FIELDS SEEM
TO PRECLUDE SEVERE WEATHER THREATS...THOUGH THE SLOW MOTION MAY
SUPPORT SOME LOCALLY HEAVY RAINFALL.
MIN TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE
OF GUIDANCE...ESPECIALLY SUNDAY NIGHT AND MONDAY NIGHT. THE RAW NAM
TEMPERATURES CAPTURE THE IMPACTS OF THE FRONTAL SYSTEM AND THE
MOIST AIR MASS ASSOCIATED WITH IT. DEPENDING ON THE RAINFALL
PATTERNS...HIGHS ON MONDAY IN THE WESTERN HALF OF THE CWA MAY COME
EARLIER IN THE DAY THAN NORMAL. THERE IS GOOD AGREEMENT IN THE
MODELS ON MONDAY BEING AROUND 5 DEGREES COOLER THAN
SUNDAY IN THE WEST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
WILL SIDE WITH AN HPC SOLUTION FOR THE EXTENDED FORECAST. THIS
SOLUTION TAKES A BLEND OF THE GFS AND ECMWF IN REGARDS TO UPR LVL
TROUGH POSITION/MOVEMENT FOR THE TUESDAY THROUGH THURSDAY TIME FRAME.
FORECAST WILL ALLOW UPR LVL TROUGH TO GRADUALLY MOVE OFF TO THE EAST
AND CLOSE OFF. CONFIDENCE IS NOT THE HIGHEST WITH THIS SOLUTION AS
MODELS TYPICALLY STRUGGLE WITH HOW UPR TROUGHS CLOSE OFF AND
PROGRESS THEREAFTER. SO IT WILL BEHOOVE ONE TO MONITOR LATER
FORECASTS. MODELS SEEM TO AGREE THAT BY WEEKS END AN UPR LVL RIDGE
WILL BUILD ACRS THE OHIO VALLEY. AS FOR TEMPERATURES...THEY WILL
START OFF NEAR NORMAL TUESDAY AND WEDNESDAY...THEN GRADUALLY WARM TO
ABOVE NORMAL READINGS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL CONTINUE TO KEEP DRY CONDITIONS ACROSS THE TAF
SITES. WITH LIGHT SE FLOW ACROSS THE AREA FOG WILL DEVELOP AT
KLUK FOR THE OVERNIGHT HOURS. VFR CONDITIONS CAN BE EXPECTED AT
THE OTHER AREA TAF SITES THROUGH THE TAF PERIOD. HIGH CLOUDS WILL
BE PRESENT ACROSS THE TAF SITES FOR MOST OF THE TAF TIME FRAME
WITH A FEW CU ALSO PRESENT FOR MAINLY THE AFTERNOON HOURS ON
SUNDAY ACROSS THE WESTERN TAF SITES KCVG...KLUK...AND KDAY. WINDS
WILL BE LESS THAN 10 KNOTS.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...NOVAK
000
FXUS61 KILN 200241
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1041 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE WEEKEND. A SLOW
MOVING FRONT WILL MOVE EAST INTO THE OHIO VALLEY ON
MONDAY...PROVIDING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY. DRY WEATHER AND WARMING TEMPERATURES WILL BE IN PLACE FOR
THE REST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
UPPER LEVEL CLOUDS FROM TS ALBERTO ARE WORKING W ACROSS THE
APPALACHIANS. LATEST SATELLITE LOOP IS SHOWING THAT THEY WILL HOLD
TOGETHER AND WILL BRING PC SKIES TO PORTIONS OF THE REGION
OVERNIGHT.
LEFT LOW TEMPERATURE FORECAST AS IT FOR NOW...WAS THE DIURNAL
TRACE WAS CLOSE TO THE OBS...BUT THE CI COULD CAUSE THEM TO STAY A
LITTLE WARMER. WILL KEEP AN EYE ON THIS FOR THE NEXT UPDATE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS WIND FLOW TURNS MORE SOUTHERLY ON SUNDAY...MOISTURE WILL
CONTINUE TO INCREASE SLIGHTLY OVER THE REGION. WITH LESS CAPPING
AND HIGHER DEWPOINTS...SOME INSTABILITY WILL BE
PRESENT...ESPECIALLY IN THE SOUTHWEST. HOWEVER...HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE OVERALL PATTERN...WITH NO SIGNS OF
ANY TRIGGER FOR CONVECTION. THIS MAY BE A SITUATION WHERE A VERY
ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE DURING THE DIURNAL
HEATING CYCLE...AND MAINLY IN THE WEST AND SOUTHWEST PARTS OF THE
CWA. WOULD BEST CATEGORIZE THIS AS A 10-PERCENT POP FOR NOW.
AS A POTENTIAL TROPICAL SYSTEM MOVES NEAR THE COAST...A SLOW
MOVING COLD FRONT ON A SSW-TO-NNE ORIENTATION WILL MOVE INTO THE
OHIO VALLEY. WHILE THIS MAY PRESENT SOME FORECAST DIFFICULTY AS
THE FEATURES INTERACT OVER THE APPALACHIANS...AT THIS TIME THERE
IS HIGH CONFIDENCE THAT THE PROGRESS OF THE FRONT WILL BE LARGELY
UNIMPEDED (THOUGH SLOW) FOR THE ILN FORECAST AREA.
INSTABILITY WILL BE PRESENT AHEAD OF THE FRONT AND WEAK SURFACE
LOW...GENERALLY AROUND 1000 J/KG OF MLCAPE PER GFS AND NAM
DEPICTIONS. THE SLOW MOTION OF THE FRONT AND WEAK WIND FIELDS SEEM
TO PRECLUDE SEVERE WEATHER THREATS...THOUGH THE SLOW MOTION MAY
SUPPORT SOME LOCALLY HEAVY RAINFALL.
MIN TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE
OF GUIDANCE...ESPECIALLY SUNDAY NIGHT AND MONDAY NIGHT. THE RAW NAM
TEMPERATURES CAPTURE THE IMPACTS OF THE FRONTAL SYSTEM AND THE
MOIST AIR MASS ASSOCIATED WITH IT. DEPENDING ON THE RAINFALL
PATTERNS...HIGHS ON MONDAY IN THE WESTERN HALF OF THE CWA MAY COME
EARLIER IN THE DAY THAN NORMAL. THERE IS GOOD AGREEMENT IN THE
MODELS ON MONDAY BEING AROUND 5 DEGREES COOLER THAN
SUNDAY IN THE WEST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
WILL SIDE WITH AN HPC SOLUTION FOR THE EXTENDED FORECAST. THIS
SOLUTION TAKES A BLEND OF THE GFS AND ECMWF IN REGARDS TO UPR LVL
TROUGH POSITION/MOVEMENT FOR THE TUESDAY THROUGH THURSDAY TIME FRAME.
FORECAST WILL ALLOW UPR LVL TROUGH TO GRADUALLY MOVE OFF TO THE EAST
AND CLOSE OFF. CONFIDENCE IS NOT THE HIGHEST WITH THIS SOLUTION AS
MODELS TYPICALLY STRUGGLE WITH HOW UPR TROUGHS CLOSE OFF AND
PROGRESS THEREAFTER. SO IT WILL BEHOOVE ONE TO MONITOR LATER
FORECASTS. MODELS SEEM TO AGREE THAT BY WEEKS END AN UPR LVL RIDGE
WILL BUILD ACRS THE OHIO VALLEY. AS FOR TEMPERATURES...THEY WILL
START OFF NEAR NORMAL TUESDAY AND WEDNESDAY...THEN GRADUALLY WARM TO
ABOVE NORMAL READINGS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AFTN CU HAVE DISSIPATED OVER THE SRN TAFS...BUT SOME CI FROM
TROPICAL STORM ALBERTO IS WORKING W INTO THE TAFS. NAM AND GFS ARE
SUGGESTING THAT THE CI COULD GO BROKEN AT TIMES OVERNIGHT AT THE
ERN TAFS.
OTHER THAN THAT...THE TAFS WILL REMAIN SANDWICHED BETWEEN A
DIGGING H5 TROF TO THE W AND ALBERTO TO THE E. CURU IS INDICATING
THAT THE BEST CU WILL POP ACROSS INDIANA TOMORROW...LEAVING THE
WRN TAFS ON THE FRINGE...WITH LITTLE CU IN THE E.
WEAK SE FLOW OVERNIGHT....SO ALLOW IFR FOG AGAIN AT LUK BETWEEN
09Z-12Z.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
000
FXUS61 KRLX 200223
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1023 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE INTO SUNDAY. LOW PRESSURE CLOSE BY TO THE EAST LATE
SUNDAY THROUGH MONDAY GETS KICKED OUT BY SYSTEM COMING FROM THE WEST
MONDAY NIGHT. THE NEW SYSTEM CROSSES TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH SUNDAY/...
1020 PM UPDATE...ONE STRAY SHOWER POPPED UP IN FAYETTE/RALEIGH
COUNTIES IN WV...DRIFTED SW AND HAS NEARLY DISSIPATED AT THIS POINT.
ADDED SLIGHT CHANCE POPS THROUGH 03Z TO CAPTURE THIS...BUT NO OTHER
MAJOR CHANGES MADE.
PREVIOUS DISCUSSION...
RELATIVELY QUIET WEATHER EXPECTED TO CONTINUE IN THE SHORT TERM.
KEPT THE SLIGHT CHANCE FOR SHOWERS IN THE CENTRAL MOUNTAINS THIS
AFTERNOON AS NEAR TERM LOCAL MODELS CONTINUE TO INDICATE THE
POSSIBILITY FOR ELEVATED HEAT SOURCE SHOWERS/THUNDER DEVELOPING
THIS AFTERNOON. OTHERWISE...MAINLY JUST SOME SCATTERED CU THIS
AFTERNOON IN THE DAYTIME HEAT...DISSIPATING WITH THE LOSS OF
HEATING THIS EVENING...AND SCATTERED CIRRUS OVER THE AREA FROM LOW
PRESSURE OFF THE COAST.
NEXT CHANCE FOR SHOWERS WILL OCCUR LATER IN THE DAY ON
SUNDAY...INTO SUNDAY NIGHT...MAINLY EAST...AS MOISTURE FROM THE LOW
OFF THE COAST IS ABLE TO ROTATE INTO THE REGION. BULK OF MOISTURE
LOOKS LIKE IT WILL HOLD OFF UNTIL AFTER THE NEAR TERM PERIOD...BUT
WITH INCREASED MOISTURE AND EASTERLY FLOW...WILL KEEP A MENTION
OVER THE HIGHER TERRAIN COUNTIES SUNDAY AFTERNOON AND EVENING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AREA IS ON WESTERN FRINGES OF MID ATLANTIC STACKED LOW PRESSURE
SYSTEM SUN NT AND MON...BEFORE THAT SYSTEM IS KICKED E BY A NEW
UPSTREAM NORTHERN STREAM S/W TROUGH. SOME OF THE ENERGY FROM THE
NORTHERN STREAM TROUGH GETS FED INTO THE SOUTHERN STREAM...THUS
HELPING TO KICK THE MID ATLANTIC LOW OUT. MAINTAINED THE IDEA OF
CHANCE THUNDERSTORMS MAINLY IN THE MOUNTAINS. A SPOKE OF ENERGY
ROTATING AROUND THE N SIDE OF THE MID ATLANTIC LOW DAMPENS THE
DIURNAL CYCLE AS IT MOVES INTO THE NORTHERN MOUNTAINS MON MORNING.
THE NEW S/W APPROACHES LATE MON AND MOVES ACROSS MON NT THROUGH
TUE. THE THUNDERSTORM CHANCE SHOULD INCREASE FROM THE W LATE MON
GIVEN SFC LOW PRESSURE AND ASSOCIATED CONVERGENCE THERE...THE
APPROACH OF THE UPPER LEVEL SYSTEM...AND THE INSTABILITY AXIS
LOCATED ALONG THE SFC TROUGH. NAM12 SUGGESTS CAPE TO 2500 J / KG
AND LIX TO -6 AND ABOUT A BUCK AND A THIRD PW. FLOW IS ON THE ORDER
OF TEN KNOTS SO SLOW MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW
VALUES WIND UP HIGHER THAN THAT.
CARRIED HIGH CHANCE SHOWERS AND THUNDERSTORMS WELL INTO TUE NT...AS
IT IS HARD TO DETERMINE MOVEMENT OF CLUSTERS WITHIN THE SLOW MOVING
PARENT SYSTEM. MODEL DIFFERENCES REMAIN AS TO WHETHER THE NEW
SYSTEM SIMPLY TAKES OVER AS A NEW MID ATLANTIC UPPER LEVEL LOW.
THIS FACTORS INTO HOW QUICKLY PRECIPITATION ENDS FROM THE W TUE NT.
CONTINUE WITH A MIDDLE GROUND TO SLOW STANCE HERE...WITH THE GFS
MOST PROGRESSIVE.
BLENDED IN THE MET FOR TEMPERATURES EARLY ON AND THEN THE BIAS
CORRECTED MAV FOR HIGHS TUE...TO BETTER REFLECT TEMPERATURE TRENDS
IN RELATION TO THE UPPER LEVEL SYSTEM THAT ARRIVES FROM THE W. THE
COOLEST PERIOD LOOKS TO BE TUE THROUGH TUE NT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLNS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
JUST LIKE LAST NIGHT...EXPECTING VFR CONDITIONS THROUGH THE
PERIOD...WITH THE EXCEPTION OF SOME MVFR FOG AFTER 06Z IN TYPICAL
RIVER VALLEY LOCATIONS. DEWPOINTS ARE A DEGREE OR TWO LOWER THAN
YESTERDAY AT THIS TIME...SO FOR NOW ONLY HAVE CATEGORIES DROPPING
INTO MVFR. HOWEVER...DEWPOINTS HAVE BEEN RISING OVER THE PAST COUPLE
HOURS...SO WILL HAVE TO WATCH TRENDS.
MOISTURE FOR SHOWERS AND STORMS INCREASES THROUGH THE DAY SUNDAY
OVER THE EASTERN MOUNTAINS...WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS OVER THE MOUNTAINS AFTER 18Z SUN. BRIEF MVFR
CONDITIONS WOULD BE POSSIBLE IN AND AROUND ANY SHOWERS/STORMS THAT
DEVELOP.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 05/20/12
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EDT 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H H H H M H H
HTS CONSISTENCY H H H H H M M M M M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H M L M H H
PKB CONSISTENCY H H H H H M M M M M H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...MZ/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...MZ
000
FXUS61 KPBZ 200205
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1005 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH SUNDAY/...
CI SHIELD FROM SE TS CONTINUES TO PUSH OVER THE UPPER OHIO VALLEY.
HAVE INCREASED CLOUD COVER JUST A BIT OVERNIGHT, PARTICULARLY
ACROSS THE SOUTH.
PREVIOUS DISCUSSION...
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE
EXTENDING FROM THE THE OHIO VALLEY INTO NEW ENGLAND WITH ITS
ASSOCIATED WEAK ANTI-CYCLONIC FLOW CENTERED ACROSS THE OHIO
VALLEY. MEANWHILE, A CLOSED LOW IS LOCATED OFF THE CAROLINA COAST.
AT THE SURFACE, A BROAD AREA OF HIGH PRESSURE IS CENTERED ACROSS
THE NORTHEAST, EXTENDING SOUTHWESTWARD INTO THE REGION.
THE RIDGE WILL SHIFT FURTHER NORTHEAST TONIGHT AND TOMORROW,
ALLOWING FOR DRY WEATHER TO CONTINUE WITH UNSEASONABLY WARM
HIGH TEMPS. SKIES WILL BE MOSTLY CLEAR THROUGH THIS
PERIOD, ASIDE FROM SOME HIGH CIRRUS SPILLING INTO THE AREA AHEAD
OF THE LOW TO THE SOUTHEAST. DESPITE TEMPS IN THE LOW TO MID 80S
FOR HIGHS, DRY AIR IN PLACE ALONG WITH NEAR CALM WINDS AND MOSTLY
CLEAR SKIES OVERNIGHT WILL ALLOW FOR ANOTHER NIGHT OF DECENT
RADIATIONAL COOLING. THUS, LOWS ARE A MAV/MET BLEND, DROPPING TO
NEAR NORMAL SEASONAL VALUES, IN THE LOW TO MID 50S ACROSS THE
AREA. THE GFS INDICATES 850 TEMPS AROUND 15C TOMORROW. THIS WILL
CONTRIBUTE TO YET ANOTHER DAY WITH HIGHS 10-15 DEGREES ABOVE
NORMAL, RANGING FROM THE MID 80S ACROSS THE LOWLANDS TO THE MID
70S ACROSS THE EASTERN RIDGES.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
GFS/ECMWF INDICATE THE RIDGE AXIS BECOMING PINCHED OFF SUNDAY NIGHT
INTO MONDAY AS THE UPPER LOW MOVES INTO VIRGINIA AND A TROUGH MOVES
INTO THE UPPER MIDWEST. THE CLOSED LOW WILL SERVE TO DRAW MOISTURE
INTO THE AREA FROM THE ATLANTIC. WITH THIS IN MIND, THE CHANCE OF
SHOWERS BEGINS SOUTHEAST OF PITTSBURGH ON MONDAY MORNING. IN
ASSOCIATION WITH THE TROUGH, A FRONTAL BOUNDARY WILL CROSS THE OHIO
VALLEY ON MONDAY AFTERNOON. INCREASING MOISTURE AND INSTABILITY
AHEAD OF THIS FEATURE WILL LEAD TO THE CHANCE OF SHOWERS AND
THUNDERSTORMS MONDAY AFTERNOON THROUGH THE EVENING. INCREASED
CLOUD COVERAGE AND COOLER TEMPS ALOFT ASSOCIATED WITH THE LOW
APPROACHING FROM THE SOUTHEAST WILL ALLOW FOR A SLIGHT COOLER DAY
ON MONDAY, WITH HIGH TEMPS AT 5 TO 10 DEGREES ABOVE NORMAL,
RANGING FROM THE LOWER 80S ACROSS EASTERN OHIO TO NEAR 70 ACROSS
THE EASTERN RIDGES.
SOME MODEL UNCERTAINTY ENTERS THE FORECAST IN REGARDS TO THE TROUGH
MOVING INTO THE AREA FROM THE UPPER MIDWEST. ECMWF/NAM SOLUTIONS
MERGE THE UPPER LOW TO THE SOUTHEAST WITH THIS FEATURE INTO A MORE
AMPLIFIED TROUGH ACROSS THE AREA. MEANWHILE, THE GFS MOVES THE UPPER
LOW UP THE EAST COAST AND BRINGS A WEAKER TROUGH ACROSS THE AREA. WITH
THIS UNCERTAINTY IN MIND AND THE SLOW PASSAGE OF A FRONTAL
BOUNDARY, FORECAST IS A BLEND OF THE SOLUTIONS, CONTINUING A
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY.
WITH INCREASED CLOUD COVERAGE WITH SHOWERS AND THUNDERSTORMS,
HIGHS ON TUESDAY WILL BE SLIGHTLY COOLER IN COMPARISON TO THE
WEEKEND AND MONDAY, ALTHOUGH STILL AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR AND WINDS BELOW 10 KTS
FOR NEXT 24 HOURS. THE ONLY CLOUDS THAT ARE EXPECTED WILL BE WITH
BLOWOFF FROM POSSIBLE TROPICAL SYSTEM OFF CAROLINAS.
.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY. CONVECTION WILL ALSO INCREASE FROM THE EAST. SLOW
MOVING FRONT WILL BRING A CONTINUED CHANCE FOR SHOWERS AND
THUNDERSTORMS THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT
EAST OF THE AREA BY WEDNESDAY NIGHT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 200147
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
947 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH TOMORROW AND THEN MOVE OFF THE EAST COAST ON MONDAY. A
COLD FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM
THE WEST WHILE LOW PRESSURE MOVES NORTH ALONG THE MID ATLANTIC
COAST MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE
EAST ON TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
GOING FORECAST REMAINS ON TRACK. CIRRUS CONTINUES TO THIN AS IT
SPREADS NORTH ACROSS EASTERN OHIO/WESTERN PA AND SHOULD NOT HAVE A
LIMITING EFFECT ON MINS FOR TONIGHT.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE AREA TONIGHT WILL ALLOW FOR
MAINLY CLEAR SKIES AND QUIET CONDITIONS. SOME CIRRUS CLOUDS MOVING
NORTHWARD INTO EASTERN AREAS...BUT NOT ENOUGH COVERAGE IN GRIDS TO
MENTION PARTLY CLOUDY. MAINLY MOSTLY CLEAR SKIES TONIGHT. USED A
BLEND OF MET AND MAV TEMPS...WITH LOWER 50S IN THE GOOD RADIATING
SPOTS. WOULD NOT BE SURPRISED TO SEE UPPER 40S ACROSS THE INTERIOR
OF NW PA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAIN ACROSS THE AREA ON SUNDAY WITH TEMPS SIMILAR
OR A BIT WARMER...WITH A LAKE BREEZE LIKELY IN THE AFTERNOON.
THERE MAY BE SOME CIRRUS CLOUDS ACROSS THE EAST AGAIN BUT NOT MUCH
IMPACT ON THE MOSTLY SUNNY SKIES. LOWS WARMER SUNDAY NIGHT AS A
COLD FRONT APPROACHES FROM THE WEST.
MODELS SHOWING A COLD FRONT APPROACHING THE AREA MONDAY. FOR NOW
WENT WITH MAINLY DRY CONDITIONS IN THE MORNING WITH INCREASING
POPS ACROSS THE WEST IN THE AFTERNOON. MEANWHILE...MOISTURE
SPREADING WESTWARD FROM LOW PRESSURE ALONG THE EAST COAST. WHILE
THERE IS STILL SOME DISCREPANCIES AS TO HOW FAR PRECIP WILL GET
ACROSS THE APPALACHIANS THERE WILL AT LEAST BE INCREASING CLOUDS.
MENTION LOW CHC POPS ACROSS THE FAR EAST INCLUDING NW PA IN THE
AFTERNOON...WITH CHC POPS ALSO ACROSS THE WEST WITH THE COLD FRONT
APPROACHING. CENTRAL LOCATIONS FROM CLE-MFD ONLY HAVE SLGT UNTIL
MONDAY NIGHT.
BETWEEN THE FRONT AND ANY POSSIBLE SHOWERS FROM MOISTURE BY THE
EAST COAST LOW LOOKS LIKE THERE WILL BE AT LEAST A CHANCE FOR
SHRA/TS MONDAY NIGHT ACROSS THE ENTIRE AREA. GIVEN INCREASING
DEWPOINTS ACROSS THE AREA KEEP LOWS AROUND 60 FOR MUCH OF THE
AREA.
MODELS SHOWING AN UPPER TROUGH OVER THE OHIO VALLEY SOUTH OF THE
AREA THROUGH TUESDAY...SO GIVEN SOME REMAINING INSTABILITY ACROSS
THE AREA CHC POPS FOR SHRA/THUNDERSTORMS CONTINUE. GFS A BIT
QUICKER THAN 12Z ECMWF IN BRINGING IN HIGH PRESSURE THROUGH
TUESDAY NIGHT. ALLOWED WESTERN AREAS TO DRY OUT TUESDAY NIGHT
WHILE LOWERING POPS TO SLGT CHC/LOW CHC ACROSS THE FAR EAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS NOT IN COMPLETE AGREEMENT. THE GFS HAS AN UPPER RIDGE
ACROSS THE REGION WEDNESDAY WHILE THE 12Z ECMWF HAS AN UPPER LOW
OVER THE TENNESSEE VALLEY THAT WILL VERY SLOWLY MOVE SOUTHEAST
THROUGH THURSDAY NIGHT. IF THE ECMWF IS CORRECT THIS COULD MEAN A
THREAT OF PRECIPITATION WILL HANG ON OVER NORTHEAST OHIO AND
NORTHWEST PA INTO THURSDAY NIGHT. BECAUSE OF THE UNCERTAINTY KEPT
LOW CHANCE POPS INTO WEDNESDAY FOR THE EASTERN PORTION OF THE
FORECAST AREA AND THEN DRY AFTER THAT. THIS WILL HAVE TO BE
MONITORED.
BY THE END OF THE WEEK A RIDGE ALOFT WILL BE OVER THE AREA WITH
PLENTY OF WARM TEMPERATURES AND HIGHS NEAR 90. OTHERWISE WENT CLOSE
TO HPC FOR TEMPERATURES.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE INTO SUNDAY EVENING. THE ONLY
DIFFERENCE FROM TODAY WILL BE AN INCREASE OF HIGH LEVEL CLOUD
COVER. THERE MAY ALSO BE A FEW CUMULUS IN THE VICINITY OF KFDY BY
MID TO LATE AFTERNOON. WINDS WILL BE SIMILAR AGAIN ON SUNDAY WITH
A GENERAL SOUTHEAST TO SOUTH FLOW AWAY FROM THE LAKE. LAKE BREEZE
TIMING WILL BE VERY SIMILAR TO THIS AFTERNOON WITH IT REACHING
KCLE AROUND 19Z...KERI AROUND 16Z AND KTOL BY 22Z.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
THUNDERSTORMS MONDAY AFTERNOON INTO WEDNESDAY. EARLY MORNING
FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WORK WEEK...HOWEVER...FORECASTS WILL HAVE TO BE
MONITORED BECAUSE OF MODEL UNCERTAINTY.
THE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY WEAKEN ON
SUNDAY. A WEAK COLD FRONT WILL MOVE ACROSS THE LAKE MONDAY INTO
MONDAY NIGHT. THE WINDS WILL BE ONSHORE BEHIND THE FRONT BUT IT
LOOKS LIKE THEY WILL BE WEAK ENOUGH THAT A SMALL CRAFT ADVISORY MAY
NOT BE NEEDED. HIGH PRESSURE BUILDS BACK IN BY LATE TUESDAY AND THEN
THE RIDGE MOVES EAST WEDNESDAY AND THE AREA GETS INTO A SOUTHWEST OR
SOUTH FLOW. THE NEXT FRONTAL SYSTEM MOVES TOWARD THE LAKE FOR THE
EARLY PART OF NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/KEC
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...KIELTYKA
000
FXUS61 KILN 192356
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
756 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE WEEKEND. A SLOW
MOVING FRONT WILL MOVE EAST INTO THE OHIO VALLEY ON
MONDAY...PROVIDING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY. DRY WEATHER AND WARMING TEMPERATURES WILL BE IN PLACE FOR
THE REST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SURFACE MOISTURE HAS DECREASED SOMEWHAT DURING THE DAY TODAY...AS
TEMPERATURES HAVE RISEN WELL INTO THE 80S UNDER HIGH PRESSURE AND
CLEAR CONDITIONS. THE ATMOSPHERE OVER THE CWA IS CAPPED...LIMITING
CLOUD DEVELOPMENT TO FLAT...HIGH BASED CUMULUS. IN OVERALL WEAK
FLOW...MODEL AGREEMENT THROUGH THE NEAR TERM IS STRONG OVER THE
MIDDLE OHIO VALLEY. MIN TEMPERATURES WERE RAISED SLIGHTLY IN THE
WEST...AS MOISTURE WILL SLOWLY BEGIN TO INCREASE OVERNIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS WIND FLOW TURNS MORE SOUTHERLY ON SUNDAY...MOISTURE WILL
CONTINUE TO INCREASE SLIGHTLY OVER THE REGION. WITH LESS CAPPING
AND HIGHER DEWPOINTS...SOME INSTABILITY WILL BE
PRESENT...ESPECIALLY IN THE SOUTHWEST. HOWEVER...HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE OVERALL PATTERN...WITH NO SIGNS OF
ANY TRIGGER FOR CONVECTION. THIS MAY BE A SITUATION WHERE A VERY
ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE DURING THE DIURNAL
HEATING CYCLE...AND MAINLY IN THE WEST AND SOUTHWEST PARTS OF THE
CWA. WOULD BEST CATEGORIZE THIS AS A 10-PERCENT POP FOR NOW.
AS A POTENTIAL TROPICAL SYSTEM MOVES NEAR THE COAST...A SLOW
MOVING COLD FRONT ON A SSW-TO-NNE ORIENTATION WILL MOVE INTO THE
OHIO VALLEY. WHILE THIS MAY PRESENT SOME FORECAST DIFFICULTY AS
THE FEATURES INTERACT OVER THE APPALACHIANS...AT THIS TIME THERE
IS HIGH CONFIDENCE THAT THE PROGRESS OF THE FRONT WILL BE LARGELY
UNIMPEDED (THOUGH SLOW) FOR THE ILN FORECAST AREA.
INSTABILITY WILL BE PRESENT AHEAD OF THE FRONT AND WEAK SURFACE
LOW...GENERALLY AROUND 1000 J/KG OF MLCAPE PER GFS AND NAM
DEPICTIONS. THE SLOW MOTION OF THE FRONT AND WEAK WIND FIELDS SEEM
TO PRECLUDE SEVERE WEATHER THREATS...THOUGH THE SLOW MOTION MAY
SUPPORT SOME LOCALLY HEAVY RAINFALL.
MIN TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE
OF GUIDANCE...ESPECIALLY SUNDAY NIGHT AND MONDAY NIGHT. THE RAW NAM
TEMPERATURES CAPTURE THE IMPACTS OF THE FRONTAL SYSTEM AND THE
MOIST AIR MASS ASSOCIATED WITH IT. DEPENDING ON THE RAINFALL
PATTERNS...HIGHS ON MONDAY IN THE WESTERN HALF OF THE CWA MAY COME
EARLIER IN THE DAY THAN NORMAL. THERE IS GOOD AGREEMENT IN THE
MODELS ON MONDAY BEING AROUND 5 DEGREES COOLER THAN
SUNDAY IN THE WEST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
WILL SIDE WITH AN HPC SOLUTION FOR THE EXTENDED FORECAST. THIS
SOLUTION TAKES A BLEND OF THE GFS AND ECMWF IN REGARDS TO UPR LVL
TROUGH POSITION/MOVEMENT FOR THE TUESDAY THROUGH THURSDAY TIME FRAME.
FORECAST WILL ALLOW UPR LVL TROUGH TO GRADUALLY MOVE OFF TO THE EAST
AND CLOSE OFF. CONFIDENCE IS NOT THE HIGHEST WITH THIS SOLUTION AS
MODELS TYPICALLY STRUGGLE WITH HOW UPR TROUGHS CLOSE OFF AND
PROGRESS THEREAFTER. SO IT WILL BEHOOVE ONE TO MONITOR LATER
FORECASTS. MODELS SEEM TO AGREE THAT BY WEEKS END AN UPR LVL RIDGE
WILL BUILD ACRS THE OHIO VALLEY. AS FOR TEMPERATURES...THEY WILL
START OFF NEAR NORMAL TUESDAY AND WEDNESDAY...THEN GRADUALLY WARM TO
ABOVE NORMAL READINGS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AFTN CU HAVE DISSIPATED OVER THE SRN TAFS...BUT SOME CI FROM
TROPICAL STORM ALBERTO IS WORKING W INTO THE TAFS. NAM AND GFS ARE
SUGGESTING THAT THE CI COULD GO BROKEN AT TIMES OVERNIGHT AT THE
ERN TAFS.
OTHER THAN THAT...THE TAFS WILL REMAIN SANDWICHED BETWEEN A
DIGGING H5 TROF TO THE W AND ALBERTO TO THE E. CURU IS INDICATING
THAT THE BEST CU WILL POP ACROSS INDIANA TOMORROW...LEAVING THE
WRN TAFS ON THE FRINGE...WITH LITTLE CU IN THE E.
WEAK SE FLOW OVERNIGHT....SO ALLOW IFR FOG AGAIN AT LUK BETWEEN
09Z-12Z.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
000
FXUS61 KCLE 192339
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
739 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH TOMORROW AND THEN MOVE OFF THE EAST COAST ON MONDAY. A
COLD FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM
THE WEST WHILE LOW PRESSURE MOVES NORTH ALONG THE MID ATLANTIC
COAST MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE
EAST ON TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
GOING FORECAST REMAINS ON TRACK. EXPECT TEMPERATURES TO DROP
QUICKLY AFTER SUNSET WITH LIGHT WINDS AND DRY AIRMASS.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE AREA TONIGHT WILL ALLOW FOR
MAINLY CLEAR SKIES AND QUIET CONDITIONS. SOME CIRRUS CLOUDS MOVING
NORTHWARD INTO EASTERN AREAS...BUT NOT ENOUGH COVERAGE IN GRIDS TO
MENTION PARTLY CLOUDY. MAINLY MOSTLY CLEAR SKIES TONIGHT. USED A
BLEND OF MET AND MAV TEMPS...WITH LOWER 50S IN THE GOOD RADIATING
SPOTS. WOULD NOT BE SURPRISED TO SEE UPPER 40S ACROSS THE INTERIOR
OF NW PA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAIN ACROSS THE AREA ON SUNDAY WITH TEMPS SIMILAR
OR A BIT WARMER...WITH A LAKE BREEZE LIKELY IN THE AFTERNOON.
THERE MAY BE SOME CIRRUS CLOUDS ACROSS THE EAST AGAIN BUT NOT MUCH
IMPACT ON THE MOSTLY SUNNY SKIES. LOWS WARMER SUNDAY NIGHT AS A
COLD FRONT APPROACHES FROM THE WEST.
MODELS SHOWING A COLD FRONT APPROACHING THE AREA MONDAY. FOR NOW
WENT WITH MAINLY DRY CONDITIONS IN THE MORNING WITH INCREASING
POPS ACROSS THE WEST IN THE AFTERNOON. MEANWHILE...MOISTURE
SPREADING WESTWARD FROM LOW PRESSURE ALONG THE EAST COAST. WHILE
THERE IS STILL SOME DISCREPANCIES AS TO HOW FAR PRECIP WILL GET
ACROSS THE APPALACHIANS THERE WILL AT LEAST BE INCREASING CLOUDS.
MENTION LOW CHC POPS ACROSS THE FAR EAST INCLUDING NW PA IN THE
AFTERNOON...WITH CHC POPS ALSO ACROSS THE WEST WITH THE COLD FRONT
APPROACHING. CENTRAL LOCATIONS FROM CLE-MFD ONLY HAVE SLGT UNTIL
MONDAY NIGHT.
BETWEEN THE FRONT AND ANY POSSIBLE SHOWERS FROM MOISTURE BY THE
EAST COAST LOW LOOKS LIKE THERE WILL BE AT LEAST A CHANCE FOR
SHRA/TS MONDAY NIGHT ACROSS THE ENTIRE AREA. GIVEN INCREASING
DEWPOINTS ACROSS THE AREA KEEP LOWS AROUND 60 FOR MUCH OF THE
AREA.
MODELS SHOWING AN UPPER TROUGH OVER THE OHIO VALLEY SOUTH OF THE
AREA THROUGH TUESDAY...SO GIVEN SOME REMAINING INSTABILITY ACROSS
THE AREA CHC POPS FOR SHRA/THUNDERSTORMS CONTINUE. GFS A BIT
QUICKER THAN 12Z ECMWF IN BRINGING IN HIGH PRESSURE THROUGH
TUESDAY NIGHT. ALLOWED WESTERN AREAS TO DRY OUT TUESDAY NIGHT
WHILE LOWERING POPS TO SLGT CHC/LOW CHC ACROSS THE FAR EAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS NOT IN COMPLETE AGREEMENT. THE GFS HAS AN UPPER RIDGE
ACROSS THE REGION WEDNESDAY WHILE THE 12Z ECMWF HAS AN UPPER LOW
OVER THE TENNESSEE VALLEY THAT WILL VERY SLOWLY MOVE SOUTHEAST
THROUGH THURSDAY NIGHT. IF THE ECMWF IS CORRECT THIS COULD MEAN A
THREAT OF PRECIPITATION WILL HANG ON OVER NORTHEAST OHIO AND
NORTHWEST PA INTO THURSDAY NIGHT. BECAUSE OF THE UNCERTAINTY KEPT
LOW CHANCE POPS INTO WEDNESDAY FOR THE EASTERN PORTION OF THE
FORECAST AREA AND THEN DRY AFTER THAT. THIS WILL HAVE TO BE
MONITORED.
BY THE END OF THE WEEK A RIDGE ALOFT WILL BE OVER THE AREA WITH
PLENTY OF WARM TEMPERATURES AND HIGHS NEAR 90. OTHERWISE WENT CLOSE
TO HPC FOR TEMPERATURES.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE INTO SUNDAY EVENING. THE ONLY
DIFFERENCE FROM TODAY WILL BE AN INCREASE OF HIGH LEVEL CLOUD
COVER. THERE MAY ALSO BE A FEW CUMULUS IN THE VICINITY OF KFDY BY
MID TO LATE AFTERNOON. WINDS WILL BE SIMILAR AGAIN ON SUNDAY WITH
A GENERAL SOUTHEAST TO SOUTH FLOW AWAY FROM THE LAKE. LAKE BREEZE
TIMING WILL BE VERY SIMILAR TO THIS AFTERNOON WITH IT REACHING
KCLE AROUND 19Z...KERI AROUND 16Z AND KTOL BY 22Z.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
THUNDERSTORMS MONDAY AFTERNOON INTO WEDNESDAY. EARLY MORNING
FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.
&&
.MARINE...
NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WORK WEEK...HOWEVER...FORECASTS WILL HAVE TO BE
MONITORED BECAUSE OF MODEL UNCERTAINTY.
THE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY WEAKEN ON
SUNDAY. A WEAK COLD FRONT WILL MOVE ACROSS THE LAKE MONDAY INTO
MONDAY NIGHT. THE WINDS WILL BE ONSHORE BEHIND THE FRONT BUT IT
LOOKS LIKE THEY WILL BE WEAK ENOUGH THAT A SMALL CRAFT ADVISORY MAY
NOT BE NEEDED. HIGH PRESSURE BUILDS BACK IN BY LATE TUESDAY AND THEN
THE RIDGE MOVES EAST WEDNESDAY AND THE AREA GETS INTO A SOUTHWEST OR
SOUTH FLOW. THE NEXT FRONTAL SYSTEM MOVES TOWARD THE LAKE FOR THE
EARLY PART OF NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/KEC
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...KIELTYKA
000
FXUS61 KRLX 192325
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
725 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE INTO SUNDAY. LOW PRESSURE CLOSE BY TO THE EAST LATE
SUNDAY THROUGH MONDAY GETS KICKED OUT BY SYSTEM COMING FROM THE WEST
MONDAY NIGHT. THE NEW SYSTEM CROSSES TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH SUNDAY/...
720 PM UPDATE...NO SIGNIFICANT CHANGES NEEDED...TOUCHED UP HOURLY
GRIDS BASED ON CURRENT OBS/TRENDS.
PREVIOUS DISCUSSION...
RELATIVELY QUIET WEATHER EXPECTED TO CONTINUE IN THE SHORT TERM.
KEPT THE SLIGHT CHANCE FOR SHOWERS IN THE CENTRAL MOUNTAINS THIS
AFTERNOON AS NEAR TERM LOCAL MODELS CONTINUE TO INDICATE THE
POSSIBILITY FOR ELEVATED HEAT SOURCE SHOWERS/THUNDER DEVELOPING
THIS AFTERNOON. OTHERWISE...MAINLY JUST SOME SCATTERED CU THIS
AFTERNOON IN THE DAYTIME HEAT...DISSIPATING WITH THE LOSS OF
HEATING THIS EVENING...AND SCATTERED CIRRUS OVER THE AREA FROM LOW
PRESSURE OFF THE COAST.
NEXT CHANCE FOR SHOWERS WILL OCCUR LATER IN THE DAY ON
SUNDAY...INTO SUNDAY NIGHT...MAINLY EAST...AS MOISTURE FROM THE LOW
OFF THE COAST IS ABLE TO ROTATE INTO THE REGION. BULK OF MOISTURE
LOOKS LIKE IT WILL HOLD OFF UNTIL AFTER THE NEAR TERM PERIOD...BUT
WITH INCREASED MOISTURE AND EASTERLY FLOW...WILL KEEP A MENTION
OVER THE HIGHER TERRAIN COUNTIES SUNDAY AFTERNOON AND EVENING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AREA IS ON WESTERN FRINGES OF MID ATLANTIC STACKED LOW PRESSURE
SYSTEM SUN NT AND MON...BEFORE THAT SYSTEM IS KICKED E BY A NEW
UPSTREAM NORTHERN STREAM S/W TROUGH. SOME OF THE ENERGY FROM THE
NORTHERN STREAM TROUGH GETS FED INTO THE SOUTHERN STREAM...THUS
HELPING TO KICK THE MID ATLANTIC LOW OUT. MAINTAINED THE IDEA OF
CHANCE THUNDERSTORMS MAINLY IN THE MOUNTAINS. A SPOKE OF ENERGY
ROTATING AROUND THE N SIDE OF THE MID ATLANTIC LOW DAMPENS THE
DIURNAL CYCLE AS IT MOVES INTO THE NORTHERN MOUNTAINS MON MORNING.
THE NEW S/W APPROACHES LATE MON AND MOVES ACROSS MON NT THROUGH
TUE. THE THUNDERSTORM CHANCE SHOULD INCREASE FROM THE W LATE MON
GIVEN SFC LOW PRESSURE AND ASSOCIATED CONVERGENCE THERE...THE
APPROACH OF THE UPPER LEVEL SYSTEM...AND THE INSTABILITY AXIS
LOCATED ALONG THE SFC TROUGH. NAM12 SUGGESTS CAPE TO 2500 J / KG
AND LIX TO -6 AND ABOUT A BUCK AND A THIRD PW. FLOW IS ON THE ORDER
OF TEN KNOTS SO SLOW MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW
VALUES WIND UP HIGHER THAN THAT.
CARRIED HIGH CHANCE SHOWERS AND THUNDERSTORMS WELL INTO TUE NT...AS
IT IS HARD TO DETERMINE MOVEMENT OF CLUSTERS WITHIN THE SLOW MOVING
PARENT SYSTEM. MODEL DIFFERENCES REMAIN AS TO WHETHER THE NEW
SYSTEM SIMPLY TAKES OVER AS A NEW MID ATLANTIC UPPER LEVEL LOW.
THIS FACTORS INTO HOW QUICKLY PRECIPITATION ENDS FROM THE W TUE NT.
CONTINUE WITH A MIDDLE GROUND TO SLOW STANCE HERE...WITH THE GFS
MOST PROGRESSIVE.
BLENDED IN THE MET FOR TEMPERATURES EARLY ON AND THEN THE BIAS
CORRECTED MAV FOR HIGHS TUE...TO BETTER REFLECT TEMPERATURE TRENDS
IN RELATION TO THE UPPER LEVEL SYSTEM THAT ARRIVES FROM THE W. THE
COOLEST PERIOD LOOKS TO BE TUE THROUGH TUE NT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLNS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
JUST LIKE LAST NIGHT...EXPECTING VFR CONDITIONS THROUGH THE
PERIOD...WITH THE EXCEPTION OF SOME MVFR FOG AFTER 06Z IN TYPICAL
RIVER VALLEY LOCATIONS. DEWPOINTS ARE A DEGREE OR TWO LOWER THAN
YESTERDAY AT THIS TIME...SO FOR NOW ONLY HAVE CATEGORIES DROPPING
INTO MVFR. HOWEVER...DEWPOINTS HAVE BEEN RISING OVER THE PAST COUPLE
HOURS...SO WILL HAVE TO WATCH TRENDS.
MOISTURE FOR SHOWERS AND STORMS INCREASES THROUGH THE DAY SUNDAY
OVER THE EASTERN MOUNTAINS...WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS OVER THE MOUNTAINS AFTER 18Z SUN. BRIEF MVFR
CONDITIONS WOULD BE POSSIBLE IN AND AROUND ANY SHOWERS/STORMS THAT
DEVELOP.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...MZ/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...MZ
000
FXUS61 KCLE 192240
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
640 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH TOMORROW AND THEN MOVE OFF THE EAST COAST ON MONDAY. A
COLD FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM
THE WEST WHILE LOW PRESSURE MOVES NORTH ALONG THE MID ATLANTIC
COAST MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE
EAST ON TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
GOING FORECAST REMAINS ON TRACK. EXPECT TEMPERATURES TO DROP
QUICKLY AFTER SUNSET WITH LIGHT WINDS AND DRY AIRMASS.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE AREA TONIGHT WILL ALLOW FOR
MAINLY CLEAR SKIES AND QUIET CONDITIONS. SOME CIRRUS CLOUDS MOVING
NORTHWARD INTO EASTERN AREAS...BUT NOT ENOUGH COVERAGE IN GRIDS TO
MENTION PARTLY CLOUDY. MAINLY MOSTLY CLEAR SKIES TONIGHT. USED A
BLEND OF MET AND MAV TEMPS...WITH LOWER 50S IN THE GOOD RADIATING
SPOTS. WOULD NOT BE SURPRISED TO SEE UPPER 40S ACROSS THE INTERIOR
OF NW PA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAIN ACROSS THE AREA ON SUNDAY WITH TEMPS SIMILAR
OR A BIT WARMER...WITH A LAKE BREEZE LIKELY IN THE AFTERNOON.
THERE MAY BE SOME CIRRUS CLOUDS ACROSS THE EAST AGAIN BUT NOT MUCH
IMPACT ON THE MOSTLY SUNNY SKIES. LOWS WARMER SUNDAY NIGHT AS A
COLD FRONT APPROACHES FROM THE WEST.
MODELS SHOWING A COLD FRONT APPROACHING THE AREA MONDAY. FOR NOW
WENT WITH MAINLY DRY CONDITIONS IN THE MORNING WITH INCREASING
POPS ACROSS THE WEST IN THE AFTERNOON. MEANWHILE...MOISTURE
SPREADING WESTWARD FROM LOW PRESSURE ALONG THE EAST COAST. WHILE
THERE IS STILL SOME DISCREPANCIES AS TO HOW FAR PRECIP WILL GET
ACROSS THE APPALACHIANS THERE WILL AT LEAST BE INCREASING CLOUDS.
MENTION LOW CHC POPS ACROSS THE FAR EAST INCLUDING NW PA IN THE
AFTERNOON...WITH CHC POPS ALSO ACROSS THE WEST WITH THE COLD FRONT
APPROACHING. CENTRAL LOCATIONS FROM CLE-MFD ONLY HAVE SLGT UNTIL
MONDAY NIGHT.
BETWEEN THE FRONT AND ANY POSSIBLE SHOWERS FROM MOISTURE BY THE
EAST COAST LOW LOOKS LIKE THERE WILL BE AT LEAST A CHANCE FOR
SHRA/TS MONDAY NIGHT ACROSS THE ENTIRE AREA. GIVEN INCREASING
DEWPOINTS ACROSS THE AREA KEEP LOWS AROUND 60 FOR MUCH OF THE
AREA.
MODELS SHOWING AN UPPER TROUGH OVER THE OHIO VALLEY SOUTH OF THE
AREA THROUGH TUESDAY...SO GIVEN SOME REMAINING INSTABILITY ACROSS
THE AREA CHC POPS FOR SHRA/THUNDERSTORMS CONTINUE. GFS A BIT
QUICKER THAN 12Z ECMWF IN BRINGING IN HIGH PRESSURE THROUGH
TUESDAY NIGHT. ALLOWED WESTERN AREAS TO DRY OUT TUESDAY NIGHT
WHILE LOWERING POPS TO SLGT CHC/LOW CHC ACROSS THE FAR EAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS NOT IN COMPLETE AGREEMENT. THE GFS HAS AN UPPER RIDGE
ACROSS THE REGION WEDNESDAY WHILE THE 12Z ECMWF HAS AN UPPER LOW
OVER THE TENNESSEE VALLEY THAT WILL VERY SLOWLY MOVE SOUTHEAST
THROUGH THURSDAY NIGHT. IF THE ECMWF IS CORRECT THIS COULD MEAN A
THREAT OF PRECIPITATION WILL HANG ON OVER NORTHEAST OHIO AND
NORTHWEST PA INTO THURSDAY NIGHT. BECAUSE OF THE UNCERTAINTY KEPT
LOW CHANCE POPS INTO WEDNESDAY FOR THE EASTERN PORTION OF THE
FORECAST AREA AND THEN DRY AFTER THAT. THIS WILL HAVE TO BE
MONITORED.
BY THE END OF THE WEEK A RIDGE ALOFT WILL BE OVER THE AREA WITH
PLENTY OF WARM TEMPERATURES AND HIGHS NEAR 90. OTHERWISE WENT CLOSE
TO HPC FOR TEMPERATURES.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR FOR THE TAF PERIOD. HIGH PRESSURE RIDGE ACROSS THE FORECAST
AREA WILL PERSIST INTO SUNDAY. A LAKE BREEZE HAS DEVELOPED AND
WILL CONTINUE THRU SUNSET. SOME THIN CIRRUS WILL SPREAD FROM SOUTH TO
NORTH INTO TONIGHT BECAUSE OF AN UPPER LOW OVER THE SOUTHEAST STATES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON AND POSSIBLY CONTINUING THROUGH WEDNESDAY NIGHT.
&&
.MARINE...
NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WORK WEEK...HOWEVER...FORECASTS WILL HAVE TO BE
MONITORED BECAUSE OF MODEL UNCERTAINTY.
THE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY WEAKEN ON
SUNDAY. A WEAK COLD FRONT WILL MOVE ACROSS THE LAKE MONDAY INTO
MONDAY NIGHT. THE WINDS WILL BE ONSHORE BEHIND THE FRONT BUT IT
LOOKS LIKE THEY WILL BE WEAK ENOUGH THAT A SMALL CRAFT ADVISORY MAY
NOT BE NEEDED. HIGH PRESSURE BUILDS BACK IN BY LATE TUESDAY AND THEN
THE RIDGE MOVES EAST WEDNESDAY AND THE AREA GETS INTO A SOUTHWEST OR
SOUTH FLOW. THE NEXT FRONTAL SYSTEM MOVES TOWARD THE LAKE FOR THE
EARLY PART OF NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/KEC
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
000
FXUS61 KPBZ 192219 AAA
AFDPBZ
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
619 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH SUNDAY/...
MINOR CHANGES TO PREVIOUS FORECAST, INCREASED OVERNIGHT LOWS A
COUPLE OF DEGREES AND MADE TWEAKS TO CLOUD COVER.
PREVIOUS DISCUSSION...
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE
EXTENDING FROM THE THE OHIO VALLEY INTO NEW ENGLAND WITH ITS
ASSOCIATED WEAK ANTI-CYCLONIC FLOW CENTERED ACROSS THE OHIO
VALLEY. MEANWHILE, A CLOSED LOW IS LOCATED OFF THE CAROLINA COAST.
AT THE SURFACE, A BROAD AREA OF HIGH PRESSURE IS CENTERED ACROSS
THE NORTHEAST, EXTENDING SOUTHWESTWARD INTO THE REGION.
THE RIDGE WILL SHIFT FURTHER NORTHEAST TONIGHT AND TOMORROW,
ALLOWING FOR DRY WEATHER TO CONTINUE WITH UNSEASONABLY WARM
HIGH TEMPS. SKIES WILL BE MOSTLY CLEAR THROUGH THIS
PERIOD, ASIDE FROM SOME HIGH CIRRUS SPILLING INTO THE AREA AHEAD
OF THE LOW TO THE SOUTHEAST. DESPITE TEMPS IN THE LOW TO MID 80S
FOR HIGHS, DRY AIR IN PLACE ALONG WITH NEAR CALM WINDS AND MOSTLY
CLEAR SKIES OVERNIGHT WILL ALLOW FOR ANOTHER NIGHT OF DECENT
RADIATIONAL COOLING. THUS, LOWS ARE A MAV/MET BLEND, DROPPING TO
NEAR NORMAL SEASONAL VALUES, IN THE LOW TO MID 50S ACROSS THE
AREA. THE GFS INDICATES 850 TEMPS AROUND 15C TOMORROW. THIS WILL
CONTRIBUTE TO YET ANOTHER DAY WITH HIGHS 10-15 DEGREES ABOVE
NORMAL, RANGING FROM THE MID 80S ACROSS THE LOWLANDS TO THE MID
70S ACROSS THE EASTERN RIDGES.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
GFS/ECMWF INDICATE THE RIDGE AXIS BECOMING PINCHED OFF SUNDAY NIGHT
INTO MONDAY AS THE UPPER LOW MOVES INTO VIRGINIA AND A TROUGH MOVES
INTO THE UPPER MIDWEST. THE CLOSED LOW WILL SERVE TO DRAW MOISTURE
INTO THE AREA FROM THE ATLANTIC. WITH THIS IN MIND, THE CHANCE OF
SHOWERS BEGINS SOUTHEAST OF PITTSBURGH ON MONDAY MORNING. IN
ASSOCIATION WITH THE TROUGH, A FRONTAL BOUNDARY WILL CROSS THE OHIO
VALLEY ON MONDAY AFTERNOON. INCREASING MOISTURE AND INSTABILITY
AHEAD OF THIS FEATURE WILL LEAD TO THE CHANCE OF SHOWERS AND
THUNDERSTORMS MONDAY AFTERNOON THROUGH THE EVENING. INCREASED
CLOUD COVERAGE AND COOLER TEMPS ALOFT ASSOCIATED WITH THE LOW
APPROACHING FROM THE SOUTHEAST WILL ALLOW FOR A SLIGHT COOLER DAY
ON MONDAY, WITH HIGH TEMPS AT 5 TO 10 DEGREES ABOVE NORMAL,
RANGING FROM THE LOWER 80S ACROSS EASTERN OHIO TO NEAR 70 ACROSS
THE EASTERN RIDGES.
SOME MODEL UNCERTAINTY ENTERS THE FORECAST IN REGARDS TO THE TROUGH
MOVING INTO THE AREA FROM THE UPPER MIDWEST. ECMWF/NAM SOLUTIONS
MERGE THE UPPER LOW TO THE SOUTHEAST WITH THIS FEATURE INTO A MORE
AMPLIFIED TROUGH ACROSS THE AREA. MEANWHILE, THE GFS MOVES THE UPPER
LOW UP THE EAST COAST AND BRINGS A WEAKER TROUGH ACROSS THE AREA. WITH
THIS UNCERTAINTY IN MIND AND THE SLOW PASSAGE OF A FRONTAL
BOUNDARY, FORECAST IS A BLEND OF THE SOLUTIONS, CONTINUING A
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY.
WITH INCREASED CLOUD COVERAGE WITH SHOWERS AND THUNDERSTORMS,
HIGHS ON TUESDAY WILL BE SLIGHTLY COOLER IN COMPARISON TO THE
WEEKEND AND MONDAY, ALTHOUGH STILL AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR AND WINDS BELOW 10 KTS
FOR NEXT 24 HOURS. THE ONLY CLOUDS THAT ARE EXPECTED WILL BE WITH
BLOWOFF FROM POSSIBLE TROPICAL SYSTEM OFF CAROLINAS.
.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY. CONVECTION WILL ALSO INCREASE FROM THE EAST. SLOW
MOVING FRONT WILL BRING A CONTINUED CHANCE FOR SHOWERS AND
THUNDERSTORMS THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT
EAST OF THE AREA BY WEDNESDAY NIGHT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 192022
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
422 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE INTO SUNDAY. LOW PRESSURE CLOSE BY TO THE EAST LATE
SUNDAY THROUGH MONDAY GETS KICKED OUT BY SYSTEM COMING FROM THE WEST
MONDAY NIGHT. THE NEW SYSTEM CROSSES TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH SUNDAY/...
COLD FRONT...AT 18Z WAS LOCATED JUST NORTH OF SOUTHEAST OHIO
ZONES...AND PUSHING SOUTH TOWARDS THE REGION. BEHIND THE
FRONT...CONVECTIVE SHOWERS/STORMS HAVE FIRED ACROSS NORTHERN OHIO
AND WESTERN PA. AS THE COLD FRONT CONTINUES TO PUSH SOUTH TOWARDS
OUR REGION...WILL SEE AN INCREASE IN CLOUD COVER...AND A CHANCE FOR
ISOLD CONVECTIVE SHOWERS/THUNDERSTORMS. FRONT WILL PUSH SOUTH AND
END UP IN CENTRAL PART OF CWA...NEAR/ALONG LINE FROM CRW TO
CKB...AROUND 00Z. WITH OVERALL LIMITED MOISTURE AND DYNAMICS WITH
FRONT...AND LOSS OF DAYTIME HEATING...EXPECT CHANCES FOR
PRECIPITATION TO FIZZLE OUT AROUND OR SHORTLY AFTER 00Z. FRONTAL
BOUNDARY WILL EXIT TO THE EAST OF THE MOUNTAINS NEAR TO OR AFTER
06Z...AS HIGH PRESSURE BEGINS TO BUILD IN FROM THE NORTH. SHOULD BE
ENOUGH OF A PRESSURE GRADIENT OVERNIGHT AS WELL AS CLOUD COVER
ACROSS MUCH OF THE AREA...TO PREVENT WIDESPREAD FOG FORMATION AS
SEEN IN RECENT NIGHTS...BUT SHELTERED RIVER VALLEYS WILL STILL BE
SUSCEPTIBLE TO FOG FORMATION...SUCH AS NEAR ELKINS.
HIGH PRESSURE TO THE NORTH CENTERED OVER THE GREAT LAKES WILL BE IN
CONTROL THURSDAY...KEEPING THE WEATHER RELATIVELY DRY...AND SLIGHTLY
COOLER THAN TODAY. HOWEVER...THERE WILL BE A SLIGHT CHANCE FOR
THUNDERSTORMS...MAINLY ALONG THE HIGHER TERRAIN...AS THE POSITION OF
THE SURFACE HIGH CREATES A SOUTHEASTERLY/EASTERLY UPSLOPE FLOW. THIS
COMBINED WITH DAYTIME HEATING MAY TRIGGER ISOLD CONVECTION OVER
HIGHER TERRAIN...WITH ANYTHING THAT DOES FORM EXPECTED TO DIE OFF
LATER THURSDAY WITH THE LOSS OF DAYTIME HEATING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AREA IS ON WESTERN FRINGES OF MID ATLANTIC STACKED LOW PRESSURE
SYSTEM SUN NT AND MON...BEFORE THAT SYSTEM IS KICKED E BY A NEW
UPSTREAM NORTHERN STREAM S/W TROUGH. SOME OF THE ENERGY FROM THE
NORTHERN STREAM TROUGH GETS FED INTO THE SOUTHERN STREAM...THUS
HELPING TO KICK THE MID ATLANTIC LOW OUT. MAINTAINED THE IDEA OF
CHANCE THUNDERSTORMS MAINLY IN THE MOUNTAINS. A SPOKE OF ENERGY
ROTATING AROUND THE N SIDE OF THE MID ATLANTIC LOW DAMPENS THE
DIURNAL CYCLE AS IT MOVES INTO THE NORTHERN MOUNTAINS MON MORNING.
THE NEW S/W APPROACHES LATE MON AND MOVES ACROSS MON NT THROUGH
TUE. THE THUNDERSTORM CHANCE SHOULD INCREASE FROM THE W LATE MON
GIVEN SFC LOW PRESSURE AND ASSOCIATED CONVERGENCE THERE...THE
APPROACH OF THE UPPER LEVEL SYSTEM...AND THE INSTABILITY AXIS
LOCATED ALONG THE SFC TROUGH. NAM12 SUGGESTS CAPE TO 2500 J / KG
AND LIX TO -6 AND ABOUT A BUCK AND A THIRD PW. FLOW IS ON THE ORDER
OF TEN KNOTS SO SLOW MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW
VALUES WIND UP HIGHER THAN THAT.
CARRIED HIGH CHANCE SHOWERS AND THUNDERSTORMS WELL INTO TUE NT...AS
IT IS HARD TO DETERMINE MOVEMENT OF CLUSTERS WITHIN THE SLOW MOVING
PARENT SYSTEM. MODEL DIFFERENCES REMAIN AS TO WHETHER THE NEW
SYSTEM SIMPLY TAKES OVER AS A NEW MID ATLANTIC UPPER LEVEL LOW.
THIS FACTORS INTO HOW QUICKLY PRECIPITATION ENDS FROM THE W TUE NT.
CONTINUE WITH A MIDDLE GROUND TO SLOW STANCE HERE...WITH THE GFS
MOST PROGRESSIVE.
BLENDED IN THE MET FOR TEMPERATURES EARLY ON AND THEN THE BIAS
CORRECTED MAV FOR HIGHS TUE...TO BETTER REFLECT TEMPERATURE TRENDS
IN RELATION TO THE UPPER LEVEL SYSTEM THAT ARRIVES FROM THE W. THE
COOLEST PERIOD LOOKS TO BE TUE THROUGH TUE NT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLNS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS ACROSS THE REGION DURING THE
PERIOD...HOWEVER...PATCHY RIVER VALLEY FOG/HAZE IS EXPECTED ONCE
AGAIN AFTER 06Z...CREATING BRIEF LOW VFR/MVFR CONDITIONS. ANY FOG
THAT DOES DEVELOP WILL BURN OFF AFTER 13Z...WITH A RETURN OF VFR
CONDITIONS AREA WIDE WITH LIGHT SURFACE WINDS. A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS IS POSSIBLE OVER THE MOUNTAINS OF WEST
VIRGINIA TOWARDS THE END OF THE PERIOD...WITH BRIEF MVFR
CONDITIONS POSSIBLE IN VICINITY OF SHOWERS/STORMS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY...AND EVEN WHETHER IT OCCURS AT CERTAIN SITES OR NOT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SUNDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...SL
000
FXUS61 KCLE 191952
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
352 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH TOMORROW AND THEN MOVE OFF THE EAST COAST ON MONDAY. A
COLD FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM
THE WEST WHILE LOW PRESSURE MOVES NORTH ALONG THE MID ATLANTIC
COAST MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE
EAST ON TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE OVER THE AREA TONIGHT WILL ALLOW FOR MAINLY CLEAR
SKIES AND QUIET CONDITIONS. SOME CIRRUS CLOUDS MOVING NORTHWARD
INTO EASTERN AREAS...BUT NOT ENOUGH COVERAGE IN GRIDS TO MENTION
PARTLY CLOUDY. MAINLY MOSTLY CLEAR SKIES TONIGHT. USED A BLEND OF
MET AND MAV TEMPS...WITH LOWER 50S IN THE GOOD RADIATING SPOTS.
WOULD NOT BE SURPRISED TO SEE UPPER 40S ACROSS THE INTERIOR OF NW
PA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAIN ACROSS THE AREA ON SUNDAY WITH TEMPS SIMILAR
OR A BIT WARMER...WITH A LAKE BREEZE LIKELY IN THE AFTERNOON.
THERE MAY BE SOME CIRRUS CLOUDS ACROSS THE EAST AGAIN BUT NOT MUCH
IMPACT ON THE MOSTLY SUNNY SKIES. LOWS WARMER SUNDAY NIGHT AS A
COLD FRONT APPROACHES FROM THE WEST.
MODELS SHOWING A COLD FRONT APPROACHING THE AREA MONDAY. FOR NOW
WENT WITH MAINLY DRY CONDITIONS IN THE MORNING WITH INCREASING
POPS ACROSS THE WEST IN THE AFTERNOON. MEANWHILE...MOISTURE
SPREADING WESTWARD FROM LOW PRESSURE ALONG THE EAST COAST. WHILE
THERE IS STILL SOME DISCREPANCIES AS TO HOW FAR PRECIP WILL GET
ACROSS THE APPALACHIANS THERE WILL AT LEAST BE INCREASING CLOUDS.
MENTION LOW CHC POPS ACROSS THE FAR EAST INCLUDING NW PA IN THE
AFTERNOON...WITH CHC POPS ALSO ACROSS THE WEST WITH THE COLD FRONT
APPROACHING. CENTRAL LOCATIONS FROM CLE-MFD ONLY HAVE SLGT UNTIL
MONDAY NIGHT.
BETWEEN THE FRONT AND ANY POSSIBLE SHOWERS FROM MOISTURE BY THE
EAST COAST LOW LOOKS LIKE THERE WILL BE AT LEAST A CHANCE FOR
SHRA/TS MONDAY NIGHT ACROSS THE ENTIRE AREA. GIVEN INCREASING
DEWPOINTS ACROSS THE AREA KEEP LOWS AROUND 60 FOR MUCH OF THE
AREA.
MODELS SHOWING AN UPPER TROUGH OVER THE OHIO VALLEY SOUTH OF THE
AREA THROUGH TUESDAY...SO GIVEN SOME REMAINING INSTABILITY ACROSS
THE AREA CHC POPS FOR SHRA/THUNDERSTORMS CONTINUE. GFS A BIT
QUICKER THAN 12Z ECMWF IN BRINGING IN HIGH PRESSURE THROUGH
TUESDAY NIGHT. ALLOWED WESTERN AREAS TO DRY OUT TUESDAY NIGHT
WHILE LOWERING POPS TO SLGT CHC/LOW CHC ACROSS THE FAR EAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS NOT IN COMPLETE AGREEMENT. THE GFS HAS AN UPPER RIDGE
ACROSS THE REGION WEDNESDAY WHILE THE 12Z ECMWF HAS AN UPPER LOW
OVER THE TENNESSEE VALLEY THAT WILL VERY SLOWLY MOVE SOUTHEAST
THROUGH THURSDAY NIGHT. IF THE ECMWF IS CORRECT THIS COULD MEAN A
THREAT OF PRECIPITATION WILL HANG ON OVER NORTHEAST OHIO AND
NORTHWEST PA INTO THURSDAY NIGHT. BECAUSE OF THE UNCERTAINTY KEPT
LOW CHANCE POPS INTO WEDNESDAY FOR THE EASTERN PORTION OF THE
FORECAST AREA AND THEN DRY AFTER THAT. THIS WILL HAVE TO BE
MONITORED.
BY THE END OF THE WEEK A RIDGE ALOFT WILL BE OVER THE AREA WITH
PLENTY OF WARM TEMPERATURES AND HIGHS NEAR 90. OTHERWISE WENT CLOSE
TO HPC FOR TEMPERATURES.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VFR FOR THE TAF PERIOD. HIGH PRESSURE RIDGE ACROSS THE FORECAST
AREA WILL PERSIST INTO SUNDAY. A LAKE BREEZE HAS DEVELOPED AND
WILL CONTINUE THRU SUNSET. SOME THIN CIRRUS WILL SPREAD FROM SOUTH TO
NORTH INTO TONIGHT BECAUSE OF AN UPPER LOW OVER THE SOUTHEAST STATES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON AND POSSIBLY CONTINUING THROUGH WEDNESDAY NIGHT.
&&
.MARINE...
NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WORK WEEK...HOWEVER...FORECASTS WILL HAVE TO BE
MONITORED BECAUSE OF MODEL UNCERTAINTY.
THE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY WEAKEN ON
SUNDAY. A WEAK COLD FRONT WILL MOVE ACROSS THE LAKE MONDAY INTO
MONDAY NIGHT. THE WINDS WILL BE ONSHORE BEHIND THE FRONT BUT IT
LOOKS LIKE THEY WILL BE WEAK ENOUGH THAT A SMALL CRAFT ADVISORY MAY
NOT BE NEEDED. HIGH PRESSURE BUILDS BACK IN BY LATE TUESDAY AND THEN
THE RIDGE MOVES EAST WEDNESDAY AND THE AREA GETS INTO A SOUTHWEST OR
SOUTH FLOW. THE NEXT FRONTAL SYSTEM MOVES TOWARD THE LAKE FOR THE
EARLY PART OF NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
000
FXUS61 KILN 191948
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
348 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE WEEKEND. A SLOW
MOVING FRONT WILL MOVE EAST INTO THE OHIO VALLEY ON
MONDAY...PROVIDING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY. DRY WEATHER AND WARMING TEMPERATURES WILL BE IN PLACE FOR
THE REST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SURFACE MOISTURE HAS DECREASED SOMEWHAT DURING THE DAY TODAY...AS
TEMPERATURES HAVE RISEN WELL INTO THE 80S UNDER HIGH PRESSURE AND
CLEAR CONDITIONS. THE ATMOSPHERE OVER THE CWA IS CAPPED...LIMITING
CLOUD DEVELOPMENT TO FLAT...HIGH BASED CUMULUS. IN OVERALL WEAK
FLOW...MODEL AGREEMENT THROUGH THE NEAR TERM IS STRONG OVER THE
MIDDLE OHIO VALLEY. MIN TEMPERATURES WERE RAISED SLIGHTLY IN THE
WEST...AS MOISTURE WILL SLOWLY BEGIN TO INCREASE OVERNIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS WIND FLOW TURNS MORE SOUTHERLY ON SUNDAY...MOISTURE WILL
CONTINUE TO INCREASE SLIGHTLY OVER THE REGION. WITH LESS CAPPING
AND HIGHER DEWPOINTS...SOME INSTABILITY WILL BE
PRESENT...ESPECIALLY IN THE SOUTHWEST. HOWEVER...HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE OVERALL PATTERN...WITH NO SIGNS OF
ANY TRIGGER FOR CONVECTION. THIS MAY BE A SITUATION WHERE A VERY
ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE DURING THE DIURNAL
HEATING CYCLE...AND MAINLY IN THE WEST AND SOUTHWEST PARTS OF THE
CWA. WOULD BEST CATEGORIZE THIS AS A 10-PERCENT POP FOR NOW.
AS A POTENTIAL TROPICAL SYSTEM MOVES NEAR THE COAST...A SLOW
MOVING COLD FRONT ON A SSW-TO-NNE ORIENTATION WILL MOVE INTO THE
OHIO VALLEY. WHILE THIS MAY PRESENT SOME FORECAST DIFFICULTY AS
THE FEATURES INTERACT OVER THE APPALACHIANS...AT THIS TIME THERE
IS HIGH CONFIDENCE THAT THE PROGRESS OF THE FRONT WILL BE LARGELY
UNIMPEDED (THOUGH SLOW) FOR THE ILN FORECAST AREA.
INSTABILITY WILL BE PRESENT AHEAD OF THE FRONT AND WEAK SURFACE
LOW...GENERALLY AROUND 1000 J/KG OF MLCAPE PER GFS AND NAM
DEPICTIONS. THE SLOW MOTION OF THE FRONT AND WEAK WIND FIELDS SEEM
TO PRECLUDE SEVERE WEATHER THREATS...THOUGH THE SLOW MOTION MAY
SUPPORT SOME LOCALLY HEAVY RAINFALL.
MIN TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE
OF GUIDANCE...ESPECIALLY SUNDAY NIGHT AND MONDAY NIGHT. THE RAW NAM
TEMPERATURES CAPTURE THE IMPACTS OF THE FRONTAL SYSTEM AND THE
MOIST AIR MASS ASSOCIATED WITH IT. DEPENDING ON THE RAINFALL
PATTERNS...HIGHS ON MONDAY IN THE WESTERN HALF OF THE CWA MAY COME
EARLIER IN THE DAY THAN NORMAL. THERE IS GOOD AGREEMENT IN THE
MODELS ON MONDAY BEING AROUND 5 DEGREES COOLER THAN
SUNDAY IN THE WEST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
WILL SIDE WITH AN HPC SOLUTION FOR THE EXTENDED FORECAST. THIS
SOLUTION TAKES A BLEND OF THE GFS AND ECMWF IN REGARDS TO UPR LVL
TROUGH POSITION/MOVEMENT FOR THE TUESDAY THROUGH THURSDAY TIME FRAME.
FORECAST WILL ALLOW UPR LVL TROUGH TO GRADUALLY MOVE OFF TO THE EAST
AND CLOSE OFF. CONFIDENCE IS NOT THE HIGHEST WITH THIS SOLUTION AS
MODELS TYPICALLY STRUGGLE WITH HOW UPR TROUGHS CLOSE OFF AND
PROGRESS THEREAFTER. SO IT WILL BEHOOVE ONE TO MONITOR LATER
FORECASTS. MODELS SEEM TO AGREE THAT BY WEEKS END AN UPR LVL RIDGE
WILL BUILD ACRS THE OHIO VALLEY. AS FOR TEMPERATURES...THEY WILL
START OFF NEAR NORMAL TUESDAY AND WEDNESDAY...THEN GRADUALLY WARM TO
ABOVE NORMAL READINGS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
FEW CU OVER SOUTHWEST CWA THIS AFTERNOON WILL APPEAR AGAIN
TOMORROW. OTHERWISE SOME THIN CI WILL BE THE ONLY CLOUD COVER
EXPECTED IN THE NEXT 24-30 HOUR PERIOD. WIND WILL BE LIGHT FROM
THE EAST-SOUTHEAST AND PROBABLY GO CALM OVERNIGHT FOR MOST OF THE
OHIO VALLEY. KEPT A SINGLE LINE TAF AT KDAY AND KILN AS THE FLOW
FROM GUIDANCE NEVER BECAME ERRATIC AND MAINTAINED A 100-120
DIRECTION.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...FRANKS
000
FXUS61 KPBZ 191942
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
342 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH SUNDAY/...
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE
EXTENDING FROM THE THE OHIO VALLEY INTO NEW ENGLAND WITH ITS
ASSOCIATED WEAK ANTI-CYCLONIC FLOW CENTERED ACROSS THE OHIO
VALLEY. MEANWHILE, A CLOSED LOW IS LOCATED OFF THE CAROLINA COAST.
AT THE SURFACE, A BROAD AREA OF HIGH PRESSURE IS CENTERED ACROSS
THE NORTHEAST, EXTENDING SOUTHWESTWARD INTO THE REGION.
THE RIDGE WILL SHIFT FURTHER NORTHEAST TONIGHT AND TOMORROW,
ALLOWING FOR DRY WEATHER TO CONTINUE WITH UNSEASONABLY WARM
HIGH TEMPS. SKIES WILL BE MOSTLY CLEAR THROUGH THIS
PERIOD, ASIDE FROM SOME HIGH CIRRUS SPILLING INTO THE AREA AHEAD
OF THE LOW TO THE SOUTHEAST. DESPITE TEMPS IN THE LOW TO MID 80S
FOR HIGHS, DRY AIR IN PLACE ALONG WITH NEAR CALM WINDS AND MOSTLY
CLEAR SKIES OVERNIGHT WILL ALLOW FOR ANOTHER NIGHT OF DECENT
RADIATIONAL COOLING. THUS, LOWS ARE A MAV/MET BLEND, DROPPING TO
NEAR NORMAL SEASONAL VALUES, IN THE LOW TO MID 50S ACROSS THE
AREA. THE GFS INDICATES 850 TEMPS AROUND 15C TOMORROW. THIS WILL
CONTRIBUTE TO YET ANOTHER DAY WITH HIGHS 10-15 DEGREES ABOVE
NORMAL, RANGING FROM THE MID 80S ACROSS THE LOWLANDS TO THE MID
70S ACROSS THE EASTERN RIDGES.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
GFS/ECMWF INDICATE THE RIDGE AXIS BECOMING PINCHED OFF SUNDAY NIGHT
INTO MONDAY AS THE UPPER LOW MOVES INTO VIRGINIA AND A TROUGH MOVES
INTO THE UPPER MIDWEST. THE CLOSED LOW WILL SERVE TO DRAW MOISTURE
INTO THE AREA FROM THE ATLANTIC. WITH THIS IN MIND, THE CHANCE OF
SHOWERS BEGINS SOUTHEAST OF PITTSBURGH ON MONDAY MORNING. IN
ASSOCIATION WITH THE TROUGH, A FRONTAL BOUNDARY WILL CROSS THE OHIO
VALLEY ON MONDAY AFTERNOON. INCREASING MOISTURE AND INSTABILITY
AHEAD OF THIS FEATURE WILL LEAD TO THE CHANCE OF SHOWERS AND
THUNDERSTORMS MONDAY AFTERNOON THROUGH THE EVENING. INCREASED
CLOUD COVERAGE AND COOLER TEMPS ALOFT ASSOCIATED WITH THE LOW
APPROACHING FROM THE SOUTHEAST WILL ALLOW FOR A SLIGHT COOLER DAY
ON MONDAY, WITH HIGH TEMPS AT 5 TO 10 DEGREES ABOVE NORMAL,
RANGING FROM THE LOWER 80S ACROSS EASTERN OHIO TO NEAR 70 ACROSS
THE EASTERN RIDGES.
SOME MODEL UNCERTAINTY ENTERS THE FORECAST IN REGARDS TO THE TROUGH
MOVING INTO THE AREA FROM THE UPPER MIDWEST. ECMWF/NAM SOLUTIONS
MERGE THE UPPER LOW TO THE SOUTHEAST WITH THIS FEATURE INTO A MORE
AMPLIFIED TROUGH ACROSS THE AREA. MEANWHILE, THE GFS MOVES THE UPPER
LOW UP THE EAST COAST AND BRINGS A WEAKER TROUGH ACROSS THE AREA. WITH
THIS UNCERTAINTY IN MIND AND THE SLOW PASSAGE OF A FRONTAL
BOUNDARY, FORECAST IS A BLEND OF THE SOLUTIONS, CONTINUING A
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY.
WITH INCREASED CLOUD COVERAGE WITH SHOWERS AND THUNDERSTORMS,
HIGHS ON TUESDAY WILL BE SLIGHTLY COOLER IN COMPARISON TO THE
WEEKEND AND MONDAY, ALTHOUGH STILL AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR AND WINDS BELOW 10 KTS
FOR NEXT 24 HOURS. THE ONLY CLOUDS THAT ARE EXPECTED WILL BE WITH
BLOWOFF FROM POSSIBLE TROPICAL SYSTEM OFF CAROLINAS.
.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY. CONVECTION WILL ALSO INCREASE FROM THE EAST. SLOW
MOVING FRONT WILL BRING A CONTINUED CHANCE FOR SHOWERS AND
THUNDERSTORMS THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT
EAST OF THE AREA BY WEDNESDAY NIGHT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KPBZ 191759
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
159 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH SUNDAY/...
18Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED WITH MINOR
CHANGES TO THE GOING FORECAST TO ADJUST SKY GRIDS AS THIN CIRRUS
CONTINUES TO FILTER INTO THE AREA WELL AHEAD OF A LOW CENTER OFF THE
CAROLINA COAST.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE
EXTENDING FROM THE THE OHIO VALLEY INTO NEW ENGLAND WITH ITS
ASSOCIATED WEAK ANTI-CYCLONIC FLOW CENTERED ACROSS THE OHIO
VALLEY. MEANWHILE, A CLOSED LOW IS LOCATED OFF THE CAROLINA COAST.
AT THE SURFACE, A BROAD AREA OF HIGH PRESSURE IS CENTERED ACROSS
THE NORTHEAST, EXTENDING SOUTHWESTWARD INTO THE REGION.
THE RIDGE WILL SHIFT FURTHER NORTHEAST TONIGHT AND TOMORROW,
ALLOWING FOR DRY AND UNSEASONABLY WARM WEATHER TO CONTINUE. SKIES
WILL BE MOSTLY CLEAR THROUGH THIS PERIOD, ASIDE FROM SOME HIGH
CIRRUS SPILLING INTO THE AREA AHEAD OF THE LOW TO THE SOUTHEAST.
DESPITE TEMPS IN THE LOW TO MID 80S FOR HIGHS, DRY AIR IN PLACE
ALONG WITH NEAR CALM WINDS AND MOSTLY CLEAR SKIES OVERNIGHT WILL
ALLOW FOR ANOTHER NIGHT OF DECENT RADIATIONAL COOLING. THUS, LOWS
ARE A MAV/MET BLEND, DROPPING TO NEAR NORMAL SEASONAL VALUES, IN THE
LOW TO MID 50S ACROSS THE AREA. THE GFS INDICATES 850 TEMPS AROUND
15C TOMORROW. THIS WILL CONTRIBUTE TO YET ANOTHER DAY WITH HIGHS 10-15
DEGREES ABOVE NORMAL, RANGING FROM THE MID 80S ACROSS THE LOWLANDS
TO THE MID 70S ACROSS THE EASTERN RIDGES.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
MODELS CONTINUE TO STRUGGLE WITH THE INTERACTION OF THE CUTOFF LOW
OVER THE SOUTHEAST THROUGH AND THE TROUGH ACROSS THE UPPER
MIDWEST. AT THIS POINT...THE 500HPA RIDGE SHOULD BEGIN TO PINCH
OFF SUNDAY NIGHT AND AS IT TRANSFERS TO THE COAST THE UPSTREAM
TROUGH ACTUALLY HELPS TO BRING THE CUTOFF LOW FURTHER WEST.
THE ECMWF/GFS CONTINUE TO BE FAVORED THROUGH THIS TIME PERIOD AS
THE NAM KEEPS THE LOW SLIGHTLY FARTHER SOUTH. GRADUALLY INCREASE
PRECIP CHANCES FROM BOTH THE EAST AND WEST MONDAY AS WE ARE
SQUEEZED BETWEEN THE COLD FRONT AND THE CUTOFF LOW AND MAINTAIN
THOSE CHANCES THROUGH TUESDAY.
TEMPERATURES SHOULD CONTINUE TO REMAIN 10 DEGREES ABOVE NORMAL
SUNDAY AND 5-10 DEGREES ABOVE NORMAL MONDAY DESPITE INCREASING
CLOUD COVER AND PRECIPITATION CHANCES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
MODELS CONTINUE TO DISAGREE SOMEWHAT WITH REGARD TO TIMING OF THE
FRONT APPROACHING FROM THE WEST AND ON THE EXTENT OF
RETROGRESSION OF EAST COAST LOW EARLY NEXT WEEK.
STAYED CLOSE TO HPC GUIDANCE WHICH STILL LEANS TOWARD FASTER GFS
TIMING WITH THE FRONT AND PUSHES THE MAIN AREA OF PRECIPITATION
EAST OF THE REGION BY WEDNESDAY NIGHT.
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY DRY WEATHER FOR
THURSDAY INTO FRIDAY FOR MUCH OF THE FORECAST AREA. MOIST SOUTHEAST
FLOW FROM THE ATLANTIC DEPICTED BY THE ECMWF COULD MAINTAIN
SCATTERED PRECIPITATION OVER THE RIDGES ON THURSDAY NIGHT AND
FRIDAY.
TEMPERATURES ARE FORECAST TO RANGE FROM 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS AND LIGHT EAST WINDS WILL PREVAIL THROUGH THE TAF
PERIOD AS A SURFACE RIDGE HOLDS ALONG THE APPALACHIANS.
.OUTLOOK...SUNDAY THROUGH WEDNESDAY...
THE SURFACE RIDGE WILL MAINTAIN VFR WEATHER THROUGH SUNDAY NIGHT.
A FRONT WILL APPROACH FROM THE WEST LATE MONDAY WHILE A LOW
PRESSURE SYSTEM MOVES INLAND FROM THE CAROLINA COAST. MOISTURE
WILL INCREASE ACROSS THE REGION BY EARLY MONDAY ALONG WITH THE
POTENTIAL FOR RESTRICTIONS IN SHOWERS AND THUNDERSTORMS. SCATTERED
PRECIPITATION SHOULD PERSIST THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 191753
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
153 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE THROUGH WEEKEND...ALTHOUGH SOME MOISTURE MAY
INTRUDE FROM THE EAST TOWARD THE END OF THE WEEKEND. SYSTEMS
PROVIDE CHANCES OF SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
RELATIVELY QUIET WEATHER EXPECTED TO CONTINUE IN THE SHORT TERM.
KEPT THE SLIGHT CHANCE FOR SHOWERS IN THE CENTRAL MOUNTAINS THIS
AFTERNOON AS NEAR TERM LOCAL MODELS CONTINUE TO INDICATE THE
POSSIBILITY FOR ELEVATED HEAT SOURCE SHOWERS/THUNDER DEVELOPING
THIS AFTERNOON. OTHERWISE...MAINLY JUST SOME SCATTERED CU THIS
AFTERNOON IN THE DAYTIME HEAT...DISSIPATING WITH THE LOSS OF
HEATING THIS EVENING...AND SCATTERED CIRRUS OVER THE AREA FROM LOW
PRESSURE OFF THE COAST.
NEXT CHANCE FOR SHOWERS WILL OCCUR LATER IN THE DAY ON
SUNDAY...INTO SUNDAY NIGHT...MAINLY EAST...AS MOISTURE FROM THE LOW OFF
THE COAST IS ABLE TO ROTATE INTO THE REGION. BULK OF MOISTURE
LOOKS LIKE IT WILL HOLD OFF UNTIL AFTER THE NEAR TERM PERIOD...BUT
WITH INCREASED MOISTURE AND EASTERLY FLOW...WILL KEEP A MENTION
OVER THE HIGHER TERRAIN COUNTIES SUNDAY AFTERNOON AND EVENING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
MODELS IN MUCH BETTER AGREEMENT WITH THE GENERAL PATTERN FOR SUNDAY
THROUGH TUESDAY...ALTHOUGH SOME MINOR DIFFERENCES REMAIN. MODELS
SHOWING ENOUGH MOISTURE FROM THE ATLANTIC SYSTEM MAY SNEAK INTO THE
MOUNTAINS LATE SUNDAY TO PRODUCE A FEW THUNDERSTORMS. MOISTURE
CONTINUES PUSHING IN ON MONDAY...ALLOWING FOR CHANCES AREA WIDE.
MONDAY NIGHT AND TUESDAY A FRONT DROPPING IN FROM THE WEST BECOMES
THE MAIN FEATURE.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE 12Z GFS MAY BE TOO FAST MOVING MID LEVEL TROF EAST AND THROUGH
ON DAY 4/TUESDAY WITH MUCH DRIER AIR BY TUESDAY NIGHT. ON THE
OTHER HAND...THE 00Z ECMWF MAY BE ON THE SLOW SIDE...AS IT FORMS
ANOTHER MID LEVEL CUT OFF. WILL SIDE TOWARD A SLOWER SOLUTION
THOUGH...IN THIS WEAK SLUGGISH FLOW.
SO LEFT LOW CHANCE POPS FOR MANY COUNTIES FOR WEDNESDAY...PER HPC
MEDIUM RANGE GUIDANCE AND PER OUR PREVIOUS FCST. THE UNUSUAL MAY
PATTERN WILL LIKELY MIGRATE BACK TO AN EASTERLY FLOW ONCE AGAIN
DURING DAY 6 INTO DAY 7...AS MID LEVEL HEIGHTS BUILD TO OUR NORTH.
THIS SHOULD TRY TO WARM US UP AND SLOWLY DRY US OUT. YET...AT THIS
DISTANCE...RODE WITH HPC LOW CHANCE POPS ON FRIDAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS ACROSS THE REGION DURING THE
PERIOD...HOWEVER...PATCHY RIVER VALLEY FOG/HAZE IS EXPECTED ONCE
AGAIN AFTER 06Z...CREATING BRIEF LOW VFR/MVFR CONDITIONS. ANY FOG
THAT DOES DEVELOP WILL BURN OFF AFTER 13Z...WITH A RETURN OF VFR
CONDITIONS AREA WIDE WITH LIGHT SURFACE WINDS. A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS IS POSSIBLE OVER THE MOUNTAINS OF WEST
VIRGINIA TOWARDS THE END OF THE PERIOD...WITH BRIEF MVFR
CONDITIONS POSSIBLE IN VICINITY OF SHOWERS/STORMS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY...AND EVEN WHETHER IT OCCURS AT CERTAIN SITES OR NOT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY M M M M M M M M H H H H
HTS CONSISTENCY L M M M M M M M H H H H
BKW CONSISTENCY M M M M M M M M H H H H
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY M M M M M M M M H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 18Z SUNDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...SL
000
FXUS61 KCLE 191749
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
149 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE RIDGE ACROSS THE REGION. THE ONSHORE FLOW HAS
DEVELOPED. NOON TEMPERATURES ARE WARM AT INLAND LOCATIONS...RAISED
THE HIGHS BASED ON THAT. OTHERWISE NO SIGNIFICANT CLOUDS...JUST
SOME THIN CIRRUS OVER NORTHEAST OHIO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR FOR THE TAF PERIOD. HIGH PRESSURE RIDGE ACROSS THE FORECAST
AREA WILL PERSIST INTO SUNDAY. A LAKE BREEZE HAS DEVELOPED AND
WILL CONTINUE THRU SUNSET. SOME THIN CIRRUS WILL SPREAD FROM SOUTH TO
NORTH INTO TONIGHT BECAUSE OF AN UPPER LOW OVER THE SOUTHEAST STATES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON AND POSSIBLY CONTINUING THROUGH WEDNESDAY NIGHT.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...KIELTYKA
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KIELTYKA
MARINE...KOSARIK
000
FXUS61 KILN 191736
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
136 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION THROUGH
THE WEEKEND. A SLOW MOVING LOW PRESSURE SYSTEM WILL TRACK ACROSS
THE AREA EARLY NEXT WEEK BRINGING UNSETTLED CONDITIONS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
KEPT A WARMER THAN GUIDANCE FEEL WITH THE FORECAST TODAY AND HAVE
GENERALLY BEEN MAKING COSMETIC CHANGES TO THE TEMPERATURE/DEWPOINT
TRACES APPROACHING THE CURRENT TIME. SKY COVER IS MINIMAL AT BEST
OVER THE SOUTHWEST AND IN KY WITH FEW FAIR WX CU EXPECTED TO
DISSIPATE LATER IN THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
MOISTURE WILL GRADUALLY INCREASE IN SOUTHERLY FLOW BETWEEN HIGH
PRESSURE TO THE EAST AND AN APPROACHING LOW. THIS WILL RESULT IN
NIGHTTIME LOWS BEING SLIGHTLY WARMER EACH NIGHT. BUT HIGHS ON
SUNDAY SHOULD BE SIMILAR TO TODAYS READINGS WITH MAYBE JUST A BIT
MORE CLOUD COVER.
AS A TROUGH AND ASSOCIATED SURFACE LOW PUSH INTO THE REGION ON
MONDAY...SHOWERS AND THUNDERSTORMS WILL SPREAD INTO THE FORECAST
AREA. THE GREATEST CHANCE WILL BE IN THE WESTERN ZONES DURING THE
AFTERNOON. WIND FIELDS WILL BE VERY WEAK...SO CONVECTION SHOULD BE
DISORGANIZED. CLOUDS AND PRECIPITATION WILL HOLD DOWN TEMPERATURES
SLIGHTLY IN WESTERN COUNTIES. BUT READINGS SHOULD BE NEAR
PERSISTENCE IN THE EAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
SLOW MOVING UPPER TROUGH WILL EVENTUALLY CLOSE OFF INTO AN UPPER
LOW BY MID WEEK. AS A RESULT THERE WILL BE SCATTERED SHOWERS AND
THUNDERSTORMS MONDAY NIGHT INTO TUESDAY AND A NARROWED DIURNAL
RANGE IN TEMPERATURES. THE UPPER LOW WILL WOBBLE AROUND JUST
EAST OF THE AREA WEDNESDAY INTO THURSDAY BEFORE FINALLY PUSHING A
BIT FURTHER EAST. SO THE INFLUENCE OF THIS SYSTEM COULD STILL
RESULT IN SOME SHOWERS AND THUNDERSTORMS IN EASTERN SECTIONS
DURING THE MIDDLE OF THE WEEK. TEMPERATURES WILL SLOWLY REBOUND
DURING THIS TIME FRAME. THE AREA WILL DRY OUT LATE IT THE PERIOD
WITH MUCH WARMER TEMPERATURES AS AN UPPER RIDGE STARTS TO PUSH
INTO THE REGION.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FEW CU OVER SOUTHWEST CWA THIS AFTERNOON WILL APPEAR AGAIN
TOMORROW. OTHERWISE SOME THIN CI WILL BE THE ONLY CLOUD COVER
EXPECTED IN THE NEXT 24-30 HOUR PERIOD. WIND WILL BE LIGHT FROM
THE EAST-SOUTHEAST AND PROBABLY GO CALM OVERNIGHT FOR MOST OF THE
OHIO VALLEY. KEPT A SINGLE LINE TAF AT KDAY AND KILN AS THE FLOW
FROM GUIDANCE NEVER BECAME ERRATIC AND MAINTAINED A 100-120
DIRECTION.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...FRANKS
SHORT TERM...
LONG TERM...
AVIATION...FRANKS
000
FXUS61 KCLE 191630
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
1230 PM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE RIDGE ACROSS THE REGION. THE ONSHORE FLOW HAS
DEVELOPED. NOON TEMPERATURES ARE WARM AT INLAND LOCATIONS...RAISED
THE HIGHS BASED ON THAT. OTHERWISE NO SIGNIFICANT CLOUDS...JUST
SOME THIN CIRRUS OVER NORTHEAST OHIO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE TODAY WITH CLEAR SKIES. LAKE BREEZE
WIND SHIFTS WILL OCCUR AT KCLE AND KERI EARLY THIS AFTERNOON. WIND
SPEEDS WILL BE LESS THAN 10 KNOTS AT ALL SITES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON THROUGH WEDNESDAY.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...KIELTYKA
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KPBZ 191455
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1055 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE FOR DRY WEATHER WITH A WARMING TREND
CONTINUING THROUGH THE WEEKEND. THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL RETURN ON MONDAY AS MOISTURE FROM A LOW OFF THE
COAST MOVES INLAND AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO
SLIGHTLY INCREASE SKY GRIDS SOUTHEAST OF PITTSBURGH AS THIN CIRRUS
SPILLS INTO THE AREA FROM A LOW OFF THE CAROLINA COAST.
STRONG MID-LEVEL RIDGE WILL CONTINUE TO DOMINATE THE WEATHER
THROUGH THE NEAR AND SHORT TERM WHILE A CUTOFF LOW...BEST
DEPICTED BY CONVECTION OFF OF THE CAROLINAS...REMAINS NEARLY
STATIONARY THROUGH THE DAY TODAY. CLOUD COVER SHOULD BE MINIMAL
ASIDE FROM SOME HIGH CIRRUS ASSOCIATED WITH THE LOW THAT WILL
MOVE OVER THE NORTHERN WV/SOUTHERN PA COUNTIES INTO THE AFTERNOON.
CLEAR SKIES AND LIGHT MIXING WILL ALLOW FOR TEMPERATURES TO ONCE
AGAIN REBOUND TO ABOVE NORMAL VALUES TODAY. STRAYED ONLY A DEGREE
OR TWO FROM MOS GUIDANCE TEMPERATURES TODAY AND TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
MODELS CONTINUE TO STRUGGLE WITH THE CUTOFF LOW OVER THE SOUTHEAST
THROUGH MOST OF THIS PERIOD. WHILE THERE IS A GENERAL MODEL
CONSENSUS THAT SUNDAY SHOULD REMAIN DRY...ANY MORE FLUCTUATION OF
THE LOW NORTH OR WEST COULD ALLOW FOR SOME OF THE MOISTURE TO
REACH THE RIDGES. AT THIS POINT...THE 500HPA RIDGE SHOULD
MAINTAIN ITS HOLD OVER MUCH OF THE NORTHEAST THROUGH SUNDAY AND AS
IT TRANSFERS TO THE COAST THE UPSTREAM TROUGH ACTUALLY HELPS TO
BRING THE CUTOFF LOW FURTHER WEST.
THE ECMWF/GFS CONTINUE TO BE FAVORED THROUGH THIS TIME PERIOD AS
THE NAM KEEPS THE LOW SLIGHTLY FARTHER SOUTH. GRADUALLY INCREASE
PRECIP CHANCES FROM BOTH THE EAST AND WEST MONDAY AS WE ARE
SQUEEZED BETWEEN THE COLD FRONT AND THE CUTOFF LOW AND MAINTAIN
THOSE CHANCES THROUGH TUESDAY.
TEMPERATURES SHOULD CONTINUE TO REMAIN 10 DEGREES ABOVE NORMAL
SUNDAY AND 5-10 DEGREES ABOVE NORMAL MONDAY DESPITE INCREASING
CLOUD COVER AND PRECIPITATION CHANCES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
MODELS CONTINUE TO DISAGREE SOMEWHAT WITH REGARD TO TIMING OF THE
FRONT APPROACHING FROM THE WEST AND ON THE EXTENT OF
RETROGRESSION OF EAST COAST LOW EARLY NEXT WEEK.
STAYED CLOSE TO HPC GUIDANCE WHICH STILL LEANS TOWARD FASTER GFS
TIMING WITH THE FRONT AND PUSHES THE MAIN AREA OF PRECIPITATION
EAST OF THE REGION BY WEDNESDAY NIGHT.
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY DRY WEATHER FOR
THURSDAY INTO FRIDAY FOR MUCH OF THE FORECAST AREA. MOIST SOUTHEAST
FLOW FROM THE ATLANTIC DEPICTED BY THE ECMWF COULD MAINTAIN
SCATTERED PRECIPITATION OVER THE RIDGES ON THURSDAY NIGHT AND
FRIDAY.
TEMPERATURES ARE FORECAST TO RANGE FROM 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS AND LIGHT EAST WINDS WILL PREVAIL THROUGH THE TAF
PERIOD AS A SURFACE RIDGE HOLDS ALONG THE APPALACHIANS.
.OUTLOOK...SUNDAY THROUGH WEDNESDAY...
THE SURFACE RIDGE WILL MAINTAIN VFR WEATHER THROUGH SUNDAY NIGHT.
A FRONT WILL APPROACH FROM THE WEST LATE MONDAY WHILE A LOW
PRESSURE SYSTEM MOVES INLAND FROM THE CAROLINA COAST. MOISTURE
WILL INCREASE ACROSS THE REGION BY EARLY MONDAY ALONG WITH THE
POTENTIAL FOR RESTRICTIONS IN SHOWERS AND THUNDERSTORMS. SCATTERED
PRECIPITATION SHOULD PERSIST THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KRLX 191401
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1001 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE THROUGH WEEKEND...ALTHOUGH SOME MOISTURE MAY
INTRUDE FROM THE EAST TOWARD THE END OF THE WEEKEND. SYSTEMS
PROVIDE CHANCES OF SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE...NO MAJOR CHANGES NEEDED TO THE FORECAST.
PREVIOUS DISCUSSION BELOW...
QUIET IN THE NEAR TERM WX WISE. LOW PRESSURE WILL REMAIN NEARLY
STATIONARY JUST OFF THE CAROLINA COAST. LITTLE EFFECTS ACROSS THE
AREA OTHER THAN SOME CIRRUS WITH SOME FLAT CU POSSIBLE UNDERNEATH
IT. DONT SEE MUCH CHC FOR AFTN CONVECTION ACROSS THE MTNS TODAY
WITH FLOW TURNING MORE E TO ENE TDY AMID RATHER DRY AIR ARND H7.
SHOULD SEE A DEGREE OR TWO HIGHER THAN YESTERDAYS HIGHS...LOW TO
MID 80S WITH SOME 70S IN HIGHER ELEVATIONS.
AREAS OF CIRRUS TONIGHT...OTHERWISE JUST SOME LOCALIZED RVR VALLEY
FG/HZ LATE.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
MODELS IN MUCH BETTER AGREEMENT WITH THE GENERAL PATTERN FOR SUNDAY
THROUGH TUESDAY...ALTHOUGH SOME MINOR DIFFERENCES REMAIN. MODELS
SHOWING ENOUGH MOISTURE FROM THE ATLANTIC SYSTEM MAY SNEAK INTO THE
MOUNTAINS LATE SUNDAY TO PRODUCE A FEW THUNDERSTORMS. MOISTURE
CONTINUES PUSHING IN ON MONDAY...ALLOWING FOR CHANCES AREA WIDE.
MONDAY NIGHT AND TUESDAY A FRONT DROPPING IN FROM THE WEST BECOMES
THE MAIN FEATURE.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE 12Z GFS MAY BE TOO FAST MOVING MID LEVEL TROF EAST AND THROUGH
ON DAY 4/TUESDAY WITH MUCH DRIER AIR BY TUESDAY NIGHT. ON THE
OTHER HAND...THE 00Z ECMWF MAY BE ON THE SLOW SIDE...AS IT FORMS
ANOTHER MID LEVEL CUT OFF. WILL SIDE TOWARD A SLOWER SOLUTION
THOUGH...IN THIS WEAK SLUGGISH FLOW.
SO LEFT LOW CHANCE POPS FOR MANY COUNTIES FOR WEDNESDAY...PER HPC
MEDIUM RANGE GUIDANCE AND PER OUR PREVIOUS FCST. THE UNUSUAL MAY
PATTERN WILL LIKELY MIGRATE BACK TO AN EASTERLY FLOW ONCE AGAIN
DURING DAY 6 INTO DAY 7...AS MID LEVEL HEIGHTS BUILD TO OUR NORTH.
THIS SHOULD TRY TO WARM US UP AND SLOWLY DRY US OUT. YET...AT THIS
DISTANCE...RODE WITH HPC LOW CHANCE POPS ON FRIDAY.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
LIGHT FLOW SE SFC AND ALOFT BECOMING MORE E TO NE TDY AND TONIGHT.
RVR FG DISSIPATES BY 13Z FOR RETURN TO VFR AREAWIDE. CIRRUS
ASSOCIATED WITH LOW PRESSURE ALONG CAROLINA COAST WILL AFFECT AREA
TDY AND TONIGHT WITH SOME AFTN FLAT 4 TO 5 KFT BASE CU POSSIBLE AS
WELL.
MVFR FG AGAIN TONIGHT...MAINLY ALONG MAIN STEM RVRS AND TYGART
VALLEY AFTER 06Z WITH LOCALIZED IFR CONDITIONS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY...AND EVEN WHETHER IT OCCURS AT CERTAIN SITES OR NOT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY M M M M M M M M H H H H
HTS CONSISTENCY L M M M M M M M H H H H
BKW CONSISTENCY M M M M M M M M H H H H
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY M M M M M M M M H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 12Z SUNDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...SL/30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
000
FXUS61 KCLE 191344
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
944 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
JUST MADE SOME MINOR TWEAKS TO THE HIGHS FOR TODAY. PLENTY OF SUN.
AN ONSHORE FLOW WILL BE DEVELOPING WITH THE RIDGE JUST TO THE
NORTH OF OHIO AND NORTHWEST PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE TODAY WITH CLEAR SKIES. LAKE BREEZE
WIND SHIFTS WILL OCCUR AT KCLE AND KERI EARLY THIS AFTERNOON. WIND
SPEEDS WILL BE LESS THAN 10 KNOTS AT ALL SITES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON THROUGH WEDNESDAY.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...KIELTYKA
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KCLE 191147
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
747 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO CHANGE NEEDED FOR THE MORNING UPDATE. TEMPERATURES ARE STARTING
TO WARM UP WITH SUNRISE TOWARD HIGHS IN THE LOWER 80S THIS
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE TODAY WITH CLEAR SKIES. LAKE BREEZE
WIND SHIFTS WILL OCCUR AT KCLE AND KERI EARLY THIS AFTERNOON. WIND
SPEEDS WILL BE LESS THAN 10 KNOTS AT ALL SITES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED SHOWERS
AND THUNDERSTORMS AS WELL AS EARLY MORNING FOG/HAZE STARTING
MONDAY AFTERNOON THROUGH WEDNESDAY.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KPBZ 191127
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
727 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE FOR DRY WEATHER WITH A WARMING TREND
CONTINUING THROUGH THE WEEKEND. THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL RETURN ON MONDAY AS MOISTURE FROM A LOW OFF THE
COAST MOVES INLAND AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY MINOR CHANGES MADE WITH 730AM UPDATE. PREVIOUS DISCUSSION
FOLLOWS.
STRONG MID-LEVEL RIDGE WILL CONTINUE TO DOMINATE THE WEATHER
THROUGH THE NEAR AND SHORT TERM WHILE CUTOFF LOW...BEST DEPICTED BY
CONVECTION OFF OF THE CAROLINAS...REMAINS NEARLY STATIONARY
THROUGH THE DAY TODAY. CLOUD COVER SHOULD BE MINIMAL WITH CONTINUED
SUBSIDENCE ALTHOUGH SOME HIGH CIRRUS ASSOCIATED WITH THE LOW COULD
PASS OVER NORTHERN WV/SOUTHERN PA COUNTIES THIS MORNING/AFTERNOON.
CLEAR SKIES AND LIGHT MIXING WILL ALLOW FOR TEMPERATURES TO ONCE
AGAIN REBOUND TO ABOVE NORMAL VALUES TODAY. STRAYED ONLY A DEGREE
OR TWO FROM MOS GUIDANCE TEMPERATURES TODAY AND TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
MODELS CONTINUE TO STRUGGLE WITH THE CUTOFF LOW OVER THE SOUTHEAST
THROUGH MOST OF THIS PERIOD. WHILE THERE IS A GENERAL MODEL
CONSENSUS THAT SUNDAY SHOULD REMAIN DRY...ANY MORE FLUCTUATION OF
THE LOW NORTH OR WEST COULD ALLOW FOR SOME OF THE MOISTURE TO
REACH THE RIDGES. AT THIS POINT...THE 500HPA RIDGE SHOULD
MAINTAIN ITS HOLD OVER MUCH OF THE NORTHEAST THROUGH SUNDAY AND AS
IT TRANSFERS TO THE COAST THE UPSTREAM TROUGH ACTUALLY HELPS TO
BRING THE CUTOFF LOW FURTHER WEST.
THE ECMWF/GFS CONTINUE TO BE FAVORED THROUGH THIS TIME PERIOD AS
THE NAM KEEPS THE LOW SLIGHTLY FARTHER SOUTH. GRADUALLY INCREASE
PRECIP CHANCES FROM BOTH THE EAST AND WEST MONDAY AS WE ARE
SQUEEZED BETWEEN THE COLD FRONT AND THE CUTOFF LOW AND MAINTAIN
THOSE CHANCES THROUGH TUESDAY.
TEMPERATURES SHOULD CONTINUE TO REMAIN 10 DEGREES ABOVE NORMAL
SUNDAY AND 5-10 DEGREES ABOVE NORMAL MONDAY DESPITE INCREASING
CLOUD COVER AND PRECIPITATION CHANCES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
MODELS CONTINUE TO DISAGREE SOMEWHAT WITH REGARD TO TIMING OF THE
FRONT APPROACHING FROM THE WEST AND ON THE EXTENT OF
RETROGRESSION OF EAST COAST LOW EARLY NEXT WEEK.
STAYED CLOSE TO HPC GUIDANCE WHICH STILL LEANS TOWARD FASTER GFS
TIMING WITH THE FRONT AND PUSHES THE MAIN AREA OF PRECIPITATION
EAST OF THE REGION BY WEDNESDAY NIGHT.
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY DRY WEATHER FOR
THURSDAY INTO FRIDAY FOR MUCH OF THE FORECAST AREA. MOIST SOUTHEAST
FLOW FROM THE ATLANTIC DEPICTED BY THE ECMWF COULD MAINTAIN
SCATTERED PRECIPITATION OVER THE RIDGES ON THURSDAY NIGHT AND
FRIDAY.
TEMPERATURES ARE FORECAST TO RANGE FROM 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS AND LIGHT EAST WINDS WILL PREVAIL THROUGH THE TAF
PERIOD AS A SURFACE RIDGE HOLDS ALONG THE APPALACHIANS.
.OUTLOOK...SUNDAY THROUGH WEDNESDAY...
THE SURFACE RIDGE WILL MAINTAIN VFR WEATHER THROUGH SUNDAY NIGHT.
A FRONT WILL APPROACH FROM THE WEST LATE MONDAY WHILE A LOW
PRESSURE SYSTEM MOVES INLAND FROM THE CAROLINA COAST. MOISTURE
WILL INCREASE ACROSS THE REGION BY EARLY MONDAY ALONG WITH THE
POTENTIAL FOR RESTRICTIONS IN SHOWERS AND THUNDERSTORMS. SCATTERED
PRECIPITATION SHOULD PERSIST THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KCLE 191038
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
638 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO CHANGE NEEDED FOR THE MORNING UPDATE. TEMPERATURES ARE STARTING
TO WARM UP WITH SUNRISE TOWARD HIGHS IN THE LOWER 80S THIS
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE WITH ESSENTIALLY CLEAR SKIES (AND THE
OCCASIONAL PATCH OF CIRRUS). LAKE BREEZE WIND SHIFTS WILL OCCUR AT
KCLE AND KERI AND EVENTUALLY KTOL SATURDAY AFTERNOON. WIND SPEEDS
WILL BE LESS THAN 10 KNOTS AT ALL SITES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH ISOLATED/SCATTERED
SHOWERS/THUNDERSTORMS AND EARLY MORNING FOG/HAZE MONDAY THROUGH
WEDNESDAY.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
000
FXUS61 KRLX 191035
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
635 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE THROUGH WEEKEND...ALTHOUGH SOME MOISTURE MAY
INTRUDE FROM THE EAST TOWARD THE END OF THE WEEKEND. SYSTEMS
PROVIDE CHANCES OF SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
630AM UPDATE TO BEEF UP THE CIRRUS EAST OF I79 THIS MORNING.
PREVIOUS DISCUSSION BELOW...
QUIET IN THE NEAR TERM WX WISE. LOW PRESSURE WILL REMAIN NEARLY
STATIONARY JUST OFF THE CAROLINA COAST. LITTLE EFFECTS ACROSS THE
AREA OTHER THAN SOME CIRRUS WITH SOME FLAT CU POSSIBLE UNDERNEATH
IT. DONT SEE MUCH CHC FOR AFTN CONVECTION ACROSS THE MTNS TODAY
WITH FLOW TURNING MORE E TO ENE TDY AMID RATHER DRY AIR ARND H7.
SHOULD SEE A DEGREE OR TWO HIGHER THAN YESTERDAYS HIGHS...LOW TO
MID 80S WITH SOME 70S IN HIGHER ELEVATIONS.
AREAS OF CIRRUS TONIGHT...OTHERWISE JUST SOME LOCALIZED RVR VALLEY
FG/HZ LATE.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
MODELS IN MUCH BETTER AGREEMENT WITH THE GENERAL PATTERN FOR SUNDAY
THROUGH TUESDAY...ALTHOUGH SOME MINOR DIFFERENCES REMAIN. MODELS
SHOWING ENOUGH MOISTURE FROM THE ATLANTIC SYSTEM MAY SNEAK INTO THE
MOUNTAINS LATE SUNDAY TO PRODUCE A FEW THUNDERSTORMS. MOISTURE
CONTINUES PUSHING IN ON MONDAY...ALLOWING FOR CHANCES AREA WIDE.
MONDAY NIGHT AND TUESDAY A FRONT DROPPING IN FROM THE WEST BECOMES
THE MAIN FEATURE.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE 12Z GFS MAY BE TOO FAST MOVING MID LEVEL TROF EAST AND THROUGH
ON DAY 4/TUESDAY WITH MUCH DRIER AIR BY TUESDAY NIGHT. ON THE
OTHER HAND...THE 00Z ECMWF MAY BE ON THE SLOW SIDE...AS IT FORMS
ANOTHER MID LEVEL CUT OFF. WILL SIDE TOWARD A SLOWER SOLUTION
THOUGH...IN THIS WEAK SLUGGISH FLOW.
SO LEFT LOW CHANCE POPS FOR MANY COUNTIES FOR WEDNESDAY...PER HPC
MEDIUM RANGE GUIDANCE AND PER OUR PREVIOUS FCST. THE UNUSUAL MAY
PATTERN WILL LIKELY MIGRATE BACK TO AN EASTERLY FLOW ONCE AGAIN
DURING DAY 6 INTO DAY 7...AS MID LEVEL HEIGHTS BUILD TO OUR NORTH.
THIS SHOULD TRY TO WARM US UP AND SLOWLY DRY US OUT. YET...AT THIS
DISTANCE...RODE WITH HPC LOW CHANCE POPS ON FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LIGHT FLOW SE SFC AND ALOFT BECOMING MORE E TO NE TDY AND TONIGHT.
RVR FG DISSIPATES BY 13Z FOR RETURN TO VFR AREAWIDE. CIRRUS
ASSOCIATED WITH LOW PRESSURE ALONG CAROLINA COAST WILL AFFECT AREA
TDY AND TONIGHT WITH SOME AFTN FLAT 4 TO 5 KFT BASE CU POSSIBLE AS
WELL.
MVFR FG AGAIN TONIGHT...MAINLY ALONG MAIN STEM RVRS AND TYGART
VALLEY AFTER 06Z WITH LOCALIZED IFR CONDITIONS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY...AND EVEN WHETHER IT OCCURS AT CERTAIN SITES OR NOT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY M M M M M M M M H H H H
HTS CONSISTENCY M L L M M M M M H H H H
BKW CONSISTENCY M M M M M M M M H H H H
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY M M L M M M M M H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 12Z SUNDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
000
FXUS61 KILN 191035
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
635 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION THROUGH
THE WEEKEND. A SLOW MOVING LOW PRESSURE SYSTEM WILL TRACK ACROSS
THE AREA EARLY NEXT WEEK BRINGING UNSETTLED CONDITIONS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE AT THE SURFACE AND ALOFT WILL BE OVER THE REGION
THROUGH THE DAY. THERE MAY BE FEW CUMULUS AND SOME THIN CIRRUS...BUT
OVERALL PLENTY OF SUNSHINE. TEMPERATURES SHOULD BE SEVERAL DEGREES
WARMER THAN YESTERDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
MOISTURE WILL GRADUALLY INCREASE IN SOUTHERLY FLOW BETWEEN HIGH
PRESSURE TO THE EAST AND AN APPROACHING LOW. THIS WILL RESULT IN
NIGHTTIME LOWS BEING SLIGHTLY WARMER EACH NIGHT. BUT HIGHS ON
SUNDAY SHOULD BE SIMILAR TO TODAYS READINGS WITH MAYBE JUST A BIT
MORE CLOUD COVER.
AS A TROUGH AND ASSOCIATED SURFACE LOW PUSH INTO THE REGION ON
MONDAY...SHOWERS AND THUNDERSTORMS WILL SPREAD INTO THE FORECAST
AREA. THE GREATEST CHANCE WILL BE IN THE WESTERN ZONES DURING THE
AFTERNOON. WIND FIELDS WILL BE VERY WEAK...SO CONVECTION SHOULD BE
DISORGANIZED. CLOUDS AND PRECIPITATION WILL HOLD DOWN TEMPERATURES
SLIGHTLY IN WESTERN COUNTIES. BUT READINGS SHOULD BE NEAR
PERSISTENCE IN THE EAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
SLOW MOVING UPPER TROUGH WILL EVENTUALLY CLOSE OFF INTO AN UPPER
LOW BY MID WEEK. AS A RESULT THERE WILL BE SCATTERED SHOWERS AND
THUNDERSTORMS MONDAY NIGHT INTO TUESDAY AND A NARROWED DIURNAL
RANGE IN TEMPERATURES. THE UPPER LOW WILL WOBBLE AROUND JUST
EAST OF THE AREA WEDNESDAY INTO THURSDAY BEFORE FINALLY PUSHING A
BIT FURTHER EAST. SO THE INFLUENCE OF THIS SYSTEM COULD STILL
RESULT IN SOME SHOWERS AND THUNDERSTORMS IN EASTERN SECTIONS
DURING THE MIDDLE OF THE WEEK. TEMPERATURES WILL SLOWLY REBOUND
DURING THIS TIME FRAME. THE AREA WILL DRY OUT LATE IT THE PERIOD
WITH MUCH WARMER TEMPERATURES AS AN UPPER RIDGE STARTS TO PUSH
INTO THE REGION.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL CONTINUE TO KEEP DRY CONDITIONS ACROSS THE AREA
TAF SITES THROUGH THE TAF PERIOD. FOG HAS DEVELOPED AT KLUK THIS
MORNING. VSBYS WILL IMPROVE AS THE MORNING PROGRESSES AND VFR
CONDITIONS WILL RETURN. VFR CONDITIONS WILL START OUT THE TAF
PERIOD AT THE OTHER AREA TAF SITES. A FEW CU WILL DEVELOP FOR THE
AFTERNOON HOURS. WINDS WILL BE LESS THAN TEN KNOTS. FOG WILL DEVELOP
AGAIN TONIGHT AT KLUK. IN ADDITION...KCVG MAY SEE SOME FOG DEVELOPMENT
TONIGHT AS WELL.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
000
FXUS61 KPBZ 190901
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
501 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE FOR DRY WEATHER WITH A WARMING TREND
CONTINUING THROUGH THE WEEKEND. THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL RETURN ON MONDAY AS MOISTURE FROM A LOW OFF THE
COAST MOVES INLAND AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRONG MID-LEVEL RIDGE WILL CONTINUE TO DOMINATE THE WEATHER
THROUGH THE NEAR AND SHORT TERM WHILE CUTOFF LOW...BEST DEPICTED BY
CONVECTION OFF OF THE CAROLINAS...REMAINS NEARLY STATIONARY
THROUGH THE DAY TODAY. CLOUD COVER SHOULD BE MINIMAL WITH CONTINUED
SUBSIDENCE ALTHOUGH SOME HIGH CIRRUS ASSOCIATED WITH THE LOW COULD
PASS OVER NORTHERN WV/SOUTHERN PA COUNTIES THIS MORNING/AFTERNOON.
CLEAR SKIES AND LIGHT MIXING WILL ALLOW FOR TEMPERATURES TO ONCE
AGAIN REBOUND TO ABOVE NORMAL VALUES TODAY. STRAYED ONLY A DEGREE
OR TWO FROM MOS GUIDANCE TEMPERATURES TODAY AND TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
MODELS CONTINUE TO STRUGGLE WITH THE CUTOFF LOW OVER THE SOUTHEAST
THROUGH MOST OF THIS PERIOD. WHILE THERE IS A GENERAL MODEL
CONSENSUS THAT SUNDAY SHOULD REMAIN DRY...ANY MORE FLUCTUATION OF
THE LOW NORTH OR WEST COULD ALLOW FOR SOME OF THE MOISTURE TO
REACH THE RIDGES. AT THIS POINT...THE 500HPA RIDGE SHOULD
MAINTAIN ITS HOLD OVER MUCH OF THE NORTHEAST THROUGH SUNDAY AND AS
IT TRANSFERS TO THE COAST THE UPSTREAM TROUGH ACTUALLY HELPS TO
BRING THE CUTOFF LOW FURTHER WEST.
THE ECMWF/GFS CONTINUE TO BE FAVORED THROUGH THIS TIME PERIOD AS
THE NAM KEEPS THE LOW SLIGHTLY FARTHER SOUTH. GRADUALLY INCREASE
PRECIP CHANCES FROM BOTH THE EAST AND WEST MONDAY AS WE ARE
SQUEEZED BETWEEN THE COLD FRONT AND THE CUTOFF LOW AND MAINTAIN
THOSE CHANCES THROUGH TUESDAY.
TEMPERATURES SHOULD CONTINUE TO REMAIN 10 DEGREES ABOVE NORMAL
SUNDAY AND 5-10 DEGREES ABOVE NORMAL MONDAY DESPITE INCREASING
CLOUD COVER AND PRECIPITATION CHANCES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
MODELS CONTINUE TO DISAGREE SOMEWHAT WITH REGARD TO TIMING OF THE
FRONT APPROACHING FROM THE WEST AND ON THE EXTENT OF
RETROGRESSION OF EAST COAST LOW EARLY NEXT WEEK.
STAYED CLOSE TO HPC GUIDANCE WHICH STILL LEANS TOWARD FASTER GFS
TIMING WITH THE FRONT AND PUSHES THE MAIN AREA OF PRECIPITATION
EAST OF THE REGION BY WEDNESDAY NIGHT.
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY DRY WEATHER FOR
THURSDAY INTO FRIDAY FOR MUCH OF THE FORECAST AREA. MOIST SOUTHEAST
FLOW FROM THE ATLANTIC DEPICTED BY THE ECMWF COULD MAINTAIN
SCATTERED PRECIPITATION OVER THE RIDGES ON THURSDAY NIGHT AND
FRIDAY.
TEMPERATURES ARE FORECAST TO RANGE FROM 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS AND LIGHT EAST WINDS WILL PREVAIL THROUGH THE TAF
PERIOD AS A SURFACE RIDGE HOLDS ALONG THE APPALACHIANS.
.OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...
THE SURFACE RIDGE WILL MAINTAIN VFR WEATHER THROUGH SUNDAY NIGHT.
A FRONT WILL APPROACH FROM THE WEST LATE MONDAY WHILE A LOW
PRESSURE SYSTEM MOVES INLAND FROM THE CAROLINA COAST. MOISTURE WILL
INCREASE ACROSS THE REGION BY EARLY MONDAY ALONG WITH THE POTENTIAL
FOR RESTRICTIONS IN SHOWERS AND THUNDERSTORMS. SCATTERED
PRECIPITATION SHOULD PERSIST THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
000
FXUS61 KILN 190838
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
438 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS THE REGION THROUGH
THE WEEKEND. A SLOW MOVING LOW PRESSURE SYSTEM WILL TRACK ACROSS
THE AREA EARLY NEXT WEEK BRINGING UNSETTLED CONDITIONS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE AT THE SURFACE AND ALOFT WILL BE OVER THE REGION
THROUGH THE DAY. THERE MAY BE FEW CUMULUS AND SOME THIN CIRRUS...BUT
OVERALL PLENTY OF SUNSHINE. TEMPERATURES SHOULD BE SEVERAL DEGREES
WARMER THAN YESTERDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
MOISTURE WILL GRADUALLY INCREASE IN SOUTHERLY FLOW BETWEEN HIGH
PRESSURE TO THE EAST AND AN APPROACHING LOW. THIS WILL RESULT IN
NIGHTTIME LOWS BEING SLIGHTLY WARMER EACH NIGHT. BUT HIGHS ON
SUNDAY SHOULD BE SIMILAR TO TODAYS READINGS WITH MAYBE JUST A BIT
MORE CLOUD COVER.
AS A TROUGH AND ASSOCIATED SURFACE LOW PUSH INTO THE REGION ON
MONDAY...SHOWERS AND THUNDERSTORMS WILL SPREAD INTO THE FORECAST
AREA. THE GREATEST CHANCE WILL BE IN THE WESTERN ZONES DURING THE
AFTERNOON. WIND FIELDS WILL BE VERY WEAK...SO CONVECTION SHOULD BE
DISORGANIZED. CLOUDS AND PRECIPITATION WILL HOLD DOWN TEMPERATURES
SLIGHTLY IN WESTERN COUNTIES. BUT READINGS SHOULD BE NEAR
PERSISTENCE IN THE EAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
SLOW MOVING UPPER TROUGH WILL EVENTUALLY CLOSE OFF INTO AN UPPER
LOW BY MID WEEK. AS A RESULT THERE WILL BE SCATTERED SHOWERS AND
THUNDERSTORMS MONDAY NIGHT INTO TUESDAY AND A NARROWED DIURNAL
RANGE IN TEMPERATURES. THE UPPER LOW WILL WOBBLE AROUND JUST
EAST OF THE AREA WEDNESDAY INTO THURSDAY BEFORE FINALLY PUSHING A
BIT FURTHER EAST. SO THE INFLUENCE OF THIS SYSTEM COULD STILL
RESULT IN SOME SHOWERS AND THUNDERSTORMS IN EASTERN SECTIONS
DURING THE MIDDLE OF THE WEEK. TEMPERATURES WILL SLOWLY REBOUND
DURING THIS TIME FRAME. THE AREA WILL DRY OUT LATE IT THE PERIOD
WITH MUCH WARMER TEMPERATURES AS AN UPPER RIDGE STARTS TO PUSH
INTO THE REGION.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL KEEP DRY CONDITIONS ACROSS THE TAF SITES
THROUGH THE TAF PERIOD. VFR CONDITIONS WILL START OUT THE TAF
PERIOD HOWEVER SOME FOG WILL BE POSSIBLE AT KLUK...KCVG...AND KILN
OVERNIGHT. VFR CONDITIONS WILL RETURN TO THE TAF SITES DURING THE
DAY ON SATURDAY. CU WILL DEVELOP ACROSS THE AREA DURING MAINLY THE
AFTERNOON HOURS. WINDS WILL BE LESS THAN 10 KNOTS.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE MONDAY AND TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
000
FXUS61 KCLE 190755
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
355 AM EDT SAT MAY 19 2012
.SYNOPSIS...
HIGH PRESSURE OVER WESTERN NEW YORK WILL REMAIN NEARLY STATIONARY
THROUGH SUNDAY AND THEN MOVE OFF THE EAST COAST ON MONDAY. A COLD
FRONT AND WAVE OF LOW PRESSURE WILL APPROACH THE REGION FROM THE
WEST WHILE LOW PRESSURE MOVES NORTH INTO WESTERN PENNSYLVANIA ON
MONDAY. THE TWO SYSTEMS WILL MERGE MONDAY NIGHT AND MOVE EAST ON
TUESDAY. HIGH PRESSURE WILL BUILD SOUTHEAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE HIGH PRESSURE SYSTEM THAT CONTINUES TO BRING FAIR WEATHER TO THE
REGION WILL GRADUALLY BEGIN TO EXIT STAGE RIGHT OVER THE NEXT COUPLE
DAYS. THE HIGH WILL FINALLY BRING SOME APPRECIABLE WARM AIR TO THE
REGION TODAY AS SOUTHEAST FLOW DEVELOPS. VIRTUALLY CLEAR SKIES WILL
BE THE RULE THROUGH THE DAY AS STRONG SUBSIDENCE OCCURS UNDER THE
UPPER LEVEL RIDGE.
850 MB TEMPERATURES WARM TO 16 DEGREES THROUGH THE DAY. SURFACE
TEMPERATURES UPSTREAM WERE IN THE MIDDLE 80S. THIS WILL SUPPORT
TEMPERATURES ACROSS THE FORECAST AREA TO RUN ABOUT 10 DEGREES WARMER
THAN YESTERDAY IN THE WARM AIR ADVECTION PATTERN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
LIGHT WARM SOUTHEAST FLOW CONTINUES TONIGHT AND SHOULD HELP KEEP
TEMPERATURES WARMER THAN THIS MORNING. THE BEST WARMING WILL TAKE
PLACE IN THE EAST WHERE LOWS ARE EXPECTED TO BE IN THE MIDDLE TO
UPPER 50S. EXTREME EAST WILL SEE TEMPERATURES IN THE LOWER 50S AS
WINDS WILL BE LIGHTER IN THAT AREA. LIGHT TO CALM WINDS WILL SUPPORT
CONTINUED EXCELLENT RADIATIONAL COOLING TO TAKE PLACE. HENCE...THE
COOLER TEMPERATURES EAST.
SUNDAY AND SUNDAY NIGHT STILL LOOK LIKE WINNERS WITH WARM AIR
ADVECTION OVER THE REGION AND THE INFLUENCE OF HIGH PRESSURE STILL
IN PLACE. SUNSHINE WILL STILL BE ABUNDANT ON SUNDAY BUT GIVES WAY TO
CLOUDINESS SUNDAY NIGHT AND MONDAY.
THE BIG QUESTION IS THE TIMING OF THE RAIN ON MONDAY. SCENARIO IS
SOMEWHAT COMPLEX BECAUSE OF TWO WEATHER FEATURES MAKING A BEE LINE
FOR THE FORECAST AREA. FIRST...WE HAVE A COLD FRONT AND WEAK WAVE OF
LOW PRESSURE MOVING EAST TOWARD THE AREA ON MONDAY AND APPEARS THAT
IT WILL PUSH PRECIPITATION INTO TOLEDO AND FINDLAY. SECOND...WEAK
WAVE OF LOW PRESSURE SLIDES NORTH TOWARD THE EXTREME EASTERN
PORTIONS OF THE AREA. PROBLEM HERE IS HOW MUCH DOWNSLOPING OCCURS IN
ERIE TO PREVENT SHOWERS FROM DEVELOPING. IN THE MIDDLE...ANOTHER
FAIR WEATHER DAY IS EXPECTED BEING BETWEEN WEATHER SYSTEMS.
SO...WILL CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EXTREME WEST AND EXTREME EAST AND DROP MENTION OF SHOWERS IN THE
MIDDLE FOR MONDAY.
EVENTUALLY...THE WESTERN AND EASTERN WEATHER SYSTEMS MERGE AND
NEARLY STALL. THIS WILL KEEP A THREAT FOR SHOWERS AND THUNDERSTORMS
GOING THROUGH AT LEAST TUESDAY NIGHT.
I THINK TEMPERATURES WILL STILL BE ON THE WARM SIDE FOR MONDAY AS
PRECIPITATION TAKES A WHILE TO DEVELOP OVER THE AREA IN THE WEST AND
EAST. THERE IS THE POSSIBILITY THAT WE COULD SEE SOME
SUN...ESPECIALLY IN THE MIDDLE AND EASTERN PORTIONS TO HELP HEAT
THINGS UP FOR THE DAY. SHOOTING FOR LOWER 80S WEST HALF TO UPPER 70S
EAST HALF ON MONDAY.
SINCE THERE WILL BE CLOUDS AND A CHANCE OF RAIN THROUGH THE REST OF
THE PERIODS. THIS WILL DIMINISH TEMPERATURES BACK TO THE 70S. NIGHT
TIME LOWS WILL STILL BE MILD DUE TO CLOUD COVER. LOWS GENERALLY IN
THE UPPER 50S THROUGH THIS PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN GENERAL... ALL OF THE MODELS AGREE THAT AN IMPRESSIVE RIDGE WILL
BUILD ACROSS THE PLAINS AND EASTERN CANADA THROUGH THE EXTENDED
PORTION OF THE FORECAST. THE QUESTION IS... HOW FAST DOES THE UPPER
LOW/TROUGH EXIT OFF THE EAST COAST? THE GFS IS A BIT FASTER THAN THE
ECMWF AND WE WILL STICK WITH CONTINUITY WITH A SMALL CHANCE OF
SHOWER/STORMS LINGERING ON WEDNESDAY... THEN DRY WITH A WARMING
TREND. THERE WILL PROBABLY BE SOME LINGERING CLOUDS ON THURSDAY...
PERHAPS EVEN INTO FRIDAY... WITH CUMULUS LIKELY EACH DAY. WE SHOULD
SEE SOME REAL SUMMER-LIKE WEATHER BY THE END OF NEXT WEEK WITH HIGHS
WELL INTO THE 80S. WE COULD SEE THE FIRST 90F NEXT WEEKEND.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE WITH ESSENTIALLY CLEAR SKIES (AND THE
OCCASIONAL PATCH OF CIRRUS). LAKE BREEZE WIND SHIFTS WILL OCCUR AT
KCLE AND KERI AND EVENTUALLY KTOL SATURDAY AFTERNOON. WIND SPEEDS
WILL BE LESS THAN 10 KNOTS AT ALL SITES.
.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH ISOLATED/SCATTERED
SHOWERS/THUNDERSTORMS AND EARLY MORNING FOG/HAZE MONDAY THROUGH
WEDNESDAY.
&&
.MARINE...
WITH HIGH PRESSURE OVERHEAD... THE LAKE WILL BE QUIET THIS
WEEKEND. WIND SPEED AND DIRECTION WILL BE DICTATED MOSTLY BY LOCAL
ONSHORE/OFFSHORE GRADIENTS WITH LAKE BREEZES EACH AFTERNOON...
ESPECIALLY TODAY (SATURDAY).
THE NEXT COLD FRONT IS DUE ON MONDAY AND THERE IS SOME QUESTION AS
TO THE TIMING OF THE FRONT. LOW PRESSURE IS EXPECTED TO DEVELOP
ALONG THE FRONT AND AS PRESSURES FALL TO THE WEST...THE WINDS COULD
BACK INSTEAD OF VEER. IN ANY CASE... WINDS SHOULD STILL BE RATHER
LIGHT AND MARINERS SHOULD CHECK THE LATEST FORECAST FOR THE
WIND/WAVES/WEATHER ON MONDAY AS SHOWERS AND THUNDERSTORMS ARE ALSO
POSSIBLE.
A NORTH TO NORTHEAST FLOW WILL PROBABLY OCCUR TUESDAY AND WEDNESDAY
NEXT WEEK AS HIGH PRESSURE BUILDS ACROSS EASTERN CANADA. THE
GRADIENT APPEARS AS THOUGH IT WILL BE RATHER LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
| 
