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000
FXUS61 KLWX 301339 AAA
AFDLWX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
939 AM EDT SAT APR 30 2016

.SYNOPSIS...
A FRONT WILL REMAIN STATIONARY ACROSS THE SOUTHERN MID ATLANTIC
STATES THROUGH TODAY. LOW PRESSURE MOVES THROUGH THE MID-
ATLANTIC SUNDAY INTO MONDAY...PULLING THE FRONT TO THE NORTH ON
SUNDAY...AND THEN SENDING A COLD FRONT ACROSS THE REGION ON
MONDAY. ANOTHER COLD FRONT WILL MOVE THROUGH LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
CWFA REMAINS WELL ENTRENCHED IN COLD AIR DAMMING WITH A STRONG
INVERSION AND NORTHEAST WINDS EVIDENT ON 12Z IAD RAOB. MORNING
WILL REMAIN CLOUDY AND DRY DUE TO DRY MID-LEVELS BUT FORCING FOR
ASCENT AND MOISTENING IN THE MID LEVELS WILL BEGIN TO OCCUR IN
THE AFTERNOON WITH RAIN BEGINNING IN THE POTOMAC HIGHLANDS AFTER
2PM AND LIKELY TO REACH THE I-81 CORRIDOR BY 8PM. RAIN IS EXPECTED
TONIGHT AS H85 FRONT LIFTS THROUGH THE AREA. ACCUMS TONIGHT WILL
RANGE BETWEEN A QUARTER TO HALF INCH.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
THERE LKLY WL BE LINGERING RAFL IN THE SRN CNTYS AT THE START OF
SUNDAY...BUT IT/LL BE EXITING TO THE EAST ALONG WITH THE LEADING
EDGE OF THE THTE RDG. THAT SHUD RESULT IN A PD OF DRYING...AND HV
ATTEMPTED TO REFLECT THAT BY LWRG OF POPS INTO CHC FOR THE MIDDAY.

SFC LOPRES AND H5 VORT TRACK UP THE OHVLY SUN-SUN NGT. THIS TRACK
WL ENCOURAGE STALLED BNDRY TO LIFT NWD...BUT IT/LL RUN INTO THE
STUBBORN CAD WEDGE. THIS PTTN ALWAYS A CHALLENGE FOR MDLS TO
FCST...AND THE RESULT USUALLY FAVORS PERSISTENCE. AM BEGINNING TO
ACTUALLY SEE THAT REFLECTED IN GDNC...SPCLY IN THE GFS...WHICH
HOLDS ONTO A STBL SFC LYR IN MD THRU THE DAY. BEST H8-5 LAPSE
RATES HOLD OVER THE APLCNS...BUT THERE CUD BE A LTL ELEVATED
INSTBY NE OF THERE.

THE MIDDAY DRYING AND HEATING SHUD PERMIT AFTN SHRA/TSRA TO DVLP.
IN DEFERENCE TO CLIMO...HV PULLED BACK ON THUNDER POTL THIS FCST
CYCLE. STILL SEE ENUF INSTBY/SHEAR SW OF BNDRY FOR TSTMS TO DVLP.
CHALLENGE WL E TO PINPOINT WHERE THAT AREA IS. ATTM WL PAINT IT S
OF CHO-SHD-EKN... FOR LATE IN THE DAY. SPC HAS PEGGED THAT AREA
FOR A MRGL RISK OF SVR. WL HV A THUNDER GRADIENT NEWD FM THERE.
SCHC THUNDER NE OF MRB-DCA WUD ONLY BE FOR A STRAY LATE DAY ELEV
RUMBLE. BEST LIFT WL ACTUALLY BE IN THAT AFOREMENTIONED AREA...ACRS
THE N/NERN CWFA...AGAIN DUE TO UPGLIDE. AFTN POPS WL HOVER IN THE
70-80 PCT RANGE.

SHUD LOSE ANY SFC-BASED INSTBY INSTBY W/ SUNSET...BUT LAPSE RATES
AND SHEAR REMAIN DECENT WELL INTO SUN NGT. THE PARENT LOW WL TRACK
TWD NEW ENGLAND...WHICH WL SEND THE CDFNT THRU OVNGT SUN OR MORE
LKLY MON MRNG. POPS GRDLY TAPER OFF THRU THAT PD. QPF POTL STILL
GOOD SUN EVE...AND WL CARRY SHRA W/ MDT RAFL AT THAT TIME. WL
TAPER OFF THEREAFTER. LKLY TO SEE SOME SUNSHINE BY MON AFTN.

TEMPS THIS PD REMAIN A CHALLENGE AS INSOLATION CUD RSLT IN TEMP
SPIKES. SUN MAXT REFLECT THAT GRADIENT ACRS CWFA. BETTER DRYING
AND SUBSIDENT WLY FLOW MON SUGGESTS THAT MON WL BE A WARMER DAY
REGARDLESS OF CFP.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
THE SYNOPSIS FOR NEXT WEEK WILL REMAIN COOL AND UNSETTLED. THE
MIDDLE PORTION OF THE WEEK FEATURES THE GREATEST UNCERTAINTY IN
TERMS OF SENSIBLE WEATHER IMPACTS. THE FRONT WHICH PASSES THROUGH
DURING THE EARLY PART OF THE WEEK WILL STALL ALONG THE SOUTHEAST
COAST WHILE TROUGHING ALOFT DEVELOPS OVER EASTERN NOAM.
MULTIPLE AREAS OF LOW PRESSURE WILL TRACK ALONG THE FRONT. IN
TERMS OF THE 00Z RUNS...ECMWF AND GEM OFFER WETTER SOLUTIONS (I.E.
LOW TRACKS CLOSER TO THE COAST) FOR THE LOCAL AREA...WHILE THE GFS
IS DRIER. WILL BE CARRYING LOW POPS ALMOST EVERY PERIOD AS TIMING
AND PLACEMENT DIFFERENCES WILL SPAN ACROSS THE DAY-PARTS OF THE
FORECAST. DESPITE THE PESSIMISTIC FORECAST...TOTAL RAINFALL AMOUNTS
SHOULD BE FAIRLY LIGHT UNLESS THE LOW TRACKS ARE MUCH FURTHER INLAND
THAN CURRENTLY FORECAST.

BY THURSDAY...ENERGY DIVING SE FROM CENTRAL CANADA WILL SEND A COLD
FRONT THROUGH THE REGION. AS THIS ENERGY INTERACTS WITH THE COASTAL
FRONT...A CLOSED LOW ALOFT IS EXPECTED TO DEVELOP. THIS WILL BE THE
EASTERN LOBE OF A DEVELOPING OMEGA BLOCK FOR THE END OF THE WEEK /
NEXT WEEKEND. THE RESULT WILL BE A SHOWERY PATTERN WITH PERHAPS
SOME LOW TOPPED CONVECTION. WITH NO REAL SOURCE OF WAA...TEMPERATURES
WILL LIKELY REMAIN BELOW NORMAL THROUGH THE WEEK. WITH THE STEEP
LAPSE RATES...THE ALLEGHENY FRONT MAY NOT BE TOO FAR FROM SEEING
SOME WET SNOW FLAKES MIX IN BY FRIDAY MORNING.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
CONDS WL GRDLY IMPRV DURING THE DAY. AM STARTING TO FEEL
CONFIDENT ENUF TO CARVE OUT A PD OF VFR FOR BALT-DC TERMINALS MID-
LT AFTN.

FLGT CONDS WL DROP SAT EVE AS RA OVERSPREADS THE AREA. RA MAY BE
MDT TO BRIEFLY HVY SAT NGT INTO ELY SUN. FLGT RESTRICTIONS WL BE
WIDESPREAD...AT LEAST IFR IF NOT LIFR.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC LKLY
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. ONCE AGN XPCT
IMPRVMNT DURING THE DAY AS RAFL HEADS EAST. THAT WL RESULT IN A
RENEWED CHC AT SHRA DURING THE AFTN. CUD BE THUNDER TOO...SPCLY
INVOF CHO. CONDS BECOME MORE STBL TWD THE NE.

CDFNT WL CROSS THE TERMINALS ELY MON...WHICH SHUD RESULT IN W/NWLY
FLOW. MAY STILL HV RESTRICTIONS TO START...BUT AM HOPEFUL FOR
IMPROVEMENT TO VFR DURING THE DAY.

LOW CONFIDENCE FORECAST FOR TUESDAY-WEDNESDAY WITH FRONT STALLED
ALONG SE COAST. GFS SUGGESTS MAINLY VFR WHILE OTHER MODELS WOULD
BRING IN SOME PERIODS OF RAIN AND POSSIBLE IMPACTS TO CIGS/VSBYS.

&&

.MARINE...
LLVLS REMAIN STBL THROUGH THE WKND AS A WEDGE OF HIPRES REMAINS
TRAPPED E OF THE BLURDG. THAT WL RESULT IN MAINLY E FLOW AT 5 TO
10 KT...WITH OCNL PDS CLSR TO 15 KT. WNDS WL VEER A BIT MORE TWD
THE SE AS AN APPCHG WMFNT TRIES TO DISLODGE THE MARINE AMS. ALTHO
WINDS WL BE STRONGER ALOFT...DONT BELIEVE THE STBL LLVLS WL PERMIT
ANY STRONGER WINDS TO REACH THE WATERS EDGE. THEREFORE...HV BACKED
AWAY FROM SCA POTL.

LIGHT NW FLOW EXPECTED TUESDAY BEHIND DEPARTED COLD FRONT. WINDS MAY
BECOME SW BY WEDNESDAY BUT GRADIENT LOOKS WEAK ENOUGH TO KEEP WINDS
AT 10-15 KT. SHOULD A STRONGER LOW PRESSURE SYSTEM DEVELOP ALONG A
STALLED COASTAL FRONT...HIGHER WINDS MAY BE REALIZED.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES REMAIN AROUND THREE QUARTERS TO A FOOT ABOVE
NORMAL. A PERSISTENT ONSHORE FLOW WILL CAUSE ANOMALIES TO HOLD
NEARLY STEADY OR EVEN INCREASE A BIT THROUGH THE WEEKEND.
HOWEVER...THE FLOW SHOULD BE LIGHT ENOUGH FOR WATER LEVELS TO
REMAIN BELOW MINOR FLOODING THRESHOLDS. THERES ROOM FOR THIS
FORECAST TO CHANGE...ESPECIALLY TOWARD SUNDAY...SO WE WILL
CONTINUE TO MONITOR THIS SITUATION.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...LFR
NEAR TERM...LFR
SHORT TERM...HTS
LONG TERM...ADS
AVIATION...ADS/HTS
MARINE...ADS/HTS
TIDES/COASTAL FLOODING...LFR/HTS





000
FXUS61 KLWX 300743
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
343 AM EDT SAT APR 30 2016

.SYNOPSIS...
A STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA TODAY. LOW
PRESSURE MOVES THROUGH THE MID- ATLANTIC SUNDAY INTO MONDAY...
PULLING THE FRONT TO THE NORTH ON SUNDAY...AND THEN SENDING A COLD
FRONT ACROSS THE REGION ON MONDAY. ANOTHER COLD FRONT WILL MOVE
THROUGH LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
CWFA REMAINS WITHIN AREA OF COLD AIR DAMMING...AND THIS WEDGE
APPEARS TO HOLD THROUGH THE DAY. THE RDGG DOWN THE COAST FM THE
GRTLKS APPEARS TO STRENGTHEN THRU THE DAY...WHICH HAS KEPT AREA
DRY OVNGT /ASIDE FM ANY PATCHY DZ/ AND SHUD HOLD OFF ANY APPRCHG
RAFL. AM SEEING THESE TRENDS IN LTST GFS/NAM RUNS...AND ITS SPCLY
PREVALENT IN RECENT RAP/HRRR/WRF-ARW4 RUNS. HV THEREFORE BACKED
OFF ON ARRIVAL OF PCPN TDA. THERE IS STILL A RIBBON OF STRONG
ISENT LIFT AHD OF LOPRES IN THE SRN PLAINS...AND PWATS STILL RISE
ABV AN INCH BY DAYS END.

THE IMPACT OF THESE TRENDS ARE TO KEEP PCPN OUT OF THE FCST
ENTIRELY IN NE MD TDA. ONLY CENTRAL FOOTHILLS/CENTRAL SHEN
VLY/SRN PTMC HIGHLANDS HV POPS HIER THAN LKLY-- AND THATS FOR ONLY
THE MID/LATE AFTN HRS. THE DAY WL START CLDY AND GREY AREAWIDE.
AS HIPRES WL BRIEFLY BE CONTROLLING...CLDS SHUD LIFT... AND MAY
SEE A FEW BRIGHT SPOTS. MAXT FCST WL REFLECT LESS OF A GRADIENT...
ALTHO BELIEVE THERE WL BE A LARGE MARGIN FOR ERROR CONTINGENT ON
IF/WHERE ANY SUN APPEARS.

THTE RDG/MSTR PLUME WL OVERSPREAD CWFA TNGT. POPS INCR TO CAT W/
POCKETS OF MDT RAFL. BASICALLY...IT WL BE A RAINY NGT...BUT NOT AT
A PACE WHERE FLOODING WUD BE A CONCERN.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
THERE LKLY WL BE LINGERING RAFL IN THE SRN CNTYS AT THE START OF
SUNDAY...BUT IT/LL BE EXITING TO THE EAST ALONG WITH THE LEADING
EDGE OF THE THTE RDG. THAT SHUD RESULT IN A PD OF DRYING...AND HV
ATTEMPTED TO REFLECT THAT BY LWRG OF POPS INTO CHC FOR THE MIDDAY.

SFC LOPRES AND H5 VORT TRACK UP THE OHVLY SUN-SUN NGT. THIS TRACK
WL ENCOURAGE STALLED BNDRY TO LIFT NWD...BUT IT/LL RUN INTO THE
STUBBORN CAD WEDGE. THIS PTTN ALWAYS A CHALLENGE FOR MDLS TO
FCST...AND THE RESULT USUALLY FAVORS PERSISTENCE. AM BEGINNING TO
ACTUALLY SEE THAT REFLECTED IN GDNC...SPCLY IN THE GFS...WHICH
HOLDS ONTO A STBL SFC LYR IN MD THRU THE DAY. BEST H8-5 LAPSE
RATES HOLD OVER THE APLCNS...BUT THERE CUD BE A LTL ELEVATED
INSTBY NE OF THERE.

THE MIDDAY DRYING AND HEATING SHUD PERMIT AFTN SHRA/TSRA TO DVLP.
IN DEFERENCE TO CLIMO...HV PULLED BACK ON THUNDER POTL THIS FCST
CYCLE. STILL SEE ENUF INSTBY/SHEAR SW OF BNDRY FOR TSTMS TO DVLP.
CHALLENGE WL E TO PINPOINT WHERE THAT AREA IS. ATTM WL PAINT IT S
OF CHO-SHD-EKN... FOR LATE IN THE DAY. SPC HAS PEGGED THAT AREA
FOR A MRGL RISK OF SVR. WL HV A THUNDER GRADIENT NEWD FM THERE.
SCHC THUNDER NE OF MRB-DCA WUD ONLY BE FOR A STRAY LATE DAY ELEV
RUMBLE. BEST LIFT WL ACTUALLY BE IN THAT AFOREMENTIONED AREA...ACRS
THE N/NERN CWFA...AGAIN DUE TO UPGLIDE. AFTN POPS WL HOVER IN THE
70-80 PCT RANGE.

SHUD LOSE ANY SFC-BASED INSTBY INSTBY W/ SUNSET...BUT LAPSE RATES
AND SHEAR REMAIN DECENT WELL INTO SUN NGT. THE PARENT LOW WL TRACK
TWD NEW ENGLAND...WHICH WL SEND THE CDFNT THRU OVNGT SUN OR MORE
LKLY MON MRNG. POPS GRDLY TAPER OFF THRU THAT PD. QPF POTL STILL
GOOD SUN EVE...AND WL CARRY SHRA W/ MDT RAFL AT THAT TIME. WL
TAPER OFF THEREAFTER. LKLY TO SEE SOME SUNSHINE BY MON AFTN.

TEMPS THIS PD REMAIN A CHALLENGE AS INSOLATION CUD RSLT IN TEMP
SPIKES. SUN MAXT REFLECT THAT GRADIENT ACRS CWFA. BETTER DRYING
AND SUBSIDENT WLY FLOW MON SUGGESTS THAT MON WL BE A WARMER DAY
REGARDLESS OF CFP.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
THE SYNOPSIS FOR NEXT WEEK WILL REMAIN COOL AND UNSETTLED. THE
MIDDLE PORTION OF THE WEEK FEATURES THE GREATEST UNCERTAINTY IN
TERMS OF SENSIBLE WEATHER IMPACTS. THE FRONT WHICH PASSES THROUGH
DURING THE EARLY PART OF THE WEEK WILL STALL ALONG THE SOUTHEAST
COAST WHILE TROUGHING ALOFT DEVELOPS OVER EASTERN NOAM.
MULTIPLE AREAS OF LOW PRESSURE WILL TRACK ALONG THE FRONT. IN
TERMS OF THE 00Z RUNS...ECMWF AND GEM OFFER WETTER SOLUTIONS (I.E.
LOW TRACKS CLOSER TO THE COAST) FOR THE LOCAL AREA...WHILE THE GFS
IS DRIER. WILL BE CARRYING LOW POPS ALMOST EVERY PERIOD AS TIMING
AND PLACEMENT DIFFERENCES WILL SPAN ACROSS THE DAY-PARTS OF THE
FORECAST. DESPITE THE PESSIMISTIC FORECAST...TOTAL RAINFALL AMOUNTS
SHOULD BE FAIRLY LIGHT UNLESS THE LOW TRACKS ARE MUCH FURTHER INLAND
THAN CURRENTLY FORECAST.

BY THURSDAY...ENERGY DIVING SE FROM CENTRAL CANADA WILL SEND A COLD
FRONT THROUGH THE REGION. AS THIS ENERGY INTERACTS WITH THE COASTAL
FRONT...A CLOSED LOW ALOFT IS EXPECTED TO DEVELOP. THIS WILL BE THE
EASTERN LOBE OF A DEVELOPING OMEGA BLOCK FOR THE END OF THE WEEK /
NEXT WEEKEND. THE RESULT WILL BE A SHOWERY PATTERN WITH PERHAPS
SOME LOW TOPPED CONVECTION. WITH NO REAL SOURCE OF WAA...TEMPERATURES
WILL LIKELY REMAIN BELOW NORMAL THROUGH THE WEEK. WITH THE STEEP
LAPSE RATES...THE ALLEGHENY FRONT MAY NOT BE TOO FAR FROM SEEING
SOME WET SNOW FLAKES MIX IN BY FRIDAY MORNING.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
LOW CLOUDS AND PATCHY DRIZZLE CONT ACRS THE TERMINALS ELY THIS
MRNG. RESTRICTIONS...MAINLY IFR...ARE A RESULT OF CIGS. CUD BE
HEADED TWD LIFR TWD SR. ALREADY SEEING HINTS OF THAT AT CHO.

CONDS WL GRDLY IMPRV DURING THE DAY. AM STARTING TO FEEL CONFIDENT
ENUF TO CARVE OUT A PD OF VFR FOR BALT-DC TERMINALS MID-LT AFTN.

FLGT CONDS WL DROP SAT EVE AS RA OVERSPREADS THE AREA. RA MAY BE
MDT TO BRIEFLY HVY SAT NGT INTO ELY SUN. FLGT RESTRICTIONS WL BE
WIDESPREAD...AT LEAST IFR IF NOT LIFR.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC LKLY
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. ONCE AGN XPCT
IMPRVMNT DURING THE DAY AS RAFL HEADS EAST. THAT WL RESULT IN A
RENEWED CHC AT SHRA DURING THE AFTN. CUD BE THUNDER TOO...SPCLY
INVOF CHO. CONDS BECOME MORE STBL TWD THE NE.

CDFNT WL CROSS THE TERMINALS ELY MON...WHICH SHUD RESULT IN W/NWLY
FLOW. MAY STILL HV RESTRICTIONS TO START...BUT AM HOPEFUL FOR
IMPROVEMENT TO VFR DURING THE DAY.

LOW CONFIDENCE FORECAST FOR TUESDAY-WEDNESDAY WITH FRONT STALLED
ALONG SE COAST. GFS SUGGESTS MAINLY VFR WHILE OTHER MODELS WOULD
BRING IN SOME PERIODS OF RAIN AND POSSIBLE IMPACTS TO CIGS/VSBYS.

&&

.MARINE...
LLVLS REMAIN STBL THROUGH THE WKND AS A WEDGE OF HIPRES REMAINS
TRAPPED E OF THE BLURDG. THAT WL RESULT IN MAINLY E FLOW AT 5 TO
10 KT...WITH OCNL PDS CLSR TO 15 KT. WNDS WL VEER A BIT MORE TWD
THE SE AS AN APPCHG WMFNT TRIES TO DISLODGE THE MARINE AMS. ALTHO
WINDS WL BE STRONGER ALOFT...DONT BELIEVE THE STBL LLVLS WL PERMIT
ANY STRONGER WINDS TO REACH THE WATERS EDGE. THEREFORE...HV BACKED
AWAY FROM SCA POTL.

LIGHT NW FLOW EXPECTED TUESDAY BEHIND DEPARTED COLD FRONT. WINDS MAY
BECOME SW BY WEDNESDAY BUT GRADIENT LOOKS WEAK ENOUGH TO KEEP WINDS
AT 10-15 KT. SHOULD A STRONGER LOW PRESSURE SYSTEM DEVELOP ALONG A
STALLED COASTAL FRONT...HIGHER WINDS MAY BE REALIZED.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES REMAIN AROUND ONE-HALF TO THREE QUARTERS OF A
FOOT ABOVE NORMAL. A PERSISTENT ONSHORE FLOW WILL CAUSE ANOMALIES
TO HOLD NEARLY STEADY OR EVEN INCREASE A BIT THROUGH THE WEEKEND.
HOWEVER...THE FLOW SHOULD BE LIGHT ENOUGH FOR WATER LEVELS TO
REMAIN BELOW MINOR FLOODING THRESHOLDS. THERES ROOM FOR THIS
FORECAST TO CHANGE...ESPECIALLY TOWARD SUNDAY...SO WE WILL
CONTINUE TO MONITOR THIS SITUATION.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...ADS
AVIATION...HTS/ADS
MARINE...HTS/ADS
TIDES/COASTAL FLOODING...HTS





000
FXUS61 KLWX 300051
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
851 PM EDT FRI APR 29 2016

.SYNOPSIS...
STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA THROUGH
SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE MID- ATLANTIC
SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH LATER NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A BOUNDARY REMAINS NEARLY STATIONARY ACROSS THE ALLEGHENY
HIGHLANDS SOUTHEAST INTO NORTH CAROLINA THIS EVENING. A SHORTWAVE
IS PASSING BY TO THE NORTH AS WELL.

AN EAST TO NORTHEAST FLOW WILL CONTINUE TO USHER IN COOL
CONDITIONS ACROSS OUR CWA BEHIND THE BOUNDARY. THE ONSHORE FLOW
WILL CONTINUE TO CAUSE MOISTURE TO BE TRAPPED UNDERNEATH THE
SUBSIDENCE INVERSION...RESULTING IN LOW CLOUDS ALONG WITH PATCHY
FOG. FOG MAY BE LOCALLY DENSE ACROSS THE HIGHER ELEVATIONS ABOVE
2KFT. THE SHORTWAVE HAS TRIGGERED LIGHT RAIN ACROSS NORTHERN
PORTIONS OF THE CWA...BUT RAINFALL COVERAGE IS LIMITED SINCE MOST
OF THE FORCING IS OFF TO THE NORTH. THE SHORTWAVE WILL MOVE AWAY
FROM THE AREA OVERNIGHT...BRINGING ANY STEADY RAIN WITH IT.
HOWEVER...OCCASIONAL DRIZZLE WILL CONTINUE THROUGH TONIGHT DUE TO
THE ONSHORE FLOW. MIN TEMPS TONIGHT WILL RANGE FROM THE MID TO
UPPER 40S ACROSS NORTHERN MARYLAND TO THE LOWER AND MIDDLE 50S IN
CENTRAL VIRGINIA.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
THE MOST RECENT MDL RUNS /06Z AND 12Z/ ARE TRENDING WETTER...AND
THUS HV INCREASED POPS A PINCH FOR LATE DAY SAT...AND FURTHER INTO
CAT TERRITORY FOR SAT NGT AND SUN.

SAT CULPRIT WL BE ISENT LIFT...WHICH IMPRV THRU THE DAY. BY LT
DAY...HV LKLY POPS. A SOLID SWATH OF MSTR EMINATES FM THE GLFMEX
/PWAT EXCEEDS AN INCH/...WHICH SUPPORTS DECISION TO INCR TO CAT
POPS BY SAT NGT...AS WELL AS INCR TO MDT RAFL IN OUR DATABASE.

SFC LOPRES AND H5 VORT TRACK ALONG THE STALLED BNDRY UP THE OHVLY
SUN INTO SUN NGT. THIS PATH TAKES THE BNDRY N OF THE CWA...AND
DISLODGES LLVL WEDGE. AM A BIT SKEPTICAL OF FULL SCOURING DUE TO
CLIMO...BUT AT THE VERY LEAST IT APPEARS AS THOUGH THERE WL BE AN
ELEVATED UNSTBL LYR. ISENT LIFT/MSTR ADVCTN WL CONT TO FUEL THIS
SYSTEM. AM ATTEMPTING TO PROVIDE A LTL DEFINITION BY CAPTURING A
DIURNAL MIN /RELATIVELY SPEAKING/ IN THE MRNG...FLLWD BY CAT POPS
WHEN DAYTIME HEATING WL HV THE BIGGER IMPACT. IN ADDITION...AM A
LTL MORE EXPANSIVE IN AREA OF CHC THUNDER...AT LEAST FM AN
ELEVATED SENSE. SHEAR LOOKS GOOD...BUT AM CHALLENGED TO SEE TOO
MUCH SFC BASED INSTBY.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
LOW PRESSURE DEPARTS TO THE NORTHEAST MONDAY...BUT THE FRONTAL
BOUNDARY IT RODE IN ON WILL REMAIN STALLED NEAR THE REGION THROUGH
MUCH OF NEXT WEEK. MULTIPLE AREAS OF LOW PRESSURE WILL CONTINUE TO
DEVELOP AND MOVE ALONG IT...AS THE LARGE SCALE TROUGH RESPONSIBLE
FOR THIS ACTIVE PATTERN PERSISTS OVER EASTERN NORTH AMERICA. THIS
WILL ALSO LEAD TO BELOW NORMAL TEMPERATURES THROUGH MUCH OF NEXT
WEEK...WITH HIGHS STRUGGLING TO REACH 70.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
LOW CLOUDS AND DRIZZLE WILL CONTINUE BEHIND A BOUNDARY OVER THE
ALLEGHENY HIGHLANDS TONIGHT. IFR CIGS ALONG WITH MVFR AND IFR
VSBYS ARE EXPECTED DURING THIS TIME. CONDS WL GRDLY IMPRV
SAT...ALTHO FLGT RESTRICTIONS REMAIN. THERE IS A CHC AT BRIEF
VFR PRIOR TO RAFL ARRIVING. ATTM CONFIDENCE TOO LOW TO CARVE OUT A
WINDOW OF VFR IN THE TAFS.

LT AFTN OR EVE SAT CONDS WL DROP AS RA OVERSPREADS THE AREA. RA
MAY BE MDT TO BRIEFLY HVY SAT NGT INTO SUN. FLGT RESTRICTIONS WL
BE WIDESPREAD.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC PSBL
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. HWVR THAT ALSO
YIELDS A THUNDER RISK.

SUB-VFR PSBL MON-TUE IN ANY LWR CIGS/-RA W/ FRONT STALLED NEARBY.
WINDS GENERALLY NELY 10 KTS.

&&

.MARINE...
PREV FCST REMAINS ON TRACK. ONSHORE FLOW WILL CONTINUE THROUGH
SATURDAY. GENERALLY EXPECTING 5- 10 KT WITH OCCASIONAL INCREASES
TO 15 KT. LIGHT FOG AND DZ WILL CONTINUE AT TIMES.

NEXT ROUND OF RAIN AND ASSOCIATED LLJ REACHES WATERS BY ELY SAT
EVNG. AM KEEPING WINDS UNDER SCA CRITERIA THRU SAT NGT EVEN THO
WINDS ALOFT INCREASE DUE TO POOR MIXING. MIXING MAY IMPROVE ON
SUN...PSBLY AFTN/EVE...BUT CONFIDENCE ON THAT RATHER LOW.

THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA
CONDITIONS ALSO REMAIN POSSIBLE SUN-MON WITH LOW PRESSURE PASSING
ON MONDAY.

A FRONTAL BOUNDARY STALLED NEAR OR JUST SOUTH OF THE WATERS
SHOULD RESULT IN A WEAK ENOUGH GRADIENT TO PRECLUDE SMALL CRAFT
ADVISORIES MONDAY INTO TUESDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES ARE AROUND ONE-HALF TO THREE QUARTERS OF A FOOT
ABOVE NORMAL. A PERSISTENT ONSHORE FLOW WILL CAUSE ANOMALIES TO
HOLD NEARLY STEADY OR EVEN INCREASE A BIT THROUGH SATURDAY.
HOWEVER...THE FLOW SHOULD BE LIGHT ENOUGH FOR WATER LEVELS TO
REMAIN BELOW MINOR FLOODING THRESHOLDS. THE FLOW MAY STRENGTHEN A
BIT SUNDAY...CAUSING WATER LEVELS TO APPROACH MINOR FLOODING
THRESHOLDS BUT CONFIDENCE REMAINS LOW AT THIS TIME.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM/HTS
NEAR TERM...BJL/HTS
SHORT TERM...HTS
LONG TERM...DFH
AVIATION...BJL/HTS/DFH
MARINE...BJL/DFH
TIDES/COASTAL FLOODING...BJL





000
FXUS61 KLWX 300051
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
851 PM EDT FRI APR 29 2016

.SYNOPSIS...
STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA THROUGH
SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE MID- ATLANTIC
SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH LATER NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A BOUNDARY REMAINS NEARLY STATIONARY ACROSS THE ALLEGHENY
HIGHLANDS SOUTHEAST INTO NORTH CAROLINA THIS EVENING. A SHORTWAVE
IS PASSING BY TO THE NORTH AS WELL.

AN EAST TO NORTHEAST FLOW WILL CONTINUE TO USHER IN COOL
CONDITIONS ACROSS OUR CWA BEHIND THE BOUNDARY. THE ONSHORE FLOW
WILL CONTINUE TO CAUSE MOISTURE TO BE TRAPPED UNDERNEATH THE
SUBSIDENCE INVERSION...RESULTING IN LOW CLOUDS ALONG WITH PATCHY
FOG. FOG MAY BE LOCALLY DENSE ACROSS THE HIGHER ELEVATIONS ABOVE
2KFT. THE SHORTWAVE HAS TRIGGERED LIGHT RAIN ACROSS NORTHERN
PORTIONS OF THE CWA...BUT RAINFALL COVERAGE IS LIMITED SINCE MOST
OF THE FORCING IS OFF TO THE NORTH. THE SHORTWAVE WILL MOVE AWAY
FROM THE AREA OVERNIGHT...BRINGING ANY STEADY RAIN WITH IT.
HOWEVER...OCCASIONAL DRIZZLE WILL CONTINUE THROUGH TONIGHT DUE TO
THE ONSHORE FLOW. MIN TEMPS TONIGHT WILL RANGE FROM THE MID TO
UPPER 40S ACROSS NORTHERN MARYLAND TO THE LOWER AND MIDDLE 50S IN
CENTRAL VIRGINIA.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
THE MOST RECENT MDL RUNS /06Z AND 12Z/ ARE TRENDING WETTER...AND
THUS HV INCREASED POPS A PINCH FOR LATE DAY SAT...AND FURTHER INTO
CAT TERRITORY FOR SAT NGT AND SUN.

SAT CULPRIT WL BE ISENT LIFT...WHICH IMPRV THRU THE DAY. BY LT
DAY...HV LKLY POPS. A SOLID SWATH OF MSTR EMINATES FM THE GLFMEX
/PWAT EXCEEDS AN INCH/...WHICH SUPPORTS DECISION TO INCR TO CAT
POPS BY SAT NGT...AS WELL AS INCR TO MDT RAFL IN OUR DATABASE.

SFC LOPRES AND H5 VORT TRACK ALONG THE STALLED BNDRY UP THE OHVLY
SUN INTO SUN NGT. THIS PATH TAKES THE BNDRY N OF THE CWA...AND
DISLODGES LLVL WEDGE. AM A BIT SKEPTICAL OF FULL SCOURING DUE TO
CLIMO...BUT AT THE VERY LEAST IT APPEARS AS THOUGH THERE WL BE AN
ELEVATED UNSTBL LYR. ISENT LIFT/MSTR ADVCTN WL CONT TO FUEL THIS
SYSTEM. AM ATTEMPTING TO PROVIDE A LTL DEFINITION BY CAPTURING A
DIURNAL MIN /RELATIVELY SPEAKING/ IN THE MRNG...FLLWD BY CAT POPS
WHEN DAYTIME HEATING WL HV THE BIGGER IMPACT. IN ADDITION...AM A
LTL MORE EXPANSIVE IN AREA OF CHC THUNDER...AT LEAST FM AN
ELEVATED SENSE. SHEAR LOOKS GOOD...BUT AM CHALLENGED TO SEE TOO
MUCH SFC BASED INSTBY.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
LOW PRESSURE DEPARTS TO THE NORTHEAST MONDAY...BUT THE FRONTAL
BOUNDARY IT RODE IN ON WILL REMAIN STALLED NEAR THE REGION THROUGH
MUCH OF NEXT WEEK. MULTIPLE AREAS OF LOW PRESSURE WILL CONTINUE TO
DEVELOP AND MOVE ALONG IT...AS THE LARGE SCALE TROUGH RESPONSIBLE
FOR THIS ACTIVE PATTERN PERSISTS OVER EASTERN NORTH AMERICA. THIS
WILL ALSO LEAD TO BELOW NORMAL TEMPERATURES THROUGH MUCH OF NEXT
WEEK...WITH HIGHS STRUGGLING TO REACH 70.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
LOW CLOUDS AND DRIZZLE WILL CONTINUE BEHIND A BOUNDARY OVER THE
ALLEGHENY HIGHLANDS TONIGHT. IFR CIGS ALONG WITH MVFR AND IFR
VSBYS ARE EXPECTED DURING THIS TIME. CONDS WL GRDLY IMPRV
SAT...ALTHO FLGT RESTRICTIONS REMAIN. THERE IS A CHC AT BRIEF
VFR PRIOR TO RAFL ARRIVING. ATTM CONFIDENCE TOO LOW TO CARVE OUT A
WINDOW OF VFR IN THE TAFS.

LT AFTN OR EVE SAT CONDS WL DROP AS RA OVERSPREADS THE AREA. RA
MAY BE MDT TO BRIEFLY HVY SAT NGT INTO SUN. FLGT RESTRICTIONS WL
BE WIDESPREAD.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC PSBL
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. HWVR THAT ALSO
YIELDS A THUNDER RISK.

SUB-VFR PSBL MON-TUE IN ANY LWR CIGS/-RA W/ FRONT STALLED NEARBY.
WINDS GENERALLY NELY 10 KTS.

&&

.MARINE...
PREV FCST REMAINS ON TRACK. ONSHORE FLOW WILL CONTINUE THROUGH
SATURDAY. GENERALLY EXPECTING 5- 10 KT WITH OCCASIONAL INCREASES
TO 15 KT. LIGHT FOG AND DZ WILL CONTINUE AT TIMES.

NEXT ROUND OF RAIN AND ASSOCIATED LLJ REACHES WATERS BY ELY SAT
EVNG. AM KEEPING WINDS UNDER SCA CRITERIA THRU SAT NGT EVEN THO
WINDS ALOFT INCREASE DUE TO POOR MIXING. MIXING MAY IMPROVE ON
SUN...PSBLY AFTN/EVE...BUT CONFIDENCE ON THAT RATHER LOW.

THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA
CONDITIONS ALSO REMAIN POSSIBLE SUN-MON WITH LOW PRESSURE PASSING
ON MONDAY.

A FRONTAL BOUNDARY STALLED NEAR OR JUST SOUTH OF THE WATERS
SHOULD RESULT IN A WEAK ENOUGH GRADIENT TO PRECLUDE SMALL CRAFT
ADVISORIES MONDAY INTO TUESDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES ARE AROUND ONE-HALF TO THREE QUARTERS OF A FOOT
ABOVE NORMAL. A PERSISTENT ONSHORE FLOW WILL CAUSE ANOMALIES TO
HOLD NEARLY STEADY OR EVEN INCREASE A BIT THROUGH SATURDAY.
HOWEVER...THE FLOW SHOULD BE LIGHT ENOUGH FOR WATER LEVELS TO
REMAIN BELOW MINOR FLOODING THRESHOLDS. THE FLOW MAY STRENGTHEN A
BIT SUNDAY...CAUSING WATER LEVELS TO APPROACH MINOR FLOODING
THRESHOLDS BUT CONFIDENCE REMAINS LOW AT THIS TIME.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM/HTS
NEAR TERM...BJL/HTS
SHORT TERM...HTS
LONG TERM...DFH
AVIATION...BJL/HTS/DFH
MARINE...BJL/DFH
TIDES/COASTAL FLOODING...BJL





000
FXUS61 KLWX 291915
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
315 PM EDT FRI APR 29 2016

.SYNOPSIS...
STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA THROUGH
SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE MID- ATLANTIC
SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH LATER NEXT
WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MRNG PCPN HAS LIFTED INTO PA. WEAK S/WV IN NW PA ATTM WL TRACK EWD
TAFTN-TNGT. THERE MAY BE A FEW ASSOCD SHRA IN CWFA...BUT UPSTREAM
RDR ATTM LOOKS UNIMPRESSIVE. HV BEEN TRIMMING POPS AND WL CONT
TO DO SO. THE MOST NOTICEABLE ASPECT OF THE FCST WL BE THE XTNSV
CLDCVR...WHICH AFFECTS MOST OF THE CWFA XCPT FOR THE CENTRAL SHEN
VLY AND MUCH OF THE APLCNS. STALLED BNDRY SEEMS TO HV WIGGLED NWD.
/EKN 2PM TEMP 70F WHILE DCA REMAINS AT 53F./ THE PASSAGE OF THE
VORT SHUD NUDGE IT SWD AGN.

FOR THE OVNGT HRS...CONTD OVERRUNNING SHUD SUPPORT DZ. THAT WL BE
THE PRIMARY PCPN WORDING FOR MUCH OF THE AREA TNGT. AM HOLDING W/
PERSISTENCE WRT MIN-T...WHICH MEANS 45-50F N AND LWR 50S S.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MOST RECENT MDL RUNS /06Z AND 12Z/ ARE TRENDING WETTER...AND
THUS HV INCREASED POPS A PINCH FOR LATE DAY SAT...AND FURTHER INTO
CAT TERRITORY FOR SAT NGT AND SUN.

SAT CULPRIT WL BE ISENT LIFT...WHICH IMPRV THRU THE DAY. BY LT
DAY...HV LKLY POPS. A SOLID SWATH OF MSTR EMINATES FM THE GLFMEX
/PWAT EXCEEDS AN INCH/...WHICH SUPPORTS DECISION TO INCR TO CAT
POPS BY SAT NGT...AS WELL AS INCR TO MDT RAFL IN OUR DATABASE.

SFC LOPRES AND H5 VORT TRACK ALONG THE STALLED BNDRY UP THE OHVLY
SUN INTO SUN NGT. THIS PATH TAKES THE BNDRY N OF THE CWA...AND
DISLODGES LLVL WEDGE. AM A BIT SKEPTICAL OF FULL SCOURING DUE TO
CLIMO...BUT AT THE VERY LEAST IT APPEARS AS THOUGH THERE WL BE AN
ELEVATED UNSTBL LYR. ISENT LIFT/MSTR ADVCTN WL CONT TO FUEL THIS
SYSTEM. AM ATTEMPTING TO PROVIDE A LTL DEFINITION BY CAPTURING A
DIURNAL MIN /RELATIVELY SPEAKING/ IN THE MRNG...FLLWD BY CAT POPS
WHEN DAYTIME HEATING WL HV THE BIGGER IMPACT. IN ADDITION...AM A
LTL MORE EXPANSIVE IN AREA OF CHC THUNDER...AT LEAST FM AN
ELEVATED SENSE. SHEAR LOOKS GOOD...BUT AM CHALLENGED TO SEE TOO
MUCH SFC BASED INSTBY.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
LOW PRESSURE DEPARTS TO THE NORTHEAST MONDAY...BUT THE FRONTAL
BOUNDARY IT RODE IN ON WILL REMAIN STALLED NEAR THE REGION THROUGH
MUCH OF NEXT WEEK. MULTIPLE AREAS OF LOW PRESSURE WILL CONTINUE TO
DEVELOP AND MOVE ALONG IT...AS THE LARGE SCALE TROUGH RESPONSIBLE
FOR THIS ACTIVE PATTERN PERSISTS OVER EASTERN NORTH AMERICA. THIS
WILL ALSO LEAD TO BELOW NORMAL TEMPERATURES THROUGH MUCH OF NEXT
WEEK...WITH HIGHS STRUGGLING TO REACH 70.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
FLGT CONDS ON THE CUSP BTWN MVFR AND IFR. BELIEVE WL HV IMPRVMNT
THRU THE AFTN BEFORE CONDS DROP ONCE AGN. HV KEPT ALL TAFS AT
MVFR TNGT...ALTHO IFR /OR LWR/ CERTAINLY WITHIN THE REALM OF
POSSIBILITY.

CONDS WL GRDLY IMPRV ONCE AGN SAT...ALTHO FLGT RESTRICTIONS
REMAIN. THERE IS A CHC AT BRIEF VFR PRIOR TO RAFL ARRIVING. ATTM
CONFIDENCE TOO LOW TO CARVE OUT A WINDOW OF VFR IN THE TAFS.

LT AFTN OR EVE SAT CONDS WL DROP AS RA OVERSPREADS THE AREA. RA
MAY BE MDT TO BRIEFLY HVY SAT NGT INTO SUN. FLGT RESTRICTIONS WL
BE WIDESPREAD.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC PSBL
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. HWVR THAT ALSO
YIELDS A THUNDER RISK.

SUB-VFR PSBL MON-TUE IN ANY LWR CIGS/-RA W/ FRONT STALLED NEARBY.
WINDS GENERALLY NELY 10 KTS.

&&

.MARINE...
PREV FCST REMAINS ON TRACK. ONSHORE FLOW WILL CONTINUE THROUGH
SATURDAY. GENERALLY EXPECTING 5- 10 KT WITH OCCASIONAL INCREASES
TO 15 KT. LIGHT FOG AND DZ WILL CONTINUE AT TIMES.

NEXT ROUND OF RAIN AND ASSOCIATED LLJ REACHES WATERS BY ELY SAT
EVNG. AM KEEPING WINDS UNDER SCA CRITERIA THRU SAT NGT EVEN THO
WINDS ALOFT INCREASE DUE TO POOR MIXING. MIXING MAY IMPROVE ON
SUN...PSBLY AFTN/EVE...BUT CONFIDENCE ON THAT RATHER LOW.

THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA
CONDITIONS ALSO REMAIN POSSIBLE SUN-MON WITH LOW PRESSURE PASSING
ON MONDAY.

A FRONTAL BOUNDARY STALLED NEAR OR JUST SOUTH OF THE WATERS
SHOULD RESULT IN A WEAK ENOUGH GRADIENT TO PRECLUDE SMALL CRAFT
ADVISORIES MONDAY INTO TUESDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES STILL AT OR BELOW A HALF-FOOT ABV NORMAL. WL CONT
TO MONITOR...THERE ARE NO INDICATIONS OF POTL INUNDATION THRU THE
WKND. SUN COMES THE CLOSEST.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM/HTS
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...DFH
AVIATION...HTS/DFH
MARINE...HTS/DFH
TIDES/COASTAL FLOODING...HTS





000
FXUS61 KLWX 291915
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
315 PM EDT FRI APR 29 2016

.SYNOPSIS...
STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA THROUGH
SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE MID- ATLANTIC
SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH LATER NEXT
WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MRNG PCPN HAS LIFTED INTO PA. WEAK S/WV IN NW PA ATTM WL TRACK EWD
TAFTN-TNGT. THERE MAY BE A FEW ASSOCD SHRA IN CWFA...BUT UPSTREAM
RDR ATTM LOOKS UNIMPRESSIVE. HV BEEN TRIMMING POPS AND WL CONT
TO DO SO. THE MOST NOTICEABLE ASPECT OF THE FCST WL BE THE XTNSV
CLDCVR...WHICH AFFECTS MOST OF THE CWFA XCPT FOR THE CENTRAL SHEN
VLY AND MUCH OF THE APLCNS. STALLED BNDRY SEEMS TO HV WIGGLED NWD.
/EKN 2PM TEMP 70F WHILE DCA REMAINS AT 53F./ THE PASSAGE OF THE
VORT SHUD NUDGE IT SWD AGN.

FOR THE OVNGT HRS...CONTD OVERRUNNING SHUD SUPPORT DZ. THAT WL BE
THE PRIMARY PCPN WORDING FOR MUCH OF THE AREA TNGT. AM HOLDING W/
PERSISTENCE WRT MIN-T...WHICH MEANS 45-50F N AND LWR 50S S.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MOST RECENT MDL RUNS /06Z AND 12Z/ ARE TRENDING WETTER...AND
THUS HV INCREASED POPS A PINCH FOR LATE DAY SAT...AND FURTHER INTO
CAT TERRITORY FOR SAT NGT AND SUN.

SAT CULPRIT WL BE ISENT LIFT...WHICH IMPRV THRU THE DAY. BY LT
DAY...HV LKLY POPS. A SOLID SWATH OF MSTR EMINATES FM THE GLFMEX
/PWAT EXCEEDS AN INCH/...WHICH SUPPORTS DECISION TO INCR TO CAT
POPS BY SAT NGT...AS WELL AS INCR TO MDT RAFL IN OUR DATABASE.

SFC LOPRES AND H5 VORT TRACK ALONG THE STALLED BNDRY UP THE OHVLY
SUN INTO SUN NGT. THIS PATH TAKES THE BNDRY N OF THE CWA...AND
DISLODGES LLVL WEDGE. AM A BIT SKEPTICAL OF FULL SCOURING DUE TO
CLIMO...BUT AT THE VERY LEAST IT APPEARS AS THOUGH THERE WL BE AN
ELEVATED UNSTBL LYR. ISENT LIFT/MSTR ADVCTN WL CONT TO FUEL THIS
SYSTEM. AM ATTEMPTING TO PROVIDE A LTL DEFINITION BY CAPTURING A
DIURNAL MIN /RELATIVELY SPEAKING/ IN THE MRNG...FLLWD BY CAT POPS
WHEN DAYTIME HEATING WL HV THE BIGGER IMPACT. IN ADDITION...AM A
LTL MORE EXPANSIVE IN AREA OF CHC THUNDER...AT LEAST FM AN
ELEVATED SENSE. SHEAR LOOKS GOOD...BUT AM CHALLENGED TO SEE TOO
MUCH SFC BASED INSTBY.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
LOW PRESSURE DEPARTS TO THE NORTHEAST MONDAY...BUT THE FRONTAL
BOUNDARY IT RODE IN ON WILL REMAIN STALLED NEAR THE REGION THROUGH
MUCH OF NEXT WEEK. MULTIPLE AREAS OF LOW PRESSURE WILL CONTINUE TO
DEVELOP AND MOVE ALONG IT...AS THE LARGE SCALE TROUGH RESPONSIBLE
FOR THIS ACTIVE PATTERN PERSISTS OVER EASTERN NORTH AMERICA. THIS
WILL ALSO LEAD TO BELOW NORMAL TEMPERATURES THROUGH MUCH OF NEXT
WEEK...WITH HIGHS STRUGGLING TO REACH 70.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
FLGT CONDS ON THE CUSP BTWN MVFR AND IFR. BELIEVE WL HV IMPRVMNT
THRU THE AFTN BEFORE CONDS DROP ONCE AGN. HV KEPT ALL TAFS AT
MVFR TNGT...ALTHO IFR /OR LWR/ CERTAINLY WITHIN THE REALM OF
POSSIBILITY.

CONDS WL GRDLY IMPRV ONCE AGN SAT...ALTHO FLGT RESTRICTIONS
REMAIN. THERE IS A CHC AT BRIEF VFR PRIOR TO RAFL ARRIVING. ATTM
CONFIDENCE TOO LOW TO CARVE OUT A WINDOW OF VFR IN THE TAFS.

LT AFTN OR EVE SAT CONDS WL DROP AS RA OVERSPREADS THE AREA. RA
MAY BE MDT TO BRIEFLY HVY SAT NGT INTO SUN. FLGT RESTRICTIONS WL
BE WIDESPREAD.

POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC PSBL
AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. HWVR THAT ALSO
YIELDS A THUNDER RISK.

SUB-VFR PSBL MON-TUE IN ANY LWR CIGS/-RA W/ FRONT STALLED NEARBY.
WINDS GENERALLY NELY 10 KTS.

&&

.MARINE...
PREV FCST REMAINS ON TRACK. ONSHORE FLOW WILL CONTINUE THROUGH
SATURDAY. GENERALLY EXPECTING 5- 10 KT WITH OCCASIONAL INCREASES
TO 15 KT. LIGHT FOG AND DZ WILL CONTINUE AT TIMES.

NEXT ROUND OF RAIN AND ASSOCIATED LLJ REACHES WATERS BY ELY SAT
EVNG. AM KEEPING WINDS UNDER SCA CRITERIA THRU SAT NGT EVEN THO
WINDS ALOFT INCREASE DUE TO POOR MIXING. MIXING MAY IMPROVE ON
SUN...PSBLY AFTN/EVE...BUT CONFIDENCE ON THAT RATHER LOW.

THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA
CONDITIONS ALSO REMAIN POSSIBLE SUN-MON WITH LOW PRESSURE PASSING
ON MONDAY.

A FRONTAL BOUNDARY STALLED NEAR OR JUST SOUTH OF THE WATERS
SHOULD RESULT IN A WEAK ENOUGH GRADIENT TO PRECLUDE SMALL CRAFT
ADVISORIES MONDAY INTO TUESDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES STILL AT OR BELOW A HALF-FOOT ABV NORMAL. WL CONT
TO MONITOR...THERE ARE NO INDICATIONS OF POTL INUNDATION THRU THE
WKND. SUN COMES THE CLOSEST.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM/HTS
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...DFH
AVIATION...HTS/DFH
MARINE...HTS/DFH
TIDES/COASTAL FLOODING...HTS





000
FXUS61 KLWX 291403
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1003 AM EDT FRI APR 29 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH TODAY. ANOTHER WEAK
WAVE OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY. THE BOUNDARY
WILL DROP SOUTH SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE
MID-ATLANTIC SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH
LATER NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVE LULL IN ACTIVITY ACROSS THE AREA THIS MORNING...WITH
ONLY A FEW SHOWERS EMBEDDED WITHIN THE DZ AND LIGHT FOG...MAINLY
ACRS NE MD. WEDGE OF HIGH PRESSURE EVIDENT EAST OF THE MTNS IN
VA...WITH MAIN FRONT STILL DRAPED ACROSS NC.

ON THE WHOLE...FCST IN GOOD SHAPE. GUIDANCE HINTING THAT CLOUDS
MAY ERODE SOME BY THIS AFTERNOON ACROSS SOUTHWESTERN PORTIONS OF
THE AREA. PERHAPS NOT CLEARING...BUT AT LEAST LIFTING. ELSEWHERE
EXPECT LOW CLOUDS TO HOLD FIRM. THIS COULD LEAD TO A GRADIENT IN
TEMPERATURES...WITH COOLEST TO THE NE. HAVE SHADED A LITTLE BELOW
MODEL BLEND. BASED ON LTST LAMP...MAXT FCST SEEMS ON TRACK. W/ A
LACK OF ORGANIZED FORCING...IT SHOULD BE ONE OF THE DRIER PDS IN
THE NEXT CPL OF DAYS.

VORT MAX CURRENTLY OVER LAKE MICHIGAN WILL PASS TO THE NORTH LATE
THIS AFTERNOON. THIS WILL BRING A RENEWED CHANCE OF LIGHT SHOWERS
MOVING FROM NW TO SE ACROSS THE REGION. HAVE KEPT POPS AT CHANCE
GIVEN EXPECTED SCATTERED/LIGHT NATURE. THIS WILL ALSO SERVE TO GIVE
THE FRONTAL ZONE A NUDGE TO THE SOUTH AND DRY OUT THE ATMOSPHERE...
EXCEPT AT THE LOW LEVELS. WITH A CONTINUED OVERRUNNING FLOW...HAVE
KEPT PATCHY DZ WORDING IN THE FORECAST LATE TONIGHT. LIGHT FOG
POSSIBLE ONCE AGAIN TOO. SAME TREND...ONLY SMALL DROP IN TEMPS
OVERNIGHT.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE TREND FOR THE WEEKEND CONTINUES TO BE LESS DRY. NOT A TOTAL
WASHOUT...BUT PROLONGED BREAKS WILL BE SPARSE ONCE ISENTROPIC LIFT
BEGINS AHEAD OF LOW PRESSURE OVER THE PLAINS. RAIN COULD ARRIVE IN
THE MOUNTAINS SATURDAY MORNING...AND AT LEAST A CHANCE OF IT
SPREADING EAST DURING THE AFTERNOON. STILL SOME TIMING DIFFERENCES.
BUT BROUGHT POPS TO CATEGORICAL SATURDAY NIGHT AND WORDED AS
RAIN...LOOKS LIKE A GOOD SLUG OF MOISTURE...AND PERHAPS BE MODERATE
AT TIMES. TRENDED MAX T ON SATURDAY DOWN A LITTLE.

SFC LOW AND OPENING UPPER WAVE WILL BE APPROACHING THE OHIO VALLEY
SUNDAY INTO SUNDAY NIGHT. CONTINUED LIFT AND MOISTURE ADVECTION WILL
MEAN HIGH CHANCES OF SHOWERS CONTINUING. BIGGEST UNCERTAINTY IS WHAT
HAPPENS TO WEDGE FRONT ON SUNDAY. PLAYING TOWARD MODEL BIASES...ONCE
AGAIN WENT BELOW THE MODEL BLEND. HOWEVER...CENTRAL VA MAY BE ABLE
TO BREAK INTO THE WARM SECTOR. AND LAPSE RATES ALOFT WILL BE FAIRLY
STEEP ACROSS THE ENTIRE AREA. HAVE SLIGHT CHANCE OF THUNDER NORTH
AND CHANCE SOUTH. WITH MODERATE DEEP LAYER SHEAR...THERE COULD BE
SOME STRONGER STORMS TOWARD CENTRAL VA...AND THIS AREA IS INCLUDED
IN SPC DAY 3 MARGINAL RISK. MODEL CONSENSUS ATTM IS FOR LOW TO BE
PULLING AWAY LATE SUNDAY NIGHT.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
LATEST GUIDANCE SUPPORTS THE IDEA OF THE LOW PRESSURE DEPARTING
THE AREA FASTER ON MONDAY...THOUGH PASSING TROUGH AND NORTHEAST
FLOW MAY KEEP A FEW SHOWERS GOING ACROSS THE REGION. THE FLOW MAY
TURN NORTHWEST IN THE AFTERNOON WHICH COULD ALLOW CLOUDS TO BREAK
AND SOME SUN TO REACH THE GROUND...AND ALLOW TEMPS TO NEAR 70.
GUIDANCE MOSTLY AGREES ON A DRIER TREND MONDAY NIGHT BUT TUESDAY
ONWARD IS STILL QUESTIONABLE WITH THE EC STILL SHOWING A WAVE
MOVING NORTHEAST FROM THE GULF...WHILE THE GFS IS MUCH SLOWER
BRINGING A WAVE UP. BOTH MODELS DO SHOW THE WAVE OFF THE SOUTHEAST
COAST WEDNESDAY BUT ARE SHUNTED EAST OF THE PREVIOUS EC
RUNS...KEEPING US MOSTLY DRY. GFS AND EC BOTH HAVE ANOTHER FRONT
SLIDE IN FROM THE NORTHWEST ON THURSDAY WITH MUCH COOLER AIR
BEHIND IT. GFS IS FAIRLY DRY WHILE EC GENERATES A FAIR AMOUNT OF
SHOWERS. OVERALL IT WILL BE A COOLER THAN NORMAL WEEK WITH HIGHS
MOSTLY NEAR OR BELOW 70.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
WIDESPREAD IFR/LIFR CONDITIONS THIS MORNING. MOST GUIDANCE HAS
CIGS LIFTING TO MVFR BY THIS AFTERNOON...BUT LOW CONFIDENCE ON HOW
HIGH. WL STICK WITH PERSISTENCE FOR NOW. COULD BE A FEW SHOWERS LATE
THIS AFTERNOON...BUT COVERAGE WILL PRECLUDE TAF MENTION FOR NOW.
OTHERWISE EXPECT PREDOMINANTLY DZ.

CONDITIONS WILL DETERIORATE AGAIN TONIGHT WITH WIDESPREAD IFR
EXPECTED WITH LOW CIGS...DZ...AND FOG. SHOULD BE SOME IMPROVEMENT ON
SATURDAY WITH PERHAPS VFR DURING THE MIDDAY. BROAD AREA OF
RAIN...PERHAPS MODERATE...WILL MOVE ACROSS THE AREA SATURDAY NIGHT
WITH SUB-VFR CONDITIONS LIKELY. SHOWERS CONTINUE SUNDAY INTO SUNDAY
NIGHT WITH THUNDER POSSIBLE...ESPECIALLY CHO. TEMPORAL RESOLUTION OF
CIGS/VSBYS BECOMES LESS CERTAIN DURING THIS TIME.

CIGS AND VIS LIKELY TO IMPROVE GRADUALLY MONDAY WITH VFR PROBABLE
BY TUESDAY.

&&

.MARINE...
ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING 5-
10 KT WITH OCCASIONAL INCREASES TO 15 KT. LIGHT FOG AND DZ WILL
CONTINUE AT TIMES. NEXT ROUND OF RAIN AND ASSOCIATED LLJ IS A LITTLE
QUICKER NOW AND SCA CONDITIONS MAY BE REACHED AS EARLY AS SATURDAY
NIGHT. THIS POSSIBILITY WILL REMAIN SUNDAY INTO SUNDAY NIGHT...
ALTHOUGH PERHAPS NOT CONTINUOUSLY. THUNDERSTORMS WILL ALSO BE
POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA CONDITIONS REMAIN
POSSIBLE WITH LOW PRESSURE PASSING ON MONDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES AT OR BELOW A HALF-FOOT ABV ASTRO NORMS ATTM. AT
THAT DEPARTURE...NO ISSUES ARE ANTICIPATED WITH THE UPCOMING TIDE
CYCLE. WILL NEED TO CONTINUE WATCHING ANOMALIES AS WITH THE
CONTINUED NORTHEAST FLOW...WATER LEVELS MAY RE-BUILD IN THE BAY
AND POTOMAC.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM
NEAR TERM...HTS/ADS
SHORT TERM...ADS
LONG TERM...RCM
AVIATION...HTS/ADS/RCM
MARINE...ADS/RCM
TIDES/COASTAL FLOODING...HTS/RCM





000
FXUS61 KLWX 290801
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
401 AM EDT FRI APR 29 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH TODAY. ANOTHER WEAK
WAVE OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY. THE BOUNDARY
WILL DROP SOUTH SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE
MID-ATLANTIC SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH
LATER NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVE LULL IN ACTIVITY ACROSS THE AREA THIS MORNING...WITH ONLY
A FEW SHOWERS EMBEDDED WITHIN THE DZ AND LIGHT FOG. WEDGE OF HIGH
PRESSURE EVIDENT EAST OF THE MTNS IN VA...WITH MAIN FRONT STILL
DRAPED ACROSS NC. SUBTLE SHORTWAVE TROUGH OVER WVA MAY SPARK A FEW
SHOWERS THIS MORNING ACROSS THE NORTHERN HALF OF THE
AREA...OTHERWISE PRECIP SHOULD LARGELY BE DZ.

GUIDANCE HINTING THAT CLOUDS MAY ERODE SOME BY THIS AFTERNOON ACROSS
SOUTHWESTERN PORTIONS OF THE AREA. PERHAPS NOT CLEARING...BUT AT
LEAST LIFTING. ELSEWHERE EXPECT LOW CLOUDS TO HOLD FIRM. SHOULD BE
ENOUGH DRYING TO CUT BACK ON DZ/FOG THOUGH. THIS COULD LEAD TO A
GRADIENT IN TEMPERATURES...WITH COOLEST TO THE NE. HAVE SHADED A
LITTLE BELOW MODEL BLEND.

VORT MAX CURRENTLY OVER LAKE MICHIGAN WILL PASS TO THE NORTH LATE
THIS AFTERNOON. THIS WILL BRING A RENEWED CHANCE OF LIGHT SHOWERS
MOVING FROM NW TO SE ACROSS THE REGION. HAVE KEPT POPS AT CHANCE
GIVEN EXPECTED SCATTERED/LIGHT NATURE. THIS WILL ALSO SERVE TO GIVE
THE FRONTAL ZONE A NUDGE TO THE SOUTH AND DRY OUT THE
ATMOSPHERE...EXCEPT AT THE LOW LEVELS. WITH A CONTINUED OVERRUNNING
FLOW...HAVE KEPT PATCHY DZ WORDING IN THE FORECAST LATE TONIGHT.
LIGHT FOG POSSIBLE ONCE AGAIN TOO. SAME TREND...ONLY SMALL DROP IN
TEMPS OVERNIGHT.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE TREND FOR THE WEEKEND CONTINUES TO BE LESS DRY. NOT A TOTAL
WASHOUT...BUT PROLONGED BREAKS WILL BE SPARSE ONCE ISENTROPIC LIFT
BEGINS AHEAD OF LOW PRESSURE OVER THE PLAINS. RAIN COULD ARRIVE IN
THE MOUNTAINS SATURDAY MORNING...AND AT LEAST A CHANCE OF IT
SPREADING EAST DURING THE AFTERNOON. STILL SOME TIMING DIFFERENCES.
BUT BROUGHT POPS TO CATEGORICAL SATURDAY NIGHT AND WORDED AS
RAIN...LOOKS LIKE A GOOD SLUG OF MOISTURE...AND PERHAPS BE MODERATE
AT TIMES. TRENDED MAX T ON SATURDAY DOWN A LITTLE.

SFC LOW AND OPENING UPPER WAVE WILL BE APPROACHING THE OHIO VALLEY
SUNDAY INTO SUNDAY NIGHT. CONTINUED LIFT AND MOISTURE ADVECTION WILL
MEAN HIGH CHANCES OF SHOWERS CONTINUING. BIGGEST UNCERTAINTY IS WHAT
HAPPENS TO WEDGE FRONT ON SUNDAY. PLAYING TOWARD MODEL BIASES...ONCE
AGAIN WENT BELOW THE MODEL BLEND. HOWEVER...CENTRAL VA MAY BE ABLE
TO BREAK INTO THE WARM SECTOR. AND LAPSE RATES ALOFT WILL BE FAIRLY
STEEP ACROSS THE ENTIRE AREA. HAVE SLIGHT CHANCE OF THUNDER NORTH
AND CHANCE SOUTH. WITH MODERATE DEEP LAYER SHEAR...THERE COULD BE
SOME STRONGER STORMS TOWARD CENTRAL VA...AND THIS AREA IS INCLUDED
IN SPC DAY 3 MARGINAL RISK. MODEL CONSENSUS ATTM IS FOR LOW TO BE
PULLING AWAY LATE SUNDAY NIGHT.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
LATEST GUIDANCE SUPPORTS THE IDEA OF THE LOW PRESSURE DEPARTING
THE AREA FASTER ON MONDAY...THOUGH PASSING TROUGH AND NORTHEAST
FLOW MAY KEEP A FEW SHOWERS GOING ACROSS THE REGION. THE FLOW MAY
TURN NORTHWEST IN THE AFTERNOON WHICH COULD ALLOW CLOUDS TO BREAK
AND SOME SUN TO REACH THE GROUND...AND ALLOW TEMPS TO NEAR 70.
GUIDANCE MOSTLY AGREES ON A DRIER TREND MONDAY NIGHT BUT TUESDAY
ONWARD IS STILL QUESTIONABLE WITH THE EC STILL SHOWING A WAVE
MOVING NORTHEAST FROM THE GULF...WHILE THE GFS IS MUCH SLOWER
BRINGING A WAVE UP. BOTH MODELS DO SHOW THE WAVE OFF THE SOUTHEAST
COAST WEDNESDAY BUT ARE SHUNTED EAST OF THE PREVIOUS EC
RUNS...KEEPING US MOSTLY DRY. GFS AND EC BOTH HAVE ANOTHER FRONT
SLIDE IN FROM THE NORTHWEST ON THURSDAY WITH MUCH COOLER AIR
BEHIND IT. GFS IS FAIRLY DRY WHILE EC GENERATES A FAIR AMOUNT OF
SHOWERS. OVERALL IT WILL BE A COOLER THAN NORMAL WEEK WITH HIGHS
MOSTLY NEAR OR BELOW 70.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
WIDESPREAD IFR/LIFR CONDITIONS THIS MORNING. THESE SHOULD CONTINUE
THROUGH DAYBREAK. MOST GUIDANCE HAS CIGS LIFTING TO MVFR BY THIS
AFTERNOON...BUT LOW CONFIDENCE ON HOW HIGH. COULD BE A FEW SHOWERS
EARLY THIS MORNING AND AGAIN LATE THIS AFTERNOON...BUT COVERAGE WILL
PRECLUDE TAF MENTION FOR NOW. OTHERWISE EXPECT PREDOMINANTLY DZ.

CONDITIONS WILL DETERIORATE AGAIN TONIGHT WITH WIDESPREAD IFR
EXPECTED WITH LOW CIGS...DZ...AND FOG. SHOULD BE SOME IMPROVEMENT ON
SATURDAY WITH PERHAPS VFR DURING THE MIDDAY. BROAD AREA OF
RAIN...PERHAPS MODERATE...WILL MOVE ACROSS THE AREA SATURDAY NIGHT
WITH SUB-VFR CONDITIONS LIKELY. SHOWERS CONTINUE SUNDAY INTO SUNDAY
NIGHT WITH THUNDER POSSIBLE...ESPECIALLY CHO. TEMPORAL RESOLUTION OF
CIGS/VSBYS BECOMES LESS CERTAIN DURING THIS TIME.

CIGS AND VIS LIKELY TO IMPROVE GRADUALLY MONDAY WITH VFR PROBABLE
BY TUESDAY.

&&

.MARINE...
ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING 5-
10 KT WITH OCCASIONAL INCREASES TO 15 KT. LIGHT FOG AND DZ WILL
CONTINUE AT TIMES. NEXT ROUND OF RAIN AND ASSOCIATED LLJ IS A LITTLE
QUICKER NOW AND SCA CONDITIONS MAY BE REACHED AS EARLY AS SATURDAY
NIGHT. THIS POSSIBILITY WILL REMAIN SUNDAY INTO SUNDAY
NIGHT...ALTHOUGH PERHAPS NOT CONTINUOUSLY. THUNDERSTORMS WILL ALSO
BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA CONDITIONS REMAIN
POSSIBLE WITH LOW PRESSURE PASSING ON MONDAY.

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES HAVE CONTINUED TO DECLINE OVERNIGHT...AND RIGHT
NOW WE DO NOT EXPECT ANY FLOODING WITH THE MORNING CYCLE. WILL
NEED TO CONTINUE WATCHING ANOMALIES AS WITH THE CONTINUED
NORTHEAST FLOW...WATER LEVELS MAY RE-BUILD IN THE BAY AND POTOMAC.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...RCM
AVIATION...ADS/RCM
MARINE...ADS/RCM
TIDES/COASTAL FLOODING...RCM





000
FXUS61 KLWX 290047
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
847 PM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP  AS FRONTS AND LOW PRESS SYSTEM
MOVES THROUGH THE MID- ATLANTIC BRINGING SHOWERS INTO THE
REGION... MAINLY SUN INTO MON NIGHT.FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A NEARLY STATIONARY BOUNDARY REMAINS DRAPED OVER THE ALLEGHENY
HIGHLANDS INTO SOUTHERN VIRGINIA AND NORTHEASTERN NORTH CAROLINA.
THE BOUNDARY WILL REMAIN NEARLY STATIONARY THROUGH TONIGHT...WHICH
MEANS THAT COOL NORTHEAST WINDS WILL PERSIST OVER THE AREA. MIN
TEMPS WILL RANGE FROM THE LOWER TO MIDDLE 40S ALONG THE MASON-
DIXON LINE TO LOWER AND MIDDLE 50S IN THE CENTRAL SHENANDOAH
VALLEY.

AN ONSHORE FLOW WILL CONTINUE TO CAUSE LOW-LEVEL MOISTURE TO BE
TRAPPED UNDERNEATH THE SUBSIDENCE INVERSION...RESULTING IN LOW
CLOUDS ALONG WITH AREAS OF FOG. WARM AND MOIST AIR WILL CONTINUE
TO OVERRUN THE COOL AIR IN PLACE...RESULTING IN DRIZZLE AND
PERHAPS EVEN LIGHT RAIN. A PERIOD OF STEADIER RAIN IS LIKELY THIS
EVENING FOR MOST AREAS THIS EVENING. THIS IS BECAUSE OF SHOWERS
AND THUNDERSTORMS THAT POPPED UP TO OUR WEST IN THE WARM AIR THIS
AFTERNOON. THE ACTIVITY IS PASSING THROUGH THIS EVENING...AND IT
IS WEAKENING DUE TO THE COOLER AIR BUT STILL PRODUCING PERIODS OF
STEADIER RAIN.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
ZONAL H5 FLOW/ELY SFC FLOW WL CONT INTO FRI...AS S/WV ENERGY
TRACKS EWD N OF CWFA. CHC TO LIKELY POPS PREVAIL...HIEST ACROSS
THE NORTHERN HALF OF THE CWA. DONT BELIEVE PCPN WL BE ALL THAT
MEANINGFUL.

WL HV WEAK RDGG IN THE WAKE OF THE S/WV FRI NGT. THIS IS THE BEST
CHC AT A DRY PD FOR THIS FCST CYCLE. AFTER LINGERING EVNG POPS...
PRESERVED 10 POPS/PATCHY DZ WORDING FOR THE OVNGT HRS.

WAA/ISENT LIFT IMPRV SAT-SAT NGT AS AN AMPLIFIED TROF AXIS IN THE
SRN PLAINS EJECTS TWD CWFA. POPS WL BE STAIR-STEPPED UPWD AS THIS
FORCING APPROACHES. LKLY SHRA BY SAT NGT. IT CUD BE ERLR PENDING ANY
TIMING ADJUSTMENTS IN LATER GDNC RUNS.

CWFA WL REMAIN ON THE COOL SIDE OF THE STALLED BNDRY THRUT THIS PD.
TEMPS REFLECT A MDL BLEND/PERSISTENCE TYPE FCST...WHICH CAPTURE THE
LACK OF DIURNAL RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
LOW PRESS OVER THE OHIO VALLEY AND ITS ASSOCIATED WARM FRONT WILL
BE LIFTING NORTH ON SUN... MOVING ACROSS THE REGION AND BRINGING
SHOWERS TO OUR CWA. THE LOW PRESS WILL TRACK EAST AND MOVE OFF OF
THE MID-ATLANTIC COAST SUN NIGHT INTO EARLY MON... WITH ITS
ASSOCIATED COLD FRONT. GUIDANCE DIFFERS ON TUE TO WED NIGHT
CONDITIONS... WITH GFS BEING DRIER... BUT BRINGING SHOWERS DUE TO
A SHORTWAVE TROUGH ON TUE... WHILE EURO KEEPS A BOUNDARY STALLING
TO OUR SE AND WAVES OF LOW PRESS MOVING THROUGH IT... THEREFORE
KEEPING MAINLY THE SOUTHERN PART OF OUR CWA WITH HIGHER CHANCES OF
PRECIP. COLD FRONT APPROACHES ON THU. TEMPS WILL BE NEAR OR
SLIGHTLY BELOW NORMAL.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
IFR CONDITIONS ALONG WITH PERIODS OF DRIZZLE AND EVEN SOME RAIN AT
TIMES WILL CONTINUE TONIGHT. MVFR CONDITIONS STILL PERSIST
ACROSS KBWI AND KMTN THIS EVENING DUE TO SOME DRIER AIR.
HOWEVER...IFR CONDITIONS ARE EXPECTED TO DEVELOP ACROSS THESE
AREAS OVERNIGHT. THE IFR CONDITIONS WILL PERSIST THROUGH MOST OF
FRIDAY...BUT MAY LIFT TO MVFR LEVELS SOMETIME FRIDAY AFTERNOON
INTO EARLY FRIDAY EVENING. MORE IFR CONDITIONS ARE EXPECTED
FRIDAY NIGHT. PERIODS OF DRIZZLE AND POSSIBLE LIGHT RAIN ARE
POSSIBLE DURING THIS TIME. FRI NGT MAY END UP BEING THE DRIEST
PART OF THIS FCST...BUT THAT MAY ALSO MEAN THE FOG CUD BE THE
DENSEST. BETTER OPPORTUNITY FOR WIDESPREAD RAIN WL OVERSPREAD THE
TERMINALS DURING THE AFTN- EVE SAT.

SUB-VFR CONDITIONS POSSIBLE SATURDAY NIGHT INTO MONDAY MORNING AS
A BOUNDARY REMAINS STALLED NEAR THE AREA AND LOW PRESSURE TRACKS
ALONG IT. THE BOUNDARY WILL PUSH WELL TO OUR SOUTH EARLY NEXT WEEK
AND VFR CONDITIONS MAY RETURN..

&&

.MARINE...
ELY FLOW 10-15 KT ATTM...WHICH WL BE THE MAIN STORY FOR THE NEXT CPL
OF DAYS. DO NOT ANTICIPATE ANY SCA CONDS THRU SAT.

SUB-SCA CONDITIONS EXPECTED DURING THIS
PERIOD AS WINDS WILL BE BELOW CRITERIA. SHOWERS EXPECTED MAINLY SUN
INTO MON NIGHT.

&&

.TIDES/COASTAL FLOODING...
WATER ANOMALIES HAVE BEEN SLOWLY FALLING AND AS HIDE TIDE AS
PASSED...WATER LEVELS HAVE FALLEN BELOW FLOOD STAGE. THE HIDE TIDE
CYCLE THIS EVENING IS NOT EXPECTED TO CAUSE ANY FLOODING
CONCERNS...BUT FRIDAY MORNINGS CYCLE MAY ONCE AGAIN CAUSE MINOR
FLOODING AT ANNAPOLIS .

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...BJL/HTS
SHORT TERM...HTS
LONG TERM...IMR
AVIATION...BJL/IMR/HTS
MARINE...BJL/IMR/HTS
TIDES/COASTAL FLOODING...MJM/BJL





000
FXUS61 KLWX 290047
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
847 PM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP  AS FRONTS AND LOW PRESS SYSTEM
MOVES THROUGH THE MID- ATLANTIC BRINGING SHOWERS INTO THE
REGION... MAINLY SUN INTO MON NIGHT.FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A NEARLY STATIONARY BOUNDARY REMAINS DRAPED OVER THE ALLEGHENY
HIGHLANDS INTO SOUTHERN VIRGINIA AND NORTHEASTERN NORTH CAROLINA.
THE BOUNDARY WILL REMAIN NEARLY STATIONARY THROUGH TONIGHT...WHICH
MEANS THAT COOL NORTHEAST WINDS WILL PERSIST OVER THE AREA. MIN
TEMPS WILL RANGE FROM THE LOWER TO MIDDLE 40S ALONG THE MASON-
DIXON LINE TO LOWER AND MIDDLE 50S IN THE CENTRAL SHENANDOAH
VALLEY.

AN ONSHORE FLOW WILL CONTINUE TO CAUSE LOW-LEVEL MOISTURE TO BE
TRAPPED UNDERNEATH THE SUBSIDENCE INVERSION...RESULTING IN LOW
CLOUDS ALONG WITH AREAS OF FOG. WARM AND MOIST AIR WILL CONTINUE
TO OVERRUN THE COOL AIR IN PLACE...RESULTING IN DRIZZLE AND
PERHAPS EVEN LIGHT RAIN. A PERIOD OF STEADIER RAIN IS LIKELY THIS
EVENING FOR MOST AREAS THIS EVENING. THIS IS BECAUSE OF SHOWERS
AND THUNDERSTORMS THAT POPPED UP TO OUR WEST IN THE WARM AIR THIS
AFTERNOON. THE ACTIVITY IS PASSING THROUGH THIS EVENING...AND IT
IS WEAKENING DUE TO THE COOLER AIR BUT STILL PRODUCING PERIODS OF
STEADIER RAIN.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
ZONAL H5 FLOW/ELY SFC FLOW WL CONT INTO FRI...AS S/WV ENERGY
TRACKS EWD N OF CWFA. CHC TO LIKELY POPS PREVAIL...HIEST ACROSS
THE NORTHERN HALF OF THE CWA. DONT BELIEVE PCPN WL BE ALL THAT
MEANINGFUL.

WL HV WEAK RDGG IN THE WAKE OF THE S/WV FRI NGT. THIS IS THE BEST
CHC AT A DRY PD FOR THIS FCST CYCLE. AFTER LINGERING EVNG POPS...
PRESERVED 10 POPS/PATCHY DZ WORDING FOR THE OVNGT HRS.

WAA/ISENT LIFT IMPRV SAT-SAT NGT AS AN AMPLIFIED TROF AXIS IN THE
SRN PLAINS EJECTS TWD CWFA. POPS WL BE STAIR-STEPPED UPWD AS THIS
FORCING APPROACHES. LKLY SHRA BY SAT NGT. IT CUD BE ERLR PENDING ANY
TIMING ADJUSTMENTS IN LATER GDNC RUNS.

CWFA WL REMAIN ON THE COOL SIDE OF THE STALLED BNDRY THRUT THIS PD.
TEMPS REFLECT A MDL BLEND/PERSISTENCE TYPE FCST...WHICH CAPTURE THE
LACK OF DIURNAL RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
LOW PRESS OVER THE OHIO VALLEY AND ITS ASSOCIATED WARM FRONT WILL
BE LIFTING NORTH ON SUN... MOVING ACROSS THE REGION AND BRINGING
SHOWERS TO OUR CWA. THE LOW PRESS WILL TRACK EAST AND MOVE OFF OF
THE MID-ATLANTIC COAST SUN NIGHT INTO EARLY MON... WITH ITS
ASSOCIATED COLD FRONT. GUIDANCE DIFFERS ON TUE TO WED NIGHT
CONDITIONS... WITH GFS BEING DRIER... BUT BRINGING SHOWERS DUE TO
A SHORTWAVE TROUGH ON TUE... WHILE EURO KEEPS A BOUNDARY STALLING
TO OUR SE AND WAVES OF LOW PRESS MOVING THROUGH IT... THEREFORE
KEEPING MAINLY THE SOUTHERN PART OF OUR CWA WITH HIGHER CHANCES OF
PRECIP. COLD FRONT APPROACHES ON THU. TEMPS WILL BE NEAR OR
SLIGHTLY BELOW NORMAL.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
IFR CONDITIONS ALONG WITH PERIODS OF DRIZZLE AND EVEN SOME RAIN AT
TIMES WILL CONTINUE TONIGHT. MVFR CONDITIONS STILL PERSIST
ACROSS KBWI AND KMTN THIS EVENING DUE TO SOME DRIER AIR.
HOWEVER...IFR CONDITIONS ARE EXPECTED TO DEVELOP ACROSS THESE
AREAS OVERNIGHT. THE IFR CONDITIONS WILL PERSIST THROUGH MOST OF
FRIDAY...BUT MAY LIFT TO MVFR LEVELS SOMETIME FRIDAY AFTERNOON
INTO EARLY FRIDAY EVENING. MORE IFR CONDITIONS ARE EXPECTED
FRIDAY NIGHT. PERIODS OF DRIZZLE AND POSSIBLE LIGHT RAIN ARE
POSSIBLE DURING THIS TIME. FRI NGT MAY END UP BEING THE DRIEST
PART OF THIS FCST...BUT THAT MAY ALSO MEAN THE FOG CUD BE THE
DENSEST. BETTER OPPORTUNITY FOR WIDESPREAD RAIN WL OVERSPREAD THE
TERMINALS DURING THE AFTN- EVE SAT.

SUB-VFR CONDITIONS POSSIBLE SATURDAY NIGHT INTO MONDAY MORNING AS
A BOUNDARY REMAINS STALLED NEAR THE AREA AND LOW PRESSURE TRACKS
ALONG IT. THE BOUNDARY WILL PUSH WELL TO OUR SOUTH EARLY NEXT WEEK
AND VFR CONDITIONS MAY RETURN..

&&

.MARINE...
ELY FLOW 10-15 KT ATTM...WHICH WL BE THE MAIN STORY FOR THE NEXT CPL
OF DAYS. DO NOT ANTICIPATE ANY SCA CONDS THRU SAT.

SUB-SCA CONDITIONS EXPECTED DURING THIS
PERIOD AS WINDS WILL BE BELOW CRITERIA. SHOWERS EXPECTED MAINLY SUN
INTO MON NIGHT.

&&

.TIDES/COASTAL FLOODING...
WATER ANOMALIES HAVE BEEN SLOWLY FALLING AND AS HIDE TIDE AS
PASSED...WATER LEVELS HAVE FALLEN BELOW FLOOD STAGE. THE HIDE TIDE
CYCLE THIS EVENING IS NOT EXPECTED TO CAUSE ANY FLOODING
CONCERNS...BUT FRIDAY MORNINGS CYCLE MAY ONCE AGAIN CAUSE MINOR
FLOODING AT ANNAPOLIS .

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...BJL/HTS
SHORT TERM...HTS
LONG TERM...IMR
AVIATION...BJL/IMR/HTS
MARINE...BJL/IMR/HTS
TIDES/COASTAL FLOODING...MJM/BJL





000
FXUS61 KLWX 281903
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
303 PM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
THE MAIN BATCH OF PCPN HAS MOVED N/NE OF CWFA. IN THE CLEARING IN
ITS WAKE...SCT TSRA HV DVLPD. THESE STORMS FORMED IN A WARM/UNSTBL
AMS...BUT ARE ENTERING A MUCH MORE HOSTILE ENVIRONMENT. THEREFORE
ANTICIPATE THE THUNDER ASPECT TO ERODE...BUT SHREA SHUD BE ABLE TO
TRACK ACRS CENTRAL VA. HV MAINTAINED CHC POPS MINIMUM...AND GRDLY
NUDGE THEM UPWD INTO THE ELY EVNG.

HGTS WL BE RATHER ZONAL AND STABLE OVNGT...W/ ANY PVA GNLY N OF
CWFA. THERES NOT MUCH TO DRIVE ADDTL PCPN PRODUCTION...OTHER THAN
THE OVERRUNNING PTTN IN PLACE. MEANWHILE...LLVLS REMAIN MOIST. WL
HOLD ONTO CHC POPS BUT SWITCH TO A RADZ SOLN.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
ZONAL H5 FLOW/ELY SFC FLOW WL CONT INTO FRI...AS S/WV ENERGY
TRACKS EWD N OF CWFA. CHC POPS PREVAIL...HIEST NEAR THE PA BRDR.
DONT BELIEVE PCPN WL BE ALL THAT MEANINGFUL.

WL HV WEAK RDGG IN THE WAKE OF THE S/WV FRI NGT. THIS IS THE BEST
CHC AT A DRY PD FOR THIS FCST CYCLE. AFTER LINGERING EVNG POPS...
PRESERVED 10 POPS/PATCHY DZ WORDING FOR THE OVNGT HRS.

WAA/ISENT LIFT IMPRV SAT-SAT NGT AS AN AMPLIFIED TROF AXIS IN THE
SRN PLAINS EJECTS TWD CWFA. POPS WL BE STAIR-STEPPED UPWD AS THIS
FORCING APPROACHES. LKLY SHRA BY SAT NGT. IT CUD BE ERLR PENDING ANY
TIMING ADJUSTMENTS IN LATER GDNC RUNS.

CWFA WL REMAIN ON THE COOL SIDE OF THE STALLED BNDRY THRUT THIS PD.
TEMPS REFLECT A MDL BLEND/PERSISTENCE TYPE FCST...WHICH CAPTURE THE
LACK OF DIURNAL RANGE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
LOW PRESS OVER THE OHIO VALLEY AND ITS ASSOCIATED WARM FRONT WILL
BE LIFTING NORTH ON SUN... MOVING ACROSS THE REGION AND BRINGING
SHOWERS TO OUR CWA. THE LOW PRESS WILL TRACK EAST AND MOVE OFF OF
THE MID-ATLANTIC COAST SUN NIGHT INTO EARLY MON... WITH ITS
ASSOCIATED COLD FRONT. GUIDANCE DIFFERS ON TUE TO WED NIGHT
CONDITIONS... WITH GFS BEING DRIER... BUT BRINGING SHOWERS DUE TO
A SHORTWAVE TROUGH ON TUE... WHILE EURO KEEPS A BOUNDARY STALLING
TO OUR SE AND WAVES OF LOW PRESS MOVING THROUGH IT... THEREFORE
KEEPING MAINLY THE SOUTHERN PART OF OUR CWA WITH HIGHER CHANCES OF
PRECIP. COLD FRONT APPROACHES ON THU. TEMPS WILL BE NEAR OR
SLIGHTLY BELOW NORMAL.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
FLGT CONDS SHUD REMAIN FAIRLY CONSISTENT THRU SAT-- MAINLY MVFR BUT
PDS OF IFR...SPCLY AT NGT. PCPN POTL REMAINS HIT-OR-MISS. FRI NGT
MAY END UP BEING THE DRIEST PART OF THIS FCST...BUT THAT MAY ALSO
MEAN THE FOG CUD BE THE DENSEST. BETTER OPPORTUNITY FOR RAIN WL
OVERSPREAD THE TERMINALS DURING THE AFTN-EVE SAT.

SUB-VFR CONDITIONS POSSIBLE DURING THIS
PERIOD AS FRONTS AND LOW PRESS SYSTEM MOVES THROUGH THE MID-ATLANTIC
BRINGING SHOWERS INTO THE REGION... MAINLY SUN INTO MON NIGHT.

&&

.MARINE...
ELY FLOW 10-15 KT ATTM...WHICH WL BE THE MAIN STORY FOR THE NEXT CPL
OF DAYS. DO NOT ANTICIPATE ANY SCA CONDS THRU SAT.

SUB-SCA CONDITIONS EXPECTED DURING THIS
PERIOD AS WINDS WILL BE BELOW CRITERIA. SHOWERS EXPECTED MAINLY SUN
INTO MON NIGHT.

&&

.TIDES/COASTAL FLOODING...
WATER ANOMALIES HAVE BEEN SLOWLY FALLING AND AS HIDE TIDE AS
PASSED...WATER LEVELS HAVE FALLEN BELOW FLOOD STAGE. THE HIDE TIDE
CYCLE THIS EVENING IS NOT EXPECTED TO CAUSE ANY FLOODING
CONCERNS...BUT FRIDAY MORNINGS CYCLE MAY ONCE AGAIN CAUSE MINOR
FLOODING AT ANNAPOLIS.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...IMR
AVIATION...IMR/HTS
MARINE...IMR/HTS
TIDES/COASTAL FLOODING...MJM





000
FXUS61 KLWX 281420
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1020 AM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /THROUGH TONIGHT/...
LTL SYNOP CHG TO FCST THIS MRNG. STALLED SFC BOUNDARY STILL
LOCATED NEAR NC...SNAKING TO VERTICALLY STACKED LOW PRESSURE OVER
IOWA. MARITIME FLOW DOMINATES WITH PLENTY OF CLOUD COVER. A SWATH
OF SHRA STRETCHES FM THE PTMC HIGHLANDS ACRS METRO DC TO SRN MD.
BEHIND THIS ACTIVITY...FAIRLY SUBSTANTIAL DRY SLOT IS NOTED IN
WATER VAPOR IMAGERY. THIS WILL LIKELY LEAD TO RAPIDLY DIMINISHING
COVERAGE OF SHOWERS DURING THE AFTERNOON. HOWEVER...WITH
ADDITIONAL WEAK SHORTWAVE ENERGY AND CONTINUED OVERRUNING...SOME
LIGHT SHOWERS OR SPRINKLES WILL REMAIN POSSIBLE. IN ADDITION...BL
HEATING WILL TAKE PLACE S/W OF THE CWA IN AN ENVIRONMENT OF
MODERATE DEEP LAYER SHEAR. SOME OF THIS THUNDERSTORM ACTIVITY MAY
PUSH INTO THE POTOMAC HIGHLANDS AND ALONG THE SOUTHERN CWA BORDER
THIS AFTERNOON.

HV MADE TIMING ADJUSTMENTS IN DATABASE TO ACCNT FOR THIS THINKING
AND LTST RADAR TRENDS. ON THE WHOLE...PREV THOUGHT PROCESS REMAINS
VALID. CONSIDERING CURRENT RAFL AND LTST LAMP...HV ADJUSTED TEMPS
DOWN ARND MUCH OF MD AND ADJACENT VA. AM NOT TOUCHING CENTRAL
FOOTHILLS/CENTRAL SHEN VLY AS TEMPS CUD JUMP THERE QUITE QUICKLY.

THE OPENED LOW WILL BE NEAR PA TONIGHT. THUS THE HIGHEST POPS
WILL BE IN THE NORTHERN CWA. LOW LEVELS WILL BE SATURATED ACROSS
THE ENTIRE AREA THOUGH...SO HAVE INTRODUCED PATCHY DRIZZLE AND FOG
TO THE FORECAST. LOWS WILL RANGE FROM THE MID 40S TO MID 50S.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
WEAK SFC LOW WILL STILL BE NEAR THE AREA ON FRIDAY WITH CAD WEDGE
FRONT NEARLY UNCHANGED. HOWEVER...TREND IN 00Z GUIDANCE IS TO KEEP
SHORTWAVE TROUGH FARTHER TO THE NORTH. SO SEE LITTLE REASON TO
CHANGE POPS...CAPPING IN THE CHANCE CATEGORY WITH HIGHEST NEAR PA
BORDER. THE LOW MAY DRAW SOME WARMER AIR INTO CENTRAL VA...BUT
HIGHS WILL REMAIN IN THE MID 50S NEAR THE PA BORDER. ANY CHANCE OF
MEASURABLE PRECIP WILL END FRIDAY EVENING AS THE DEPARTING LOW
DRAGS THE FRONT SOUTH AND HIGH PRESSURE BUILDS. THERE WILL STILL
BE LOW LEVEL OVERRUNNING...SO COULD SEE SOME LINGERING DRIZZLE.

THE FIRST HALF OF SATURDAY SHOULD BE DRY AS SHORTWAVE RIDGING
MOVES OVERHEAD. HOWEVER...THE TREND HAS BEEN FASTER WITH
ISENTROPIC LIFT AHEAD OF THE NEXT LOW OVER THE PLAINS...WITH RAIN
POSSIBLE ACROSS WESTERN AREAS BY AFTERNOON AND ACROSS MOST OF THE
AREA OVERNIGHT. HIGHS MAY GET A BOOST FROM MIDDAY SUN
BREAKS...POTENTIALLY REACHING THE 60S IN MOST AREAS.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE THROUGH MONDAY IS IN REASONABLE...IF ROUGH...AGREEMENT.
THE STATIONARY BOUNDARY TO OUR SOUTH WILL START TO LIFT NORTH AS
ANOTHER WAVE OF LOW PRESSURE TRACKS EASTWARD FROM THE CENTRAL
PLAINS AND OHIO VALLEY. THE WEDGE OF COOLER AIR WILL BE HARD TO
DISLODGE AND WHILE SOME MILDER AIR MAY TRY TO ENTER THE CWA LATE
SUNDAY OR MONDAY...MOST OF THE REGION WILL PROBABLY STAY ON THE
COOL SIDE OF THE BOUNDARY. AFTER THE TROUGH AXIS ALOFT PASSES
THROUGH LATE MONDAY...GUIDANCE DIFFERS IN THE POTENTIAL FOR
ANOTHER WAVE TO MOVE NORTHEASTWARD UP THE COAST...SO WE MAINTAIN A
CHANCE OF SHOWERS. OTHER THAN THE BRIEF CHANCE OF A WARM
INTERLUDE WITH THE PASSING WAVE LATE SUNDAY INTO
MONDAY...TEMPERATURES WILL BE ON THE COOL SIDE OF NORMAL.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
OVERALL THEME OF FORECAST DOES NOT CHANGE APPRECIABLY THROUGH
FRIDAY NIGHT AS THE REGION WILL REMAIN ENTRENCHED IN MARITIME
FLOW/CAD WEDGE. MAIN ISSUE WILL BE TIMING IN IFR RESTRICTION (MORE
LIKELY OVERNIGHT THAN DURING DAY). FOG...SHOWERS...AND DRIZZLE
COULD REDUCE VSBY AT TIMES...BUT CLOUDS WILL BE THE BIGGER ISSUE.
BEST CHANCE AT POTENTIALLY MODERATE RAIN WILL CROSS THE AREA
DURING THE MID MORNING HOURS (QUICKER THAN PREVIOUS FORECASTS).
ANY AFTERNOON THUNDERSTORMS SHOULD STAY SOUTH OF CHO. COULD SEE A
RISE TO SOLID VFR CONDITIONS ON SATURDAY...BUT ADDITIONAL RAIN AND
LOW CLOUDS WILL ARRIVE SATURDAY NIGHT AND CONTINUE THROUGH MONDAY
IF NOT LONGER.

&&

.MARINE...
ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING
5- 10 KT WITH OCCASIONAL INCREASES TO 15 KT. SOME GUIDANCE
INDICATES PERIODIC FLIRTING WITH SCA-LEVEL GUSTS THIS
AFTERNOON...BUT LACK OF CONSISTENT SIGNAL PRECLUDES A HEADLINE FOR
NOW. SAME GOES FOR FRIDAY AFTERNOON. WINDS MAY TURN MORE TO THE SE
SATURDAY NIGHT BUT REMAIN SUB-SCA. BETTER CHANCE OF SCA CONDITIONS
SUNDAY AND MONDAY WITH A MORE POTENT LOW PRESSURE SYSTEM MOVING
THROUGH.

&&

.TIDES/COASTAL FLOODING...
WATER LEVELS REMAIN ANOMALOUSLY HIGH DUE TO EASTERLY FLOW ALONG
THE WESTERN SHORE OF THE CHESAPEAKE BAY AND PORTIONS OF THE TIDAL
POTOMAC. WITH MINOR FLOODING OCCURRING ALONG THE CHESAPEAKE...WILL
KEEP COASTAL FLOOD ADVISORIES IN PLACE INTO THE EARLY
AFTERNOON...EXCEPT ST MARYS COUNTY WHERE HIGH TIDE HAS PASSED AND
WATER LEVELS ARE DROPPING. HAVE ALSO ISSUED ADVISORIES ALONG THE
TIDAL POTOMAC IN THE DC METRO AREA WITH MINOR FLOODING FORECAST
THIS AFTERNOON. WITH OUR AREA EXPECTED TO REMAIN ON THE NORTH SIDE
OF THE FRONT WITH PERSISTENT EASTERLY FLOW...MINOR FLOODING WILL
REMAIN A CONCERN FOR THE NEXT SEVERAL DAYS.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
     DCZ001.
MD...COASTAL FLOOD ADVISORY UNTIL NOON EDT TODAY FOR MDZ018.
     COASTAL FLOOD ADVISORY UNTIL 3 PM EDT THIS AFTERNOON FOR
     MDZ011-014.
VA...COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
     VAZ054.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM
NEAR TERM...ADS/HTS
SHORT TERM...ADS
LONG TERM...RCM
AVIATION...ADS/RCM
MARINE...ADS/RCM
TIDES/COASTAL FLOODING...MJM/RCM





000
FXUS61 KLWX 280759
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
359 AM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /THROUGH TONIGHT/...
STALLED SFC BOUNDARY STILL LOCATED NEAR NC THIS MORNING...SNAKING
TO VERTICALLY STACKED LOW PRESSURE OVER IOWA. MARITIME FLOW
DOMINATES WITH PLENTY OF CLOUD COVER BUT VERY LITTLE PRECIP AT
THIS HOUR. THIS WILL CHANGE QUICKLY THIS MORNING AS ARC OF
CONVECTION CURRENTLY OVER THE OHIO VALLEY PUSHES EASTWARD. THIS
WARRANTED A MUCH FASTER RAMP UP IN POPS AS MOST GUIDANCE SHOWS
THIS ACTIVITY CONTINUING TO PUSH EAST ACROSS THE AREA. RECENT
LIGHTNING TRENDS SUGGEST THUNDER WILL BE ABSENT BY THE TIME IT
REACHES OUR CWA.

BEHIND THIS ACTIVITY...FAIRLY SUBSTANTIAL DRY SLOT IS NOTED IN
WATER VAPOR IMAGERY. THIS WILL LIKELY LEAD TO RAPIDLY DIMINISHING
COVERAGE OF SHOWERS DURING THE AFTERNOON. HOWEVER...WITH
ADDITIONAL WEAK SHORTWAVE ENERGY AND CONTINUED OVERRUNING...SOME
LIGHT SHOWERS OR SPRINKLES WILL REMAIN POSSIBLE. IN ADDITION...BL
HEATING WILL TAKE PLACE S/W OF THE CWA IN AN ENVIRONMENT OF
MODERATE DEEP LAYER SHEAR. SOME OF THIS THUNDERSTORM ACTIVITY MAY
PUSH INTO THE POTOMAC HIGHLANDS AND ALONG THE SOUTHERN CWA BORDER
THIS AFTERNOON. THE BULK OF THE CWA WILL BE ENTRENCHED IN THE
STABLE CAD WEDGE. HOWEVER...NOT OUT OF THE QUESTION A STRONGER
CELL ALONG THE SW BORDER COULD CONTAIN HAIL. HIGHS TODAY WILL
STRUGGLE TO THE MID 50S IN THE NORTH AND PERHAPS REACH THE MID 60S
SOUTH.

THE OPENED LOW WILL BE NEAR PA TONIGHT. THUS THE HIGHEST POPS
WILL BE IN THE NORTHERN CWA. LOW LEVELS WILL BE SATURATED ACROSS
THE ENTIRE AREA THOUGH...SO HAVE INTRODUCED PATCHY DRIZZLE AND FOG
TO THE FORECAST. LOWS WILL RANGE FROM THE MID 40S TO MID 50S.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
WEAK SFC LOW WILL STILL BE NEAR THE AREA ON FRIDAY WITH CAD WEDGE
FRONT NEARLY UNCHANGED. HOWEVER...TREND IN 00Z GUIDANCE IS TO KEEP
SHORTWAVE TROUGH FARTHER TO THE NORTH. SO SEE LITTLE REASON TO
CHANGE POPS...CAPPING IN THE CHANCE CATEGORY WITH HIGHEST NEAR PA
BORDER. THE LOW MAY DRAW SOME WARMER AIR INTO CENTRAL VA...BUT
HIGHS WILL REMAIN IN THE MID 50S NEAR THE PA BORDER. ANY CHANCE OF
MEASURABLE PRECIP WILL END FRIDAY EVENING AS THE DEPARTING LOW
DRAGS THE FRONT SOUTH AND HIGH PRESSURE BUILDS. THERE WILL STILL
BE LOW LEVEL OVERRUNNING...SO COULD SEE SOME LINGERING DRIZZLE.

THE FIRST HALF OF SATURDAY SHOULD BE DRY AS SHORTWAVE RIDGING
MOVES OVERHEAD. HOWEVER...THE TREND HAS BEEN FASTER WITH
ISENTROPIC LIFT AHEAD OF THE NEXT LOW OVER THE PLAINS...WITH RAIN
POSSIBLE ACROSS WESTERN AREAS BY AFTERNOON AND ACROSS MOST OF THE
AREA OVERNIGHT. HIGHS MAY GET A BOOST FROM MIDDAY SUN
BREAKS...POTENTIALLY REACHING THE 60S IN MOST AREAS.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE THROUGH MONDAY IS IN REASONABLE...IF ROUGH...AGREEMENT.
THE STATIONARY BOUNDARY TO OUR SOUTH WILL START TO LIFT NORTH AS
ANOTHER WAVE OF LOW PRESSURE TRACKS EASTWARD FROM THE CENTRAL
PLAINS AND OHIO VALLEY. THE WEDGE OF COOLER AIR WILL BE HARD TO
DISLODGE AND WHILE SOME MILDER AIR MAY TRY TO ENTER THE CWA LATE
SUNDAY OR MONDAY...MOST OF THE REGION WILL PROBABLY STAY ON THE
COOL SIDE OF THE BOUNDARY. AFTER THE TROUGH AXIS ALOFT PASSES
THROUGH LATE MONDAY...GUIDANCE DIFFERS IN THE POTENTIAL FOR
ANOTHER WAVE TO MOVE NORTHEASTWARD UP THE COAST...SO WE MAINTAIN A
CHANCE OF SHOWERS. OTHER THAN THE BRIEF CHANCE OF A WARM
INTERLUDE WITH THE PASSING WAVE LATE SUNDAY INTO
MONDAY...TEMPERATURES WILL BE ON THE COOL SIDE OF NORMAL.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
OVERALL THEME OF FORECAST DOES NOT CHANGE APPRECIABLY THROUGH
FRIDAY NIGHT AS THE REGION WILL REMAIN ENTRENCHED IN MARITIME
FLOW/CAD WEDGE. MAIN ISSUE WILL BE TIMING IN IFR RESTRICTION (MORE
LIKELY OVERNIGHT THAN DURING DAY). FOG...SHOWERS...AND DRIZZLE
COULD REDUCE VSBY AT TIMES...BUT CLOUDS WILL BE THE BIGGER ISSUE.
BEST CHANCE AT POTENTIALLY MODERATE RAIN WILL CROSS THE AREA
DURING THE MID MORNING HOURS (QUICKER THAN PREVIOUS FORECASTS).
ANY AFTERNOON THUNDERSTORMS SHOULD STAY SOUTH OF CHO. COULD SEE A
RISE TO SOLID VFR CONDITIONS ON SATURDAY...BUT ADDITIONAL RAIN AND
LOW CLOUDS WILL ARRIVE SATURDAY NIGHT AND CONTINUE THROUGH MONDAY
IF NOT LONGER.

&&

.MARINE...
ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING
5- 10 KT WITH OCCASIONAL INCREASES TO 15 KT. SOME GUIDANCE
INDICATES PERIODIC FLIRTING WITH SCA-LEVEL GUSTS THIS
AFTERNOON...BUT LACK OF CONSISTENT SIGNAL PRECLUDES A HEADLINE FOR
NOW. SAME GOES FOR FRIDAY AFTERNOON. WINDS MAY TURN MORE TO THE SE
SATURDAY NIGHT BUT REMAIN SUB-SCA. BETTER CHANCE OF SCA CONDITIONS
SUNDAY AND MONDAY WITH A MORE POTENT LOW PRESSURE SYSTEM MOVING
THROUGH.

&&

.TIDES/COASTAL FLOODING...
EASTERLY FLOW HAS HELPED WATER LEVELS CONTINUE TO RISE AND HAVE
ISSUED COASTAL FLOOD ADVISORIES FOR MOST OF OUR CHESAPEAKE BAY
SHORE FOR THIS MORNING`S CYCLE. STILL UNCERTAIN ABOUT TIDAL
POTOMAC AND THE FAR NORTH END OF THE BAY WHERE THE EASTERLY FLOW
MAY BE KEEPING WATER LEVELS JUST BELOW MINOR THRESHOLDS...BUT WILL
NEED TO FOLLOW THIS CLOSELY. WITH OUR AREA EXPECTED TO REMAIN ON
THE NORTH SIDE OF THE FRONT WITH PERSISTENT EASTERLY FLOW...MINOR
FLOODING WILL REMAIN A CONCERN FOR THE NEXT SEVERAL DAYS.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY UNTIL NOON EDT TODAY FOR MDZ018.
     COASTAL FLOOD ADVISORY FROM 8 AM THIS MORNING TO 3 PM EDT THIS
     AFTERNOON FOR MDZ011.
     COASTAL FLOOD ADVISORY UNTIL 3 PM EDT THIS AFTERNOON FOR
     MDZ014.
     COASTAL FLOOD ADVISORY UNTIL 10 AM EDT THIS MORNING FOR MDZ017.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...RCM
AVIATION...ADS/RCM
MARINE...ADS/RCM
TIDES/COASTAL FLOODING...RCM





000
FXUS61 KLWX 280759
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
359 AM EDT THU APR 28 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED TO THE SOUTH THROUGH FRIDAY.
WAVES OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY DURING THIS
TIME. THE BOUNDARY WILL DROP FARTHER SOUTH SATURDAY...BUT IT WILL
THEN LIFT NORTHWARD CLOSER TO THE REGION AGAIN SUNDAY AND MONDAY
AS ANOTHER WAVE OF LOW PRESSURE MOVES ALONG IT.

&&

.NEAR TERM /THROUGH TONIGHT/...
STALLED SFC BOUNDARY STILL LOCATED NEAR NC THIS MORNING...SNAKING
TO VERTICALLY STACKED LOW PRESSURE OVER IOWA. MARITIME FLOW
DOMINATES WITH PLENTY OF CLOUD COVER BUT VERY LITTLE PRECIP AT
THIS HOUR. THIS WILL CHANGE QUICKLY THIS MORNING AS ARC OF
CONVECTION CURRENTLY OVER THE OHIO VALLEY PUSHES EASTWARD. THIS
WARRANTED A MUCH FASTER RAMP UP IN POPS AS MOST GUIDANCE SHOWS
THIS ACTIVITY CONTINUING TO PUSH EAST ACROSS THE AREA. RECENT
LIGHTNING TRENDS SUGGEST THUNDER WILL BE ABSENT BY THE TIME IT
REACHES OUR CWA.

BEHIND THIS ACTIVITY...FAIRLY SUBSTANTIAL DRY SLOT IS NOTED IN
WATER VAPOR IMAGERY. THIS WILL LIKELY LEAD TO RAPIDLY DIMINISHING
COVERAGE OF SHOWERS DURING THE AFTERNOON. HOWEVER...WITH
ADDITIONAL WEAK SHORTWAVE ENERGY AND CONTINUED OVERRUNING...SOME
LIGHT SHOWERS OR SPRINKLES WILL REMAIN POSSIBLE. IN ADDITION...BL
HEATING WILL TAKE PLACE S/W OF THE CWA IN AN ENVIRONMENT OF
MODERATE DEEP LAYER SHEAR. SOME OF THIS THUNDERSTORM ACTIVITY MAY
PUSH INTO THE POTOMAC HIGHLANDS AND ALONG THE SOUTHERN CWA BORDER
THIS AFTERNOON. THE BULK OF THE CWA WILL BE ENTRENCHED IN THE
STABLE CAD WEDGE. HOWEVER...NOT OUT OF THE QUESTION A STRONGER
CELL ALONG THE SW BORDER COULD CONTAIN HAIL. HIGHS TODAY WILL
STRUGGLE TO THE MID 50S IN THE NORTH AND PERHAPS REACH THE MID 60S
SOUTH.

THE OPENED LOW WILL BE NEAR PA TONIGHT. THUS THE HIGHEST POPS
WILL BE IN THE NORTHERN CWA. LOW LEVELS WILL BE SATURATED ACROSS
THE ENTIRE AREA THOUGH...SO HAVE INTRODUCED PATCHY DRIZZLE AND FOG
TO THE FORECAST. LOWS WILL RANGE FROM THE MID 40S TO MID 50S.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
WEAK SFC LOW WILL STILL BE NEAR THE AREA ON FRIDAY WITH CAD WEDGE
FRONT NEARLY UNCHANGED. HOWEVER...TREND IN 00Z GUIDANCE IS TO KEEP
SHORTWAVE TROUGH FARTHER TO THE NORTH. SO SEE LITTLE REASON TO
CHANGE POPS...CAPPING IN THE CHANCE CATEGORY WITH HIGHEST NEAR PA
BORDER. THE LOW MAY DRAW SOME WARMER AIR INTO CENTRAL VA...BUT
HIGHS WILL REMAIN IN THE MID 50S NEAR THE PA BORDER. ANY CHANCE OF
MEASURABLE PRECIP WILL END FRIDAY EVENING AS THE DEPARTING LOW
DRAGS THE FRONT SOUTH AND HIGH PRESSURE BUILDS. THERE WILL STILL
BE LOW LEVEL OVERRUNNING...SO COULD SEE SOME LINGERING DRIZZLE.

THE FIRST HALF OF SATURDAY SHOULD BE DRY AS SHORTWAVE RIDGING
MOVES OVERHEAD. HOWEVER...THE TREND HAS BEEN FASTER WITH
ISENTROPIC LIFT AHEAD OF THE NEXT LOW OVER THE PLAINS...WITH RAIN
POSSIBLE ACROSS WESTERN AREAS BY AFTERNOON AND ACROSS MOST OF THE
AREA OVERNIGHT. HIGHS MAY GET A BOOST FROM MIDDAY SUN
BREAKS...POTENTIALLY REACHING THE 60S IN MOST AREAS.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE THROUGH MONDAY IS IN REASONABLE...IF ROUGH...AGREEMENT.
THE STATIONARY BOUNDARY TO OUR SOUTH WILL START TO LIFT NORTH AS
ANOTHER WAVE OF LOW PRESSURE TRACKS EASTWARD FROM THE CENTRAL
PLAINS AND OHIO VALLEY. THE WEDGE OF COOLER AIR WILL BE HARD TO
DISLODGE AND WHILE SOME MILDER AIR MAY TRY TO ENTER THE CWA LATE
SUNDAY OR MONDAY...MOST OF THE REGION WILL PROBABLY STAY ON THE
COOL SIDE OF THE BOUNDARY. AFTER THE TROUGH AXIS ALOFT PASSES
THROUGH LATE MONDAY...GUIDANCE DIFFERS IN THE POTENTIAL FOR
ANOTHER WAVE TO MOVE NORTHEASTWARD UP THE COAST...SO WE MAINTAIN A
CHANCE OF SHOWERS. OTHER THAN THE BRIEF CHANCE OF A WARM
INTERLUDE WITH THE PASSING WAVE LATE SUNDAY INTO
MONDAY...TEMPERATURES WILL BE ON THE COOL SIDE OF NORMAL.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
OVERALL THEME OF FORECAST DOES NOT CHANGE APPRECIABLY THROUGH
FRIDAY NIGHT AS THE REGION WILL REMAIN ENTRENCHED IN MARITIME
FLOW/CAD WEDGE. MAIN ISSUE WILL BE TIMING IN IFR RESTRICTION (MORE
LIKELY OVERNIGHT THAN DURING DAY). FOG...SHOWERS...AND DRIZZLE
COULD REDUCE VSBY AT TIMES...BUT CLOUDS WILL BE THE BIGGER ISSUE.
BEST CHANCE AT POTENTIALLY MODERATE RAIN WILL CROSS THE AREA
DURING THE MID MORNING HOURS (QUICKER THAN PREVIOUS FORECASTS).
ANY AFTERNOON THUNDERSTORMS SHOULD STAY SOUTH OF CHO. COULD SEE A
RISE TO SOLID VFR CONDITIONS ON SATURDAY...BUT ADDITIONAL RAIN AND
LOW CLOUDS WILL ARRIVE SATURDAY NIGHT AND CONTINUE THROUGH MONDAY
IF NOT LONGER.

&&

.MARINE...
ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING
5- 10 KT WITH OCCASIONAL INCREASES TO 15 KT. SOME GUIDANCE
INDICATES PERIODIC FLIRTING WITH SCA-LEVEL GUSTS THIS
AFTERNOON...BUT LACK OF CONSISTENT SIGNAL PRECLUDES A HEADLINE FOR
NOW. SAME GOES FOR FRIDAY AFTERNOON. WINDS MAY TURN MORE TO THE SE
SATURDAY NIGHT BUT REMAIN SUB-SCA. BETTER CHANCE OF SCA CONDITIONS
SUNDAY AND MONDAY WITH A MORE POTENT LOW PRESSURE SYSTEM MOVING
THROUGH.

&&

.TIDES/COASTAL FLOODING...
EASTERLY FLOW HAS HELPED WATER LEVELS CONTINUE TO RISE AND HAVE
ISSUED COASTAL FLOOD ADVISORIES FOR MOST OF OUR CHESAPEAKE BAY
SHORE FOR THIS MORNING`S CYCLE. STILL UNCERTAIN ABOUT TIDAL
POTOMAC AND THE FAR NORTH END OF THE BAY WHERE THE EASTERLY FLOW
MAY BE KEEPING WATER LEVELS JUST BELOW MINOR THRESHOLDS...BUT WILL
NEED TO FOLLOW THIS CLOSELY. WITH OUR AREA EXPECTED TO REMAIN ON
THE NORTH SIDE OF THE FRONT WITH PERSISTENT EASTERLY FLOW...MINOR
FLOODING WILL REMAIN A CONCERN FOR THE NEXT SEVERAL DAYS.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY UNTIL NOON EDT TODAY FOR MDZ018.
     COASTAL FLOOD ADVISORY FROM 8 AM THIS MORNING TO 3 PM EDT THIS
     AFTERNOON FOR MDZ011.
     COASTAL FLOOD ADVISORY UNTIL 3 PM EDT THIS AFTERNOON FOR
     MDZ014.
     COASTAL FLOOD ADVISORY UNTIL 10 AM EDT THIS MORNING FOR MDZ017.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RCM
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...RCM
AVIATION...ADS/RCM
MARINE...ADS/RCM
TIDES/COASTAL FLOODING...RCM





000
FXUS61 KLWX 280126 AAA
AFDLWX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
926 PM EDT WED APR 27 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED NEAR THE VIRGINIA-NORTH CAROLINA
BORDER THROUGH FRIDAY. WAVES OF LOW PRESSURE WILL RIDE ALONG THE
BOUNDARY DURING THIS TIME. THE BOUNDARY WILL DROP FARTHER SOUTH
SATURDAY...BUT ANOTHER WAVE OF LOW PRESSURE WILL TRACK ALONG THE
FRONT SUNDAY NIGHT.

&&

.NEAR TERM /THROUGH THURSDAY/...

LIGHT SHOWERS CONTINUE ACROSS CNTRL VA ALONG 850 MB FRONT. THESE
ARE EXPECTED TO CONTINUE THROUGH THE EVENING WHILE NRN AREAS
REMAIN DRY. OVERNIGHT...850 MB FRONT IS EXPECTED TO START LIFTING
NORTH AS WEAK HEIGHT FALLS AND SFC/850MB WAVE ALONG THE IL/IN
BORDER SPREAD/MOVE EAST. RAIN APPEARS LIKELY EAST AND DEFINITE
WEST AS H85 FRONT TRIES TO LIFT NORTH ACROSS THE REST OF THE FCST
AREA. RAINFALL TOTALS APPEAR IN THE 0.25 TO 0.5 INCH RANGE EXCEPT
HIGHER IN UPSLOPE AREAS. MID-LEVEL DRY SLOT MOVES IN THU NIGHT
WITH MAINLY LOW CLOUDS...DRIZZLE AND FOG.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
PTTN REMAINS UNCHGD THRU THE END OF THE WEEK...AS STALLED FRONT
POISED S OF CWFA. ANY S/WV RIDING ALONG THIS BNDRY CUD TRIGGER A
FEW SHRA. THERE WONT BE MANY SUBSTANTIVE CHGS TO THE FCST GIVEN
THESE SUBTLETIES...AND THE CHALLENGES W/ FORECASTING THEM THIS
FAR OUT.

ONE KEY FEATURE THAT IS DISCERNABLE ATTM IS THE CLOSED LOW ACRS
THE PLAINS OPENS UP AND TRAVERSES THE CONUS DURING THE PD. THE SFC
REFLECTION WL MIGRATE EWD AS WELL...ALONG THE BNDRY... WHICH WL
PROVIDE THE IMPETUS FOR SHRA. THEREFORE WL INCR POPS TO LKLYS THU
MIDDAY THRU MIDNGT.

BYD THAT IT IS UNCLR HOW MUCH MSTR THE SUBSEQUENT VORT WL HV...
EXACTLY WHERE IT WL TRACK...AND HOW STRONG IT WL BE. WL REVERT
BACK TO CHC POPS FOR FRI.

FEW TEMP CHGS DURING THE PD AS WELL. IT WL BE TOUGH FOR MUCH OF MD
TO CRACK 60 DEGF...SPCLY ON THU.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL REMAIN WEDGED ALONG THE EASTERN SLOPES OF THE
APPALACHIAN MOUNTAINS SATURDAY THROUGH SUNDAY. SOME OVERRUNNING
WARMTH AND MOISTURE SATURDAY NIGHT AND AN APPROACHING UPPER LEVEL
DISTURBANCE WILL RIDE ALONG THE OHIO VALLEY INTO OUR REGION AND
BRING A THREAT FOR PERIODS OF RAIN.

PERIODS OF RAIN WILL BECOME MORE PRONOUNCED AND PROLONGED SUNDAY
INTO SUNDAY NIGHT AS THE MAIN UPPER LEVEL TROUGH PIVOTS INTO THE
AREA AND A SURFACE LOW PRESSURE SYSTEM DEVELOPS OVER SOUTHWEST
VIRGINIA.

ADDITIONAL UPPER LEVEL ENERGY WILL ROTATE WITHIN THE MAIN TROUGH OF
LOW PRESSURE MONDAY INTO MONDAY NIGHT...LEAVING THE CHANCE FOR
ADDITIONAL RAIN SHOWERS ACROSS THE REGION.

THE SURFACE LOW AND UPPER ENERGY SHOULD EXIT THE EAST COAST TUESDAY
TO ALLOW FOR A RIDGE OF HIGH PRESSURE TO BUILD INTO THE REGION
TUESDAY NIGHT AND WEDNESDAY. DRIER CONDITIONS ON THE WAY.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
UNSTTLD PTTN THRU THE TAF PD...AND THRU THE END OF THE WK FOR
THAT MATTER. STALLED FRNTL BNDRY S OF THE TERMINALS. ONSHORE FLOW
BRINGING MARINE STRATUS/STCU. WL STICK MAINLY W/ MVFR FLGT CONDS.
CUD BE A FEW SHRA INVOF CHO THIS EVNG...BUT LOW CONFIDENCE. BETTER
CHC AT SEEING SHRA THU PM. PDS OF IFR PSBL TNGT...AND SPCLY THU
AFTN-NGT. HV NOT PLACED AOB IFR IN ANY TAF ATTM.

SHOULD IMPROVE TO VFR ON FRI. VFR CONDITIONS EXPECTED SATURDAY AS
WELL. WINDS NORTHEAST LESS THAN 5 KNOTS. VFR CONDITIONS BECOMING
MVFR OR IFR SATURDAY NIGHT WITH APPROACHING RAIN SHOWERS FROM THE
WEST. WINDS BECOMING SOUTHEAST AROUND 5 KNOTS.

&&

.MARINE...
ONSHORE FLOW WL REMAIN IN PLACE THRU THE END OF THE WEEK INTO THE
WKND. WIND SPDS AOB 10-15 KT THRU THE PD.

&&

.TIDES/COASTAL FLOODING...WATER LEVELS REMAIN ELEVATED ACROSS THE
BAY AND POTOMAC. ONSHORE FLOW IS LIKELY TO RAISE WATER LEVELS
FURTHER WITH MINOR COASTAL FLOODING LIKELY AT ANNAPOLIS...SOLOMONS
AND STRAITS POINT THU MORNING. WILL LEFT NEXT SHIFT EVALUATE.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...LFR
SHORT TERM...HTS
LONG TERM...KLW
AVIATION...HTS/KLW
MARINE...HTS/KLW
TIDES/COASTAL FLOODING...LFR





000
FXUS61 KLWX 271848
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
248 PM EDT WED APR 27 2016

.SYNOPSIS...
A COLD FRONT WILL REMAIN STALLED NEAR THE VIRGINIA-NORTH CAROLINA
BORDER THROUGH FRIDAY. WAVES OF LOW PRESSURE WILL RIDE ALONG THE
BOUNDARY DURING THIS TIME. THE BOUNDARY MAY DROP A BIT FARTHER
SOUTH SATURDAY...BUT ANOTHER WAVE OF LOW PRESSURE WILL TRACK ALONG
THE FRONT FOR SUNDAY INTO MONDAY.
&&

.NEAR TERM /THROUGH TONIGHT/...
THE BNDRY REMAINS STALLED ACRS SRN VA TAFTN. TEMPS ONCE AGN IN
THE LWR 80S SOUTH OF THIS BNDRY...BUT ONLY IN THE LWR 50S ACRS
MUCH OF MD. A RDG OF SFC HIPRES EXTENDS DOWN THE COAST FM NEW
ENGLAND. IN ADDITION...A RDG AXIS EXISTS ALOFT ACRS THE GRTLKS TO
SERN CONUS. THEREFORE...THE NEAREST DIURNAL TSRA DVLPG ACRS ERN
KY/SRN WVA/WRN VA. THE QSTN WL BE WHETHER THESE STORMS CAN REACH
SRN CWFA. BASED ON SYNOP SETUP AND STBL AMS...AM BETTING AGAINST
IT. TO PROVIDE A BUFFER NEED TO INCL CHC POPS ACRS CENTRAL VA/SRN
MD...BUT FCST UNDERCUTS MOS SIGNIFICANTLY.

ISENT UPGLIDE IMPRV OVNGT...SO WL INCR POPS SLGTLY. AM NOT SOLD ON
ACCUM QPF...SO AM KEEPING POPS AT CHC.

UTILIZED A MDL BLEND FOR MIN-T...WHICH YIELDS UPR 40S ACRS NRN MD
TO MID 50S CENTRAL VA.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
PTTN REMAINS UNCHGD THRU THE END OF THE WEEK...AS STALLED FRONT
POISED S OF CWFA. ANY S/WV RIDING ALONG THIS BNDRY CUD TRIGGER A
FEW SHRA. THERE WONT BE MANY SUBSTANTIVE CHGS TO THE FCST GIVEN
THESE SUBTLETIES...AND THE CHALLENGES W/ FORECASTING THEM THIS
FAR OUT.

ONE KEY FEATURE THAT IS DISCERNABLE ATTM IS THE CLOSED LOW ACRS
THE PLAINS OPENS UP AND TRAVERSES THE CONUS DURING THE PD. THE SFC
REFLECTION WL MIGRATE EWD AS WELL...ALONG THE BNDRY... WHICH WL
PROVIDE THE IMPETUS FOR SHRA. THEREFORE WL INCR POPS TO LKLYS THU
MIDDAY THRU MIDNGT.

BYD THAT IT IS UNCLR HOW MUCH MSTR THE SUBSEQUENT VORT WL HV...
EXACTLY WHERE IT WL TRACK...AND HOW STRONG IT WL BE. WL REVERT
BACK TO CHC POPS FOR FRI.

FEW TEMP CHGS DURING THE PD AS WELL. IT WL BE TOUGH FOR MUCH OF MD
TO CRACK 60 DEGF...SPCLY ON THU.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL REMAIN WEDGED ALONG THE EASTERN SLOPES OF THE
APPALACHIAN MOUNTAINS SATURDAY THROUGH SUNDAY. SOME OVERRUNNING
WARMTH AND MOISTURE SATURDAY NIGHT AND AN APPROACHING UPPER LEVEL
DISTURBANCE WILL RIDE ALONG THE OHIO VALLEY INTO OUR REGION AND
BRING A THREAT FOR PERIODS OF RAIN.

PERIODS OF RAIN WILL BECOME MORE PRONOUNCED AND PROLONGED SUNDAY
INTO SUNDAY NIGHT AS THE MAIN UPPER LEVEL TROUGH PIVOTS INTO THE
AREA AND A SURFACE LOW PRESSURE SYSTEM DEVELOPS OVER SOUTHWEST
VIRGINIA.

ADDITIONAL UPPER LEVEL ENERGY WILL ROTATE WITHIN THE MAIN TROUGH OF
LOW PRESSURE MONDAY INTO MONDAY NIGHT...LEAVING THE CHANCE FOR
ADDITIONAL RAIN SHOWERS ACROSS THE REGION.

THE SURFACE LOW AND UPPER ENERGY SHOULD EXIT THE EAST COAST TUESDAY
TO ALLOW FOR A RIDGE OF HIGH PRESSURE TO BUILD INTO THE REGION
TUESDAY NIGHT AND WEDNESDAY. DRIER CONDITIONS ON THE WAY.
&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
UNSTTLD PTTN THRU THE TAF PD...AND THRU THE END OF THE WK FOR
THAT MATTER. STALLED FRNTL BNDRY S OF THE TERMINALS. ONSHORE FLOW
BRINGING MARINE STRATUS/STCU. WL STICK MAINLY W/ MVFR FLGT CONDS.
CUD BE A FEW SHRA INVOF CHO THIS EVNG...BUT LOW CONFIDENCE. BETTER
CHC AT SEEING SHRA THU PM. PDS OF IFR PSBL TNGT...AND SPCLY THU
AFTN-NGT. HV NOT PLACED AOB IFR IN ANY TAF ATTM.

SHOULD IMPROVE TO VFR ON FRI. VFR CONDITIONS EXPECTED SATURDAY AS
WELL. WINDS NORTHEAST LESS THAN 5 KNOTS. VFR CONDITIONS BECOMING
MVFR OR IFR SATURDAY NIGHT WITH APPROACHING RAIN SHOWERS FROM THE
WEST. WINDS BECOMING SOUTHEAST AROUND 5 KNOTS.
&&

.MARINE...
ONSHORE FLOW WL REMAIN IN PLACE THRU THE END OF THE WEEK INTO THE
WKND. WIND SPDS AOB 10-15 KT THRU THE PD.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HTS
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...KLW
AVIATION...HTS/KLW
MARINE...HTS





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