366
FXUS61 KLWX 150031
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
831 PM EDT THU AUG 14 2025
SYNOPSIS
A COLD FRONT WILL APPROACH AND MOVE THROUGH THE FORECAST AREA TODAY
BEFORE STALLING TO THE SOUTH ON FRIDAY. SURFACE HIGH PRESSURE
BRIEFLY BUILDS OVERHEAD SATURDAY AND SUNDAY AHEAD OF ANOTHER COLD
FRONT SET TO MOVE THROUGH THE REGION EARLY NEXT WEEK.
NEAR TERM /THROUGH FRIDAY/
A WEAKENING COLD FRONT WILL CONTINUE TO SAG SOUTH AND EAST OF
THE AREA THIS EVENING. THIS WILL LEAD TO DECREASING SHOWER AND
THUNDERSTORM ACTIVITY AS WELL AS A SLIGHT DECREASE IN HUMIDITY
OVERNIGHT. THE FRONT LOOKS TO STALL AND EVENTUALLY DISSIPATE IN
THE VICINITY OF THE DELMARVA FRIDAY AS SUBTROPICAL RIDGING
BUILDS FROM THE SOUTH.
LOWS TONIGHT WILL FALL BACK INTO THE MID TO UPPER 60S AND LOW 70S
WITH EVEN A FEW UPPER 50S AND LOW 60S ACROSS THE ALLEGHENY
MOUNTAINS. DEWPOINTS WILL FALL BACK INTO THE 60S AS WELL WHICH IS A
SLIGHT DECREASE IN HUMIDITY OVER THE PAST FEW DAYS. LOW CLOUDS ARE
POSSIBLE OVERNIGHT ALONG WITH PATCHY FOG ESPECIALLY IN AREAS THAT
DID SEE THE RAIN (MAINLY EAST OF THE BLUE RIDGE).
THE AFOREMENTIONED COLD FRONT WILL BE LOCATED JUST SOUTH OF THE
FORECAST AREA COME FRIDAY MORNING AND IS FORECAST TO SLOWLY DRIFT
SOUTH TOWARDS THE CAROLINAS THROUGHOUT THE DAY. THE NEARBY FRONT
WILL YIELD AFTERNOON SHOWER AND THUNDERSTORM CHANCES, MAINLY IN THE
SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA. TO THE NORTH,
SURFACE HIGH PRESSURE CENTERED OVER QUEBEC WILL EXTEND SOUTH OVER
THE NORTHERN MID-ATLANTIC. THIS DRY CANADIAN AIRMASS WILL LIMIT
PRECIPITATION CHANCES TO 35% OR LESS AND ADDITIONALLY PROVIDE
SLIGHTLY COOLER TEMPERATURES. HIGH TEMPERATURES FRIDAY WILL BE
IN THE 80S FOR MOST WITH HIGHER ELEVATIONS STAYING IN THE 70S.
SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/
THE WEEKEND WILL FEATURE TYPICAL SUMMERTIME CONDITIONS WITH
DECREASED RAIN CHANCES AS SURFACE HIGH PRESSURE/SUBTROPICAL RIDGING
BUILD ACROSS THE REGION. AN ISOLATED SHOWER OR T-STORM CANNOT BE
RULED OUT OVER THE TERRAIN OR ALONG THE WESTERN SHORE OF THE BAY DUE
IN PART TO THE INITIATION OF BAY/RIVER BREEZE. MEANWHILE, WHAT
IS LEFT OF THE DISSIPATING FRONT SITS DOWN ALONG THE COASTAL
CAROLINAS WITH AN AREA OF LOW PRESSURE SET TO FESTER RIGHT ALONG
THE COAST. THIS AREA OF LOW PRESSURE WILL HELP CONTRIBUTE MORE
HUMIDITY ACROSS THE REGION SATURDAY AND ESPECIALLY DURING THE
DAY SUNDAY. AT THE SAME TIME, AN INCOMING COLD FRONT FROM THE
CENTRAL GREAT LAKES AND NORTHERN OHIO RIVER VALLEY WILL APPROACH
THE REGION SUNDAY BEFORE CROSSING/DISSIPATING LATE SUNDAY NIGHT
INTO MONDAY. WITH LOW PRESSURE OFF THE CAROLINA COAST AND AN
ENCROACHING FRONT EXPECT AN UPTICK OF SHOWER/THUNDERSTORM
ACTIVITY MAINLY WEST OF THE BLUE RIDGE LATE SUNDAY AFTERNOON.
THERE SHOULD BE JUST ENOUGH RESIDUAL DRY AIR IN PLACE TO KEEP
MOST DRY THROUGH EARLY NEXT WEEK.
HIGH TEMPERATURES SATURDAY WILL CLIMB BACK INTO THE MID TO
UPPER 80S FOR MOST WITH UPPER 70S AND LOW 80S OVER THE
MOUNTAINS. HEAT INDICES VALUES SATURDAY SHOULD REMAIN IN THE
UPPER 80S AND LOW 90S WITH DEWPOINTS HANGING IN THE UPPER 60S
AND LOW 70S. BY SUNDAY, THE HIGH HEAT RETURNS WITH HIGHS IN THE
LOW TO MID 90S AND HEAT INDICES ESPECIALLY EAST OF THE
ALLEGHENIES PUSH TOWARD 100 DEGREES. OVERNIGHT LOWS WILL REMAIN
IN THE UPPER 60S AND LOW 70S. PATCHY FOG AND LOW CLOUDS WILL
REMAIN POSSIBLE EACH NIGHT WITH LIGHT WINDS EXPECTED.
LONG TERM /MONDAY THROUGH THURSDAY/
THE HIGH SHOULD PUSH FAR ENOUGH TO THE EAST BY SUNDAY NIGHT THAT
THE AIRMASS TRAJECTORIES SHOULD BE MORE CONTINENTAL VERSUS
MARINE. PRIMARY FORCING WITH A TROUGH AND ASSOCIATED FRONT
SHOULD REMAIN FAR ENOUGH TO THE NORTH TO KEEP PRECIPITATION
CHANCES TO A MINIMUM. HOWEVER, SOME REMNANT SHOWERS COULD MOVE
INTO THE AREA SUNDAY NIGHT. THIS FRONT WILL SLIP SOUTHWARD INTO
THE AREA MONDAY. HOWEVER, IT MAY MAKE ENOUGH PROGRESS THAT THE
HIGHEST THUNDERSTORM CHANCES WILL RESIDE ACROSS SOUTHERN PARTS
OF THE FORECAST AREA.
TOWARD THE MIDDLE OF THE WEEK, THE FRONT MAY STALL OUT OR WAVER
ACROSS THE MID ATLANTIC. SURFACE HIGH PRESSURE WILL BUILD
SOUTHEASTWARD FROM CANADA ACROSS NEW ENGLAND. THE HIGH LATITUDE WAVE
TRAIN WILL CAUSE THE UPPER LEVEL RIDGE AXIS TO RETROGRADE FROM THE
CENTRAL US TO THE ROCKIES, RESULTING IN NORTHWESTERLY FLOW ALONG THE
EAST COAST. THE CURRENT FORECAST FAVORS A CLOUDIER AND COOLER
SOLUTION, WITH ONSHORE FLOW LEADING TO MORE STABLE CONDITIONS EAST
OF THE MOUNTAINS. HOWEVER, WITH THE STALLED FRONT NEARBY ALONG WITH
TERRAIN FORCING, SHOWERS AND THUNDERSTORMS WILL BE IN THE FORECAST
EACH DAY.
AVIATION /01Z FRIDAY THROUGH TUESDAY/
PREDOMINANT VFR CONDITIONS ARE EXPECTED OVERNIGHT INTO FRIDAY
MORNING AT MOST OF THE TERMINALS. SOME MVFR TO PERHAPS PATCHY
POCKETS OF IFR ARE POSSIBLE LATE TONIGHT INTO FRIDAY MORNING MAINLY
AT TERMINALS EAST OF THE BLUE RIDGE DUE TO LOW CLOUDS. LOW CLOUDS
HAVE BEEN INCLUDED ACROSS THE CORRIDOR WITH FEW-SCT CIGS BOUNCING
BETWEEN 025-050 KFT DURING THE EARLY FRIDAY MORNING PERIOD. GIVEN
THE LINGERING MOISTURE AND LIGHT WINDS SIMILAR TO THE PAST FEW
NIGHTS ALONG WITH CAM GUIDANCE, WENT AHEAD WITH THE ADDITION IN
THIS TAF CYCLE. SOME PATCHY FOG IS ALSO POSSIBLE WITH THE
HIGHEST CONFIDENCE AT KCHO GETTING DOWN BELOW 3SM. ELSEWHERE FOG
IS POSSIBLE, BUT MAY BE RELEGATED TO MIFG AT KIAD, KDCA, AND
KBWI WITH RECENT RAINFALL. WINDS WILL REMAIN LIGHT AND VARIABLE
TONIGHT BEFORE BECOMING MORE NORTHERLY FRIDAY AT LESS THAN 10
KTS.
VFR CONDITIONS SHOULD PREVAIL ONCE AGAIN FRIDAY INTO FRIDAY NIGHT AS
THE COLD FRONT SAGS FURTHER SOUTH AND EAST OF THE REGION. A FEW
SPOTTY SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT ACROSS THE
CORRIDOR AND DOWN TOWARD KRIC. OVERALL COVERAGE WILL BE MORE
SPOTTY AND LESS THAN THURSDAY (AUGUST 13, 2025). DID ADD BRIEF
PROB30S FOR TSRA ACROSS THE CORRIDOR GIVEN THE SIGNALS FROM
RECENT CAM GUIDANCE.
PREVAILING VFR CONDITIONS ARE EXPECTED ON SATURDAY AS WINDS REMAIN
LIGHT OUT OF THE EAST. KCHO AND KMRB HAVE THE GREATEST CHANCE OF
SEEING AN ISOLATED AFTERNOON SHOWER OR THUNDERSTORM, ALTHOUGH
PRECIPITATION FARTHER EAST CANNOT BE RULED OUT.
AN ISOLATED THUNDERSTORM IS POSSIBLE LATE SUNDAY INTO MONDAY AS A
WEAK FRONT MOVES THROUGH THE AREA. EASTERLY FLOW MAY LEAD TO SUB-VFR
CEILINGS MONDAY NIGHT INTO TUESDAY.
MARINE
WINDS REMAIN WELL BELOW SMALL CRAFT ADVISORY CRITERIA THROUGH THE
WEEKEND, GUSTING 10 KNOTS OR LESS. LIGHT AND VARIABLE WINDS
EXPECTED TONIGHT. WINDS SHIFT TO EASTERLY FRIDAY, BLOWING 5 TO
10 KNOTS IN THE AFTERNOON. ON SATURDAY, WINDS REMAIN LIGHT OUT
OF THE EAST. ISOLATED THUNDERSTORMS ARE POSSIBLE OVER THE WATERS
FRIDAY WITH SMWS POSSIBLE, ALTHOUGH NOT LIKELY. NO MARINE
HAZARDS ARE EXPECTED ON SATURDAY AS PRECIPITATION IS EXPECTED TO
REMAIN WEST OF THE WATERS.
SOUTHERLY WINDS ON SUNDAY WILL BECOME NORTHERLY SUNDAY NIGHT OR
MONDAY AS A FRONT MOVES THROUGH THE AREA. THUNDERSTORM CHANCES LOOK
TO REMAIN FAIRLY ISOLATED. EASTERLY WINDS MAY INCREASE TUESDAY, BUT
IT REMAINS UNCERTAIN IF ADVISORIES WILL BE NEEDED.
TIDES/COASTAL FLOODING
ELEVATED TIDAL ANOMALIES LOOK TO CONTINUE THROUGH THE END OF THE
WEEK GIVEN THE RECENT FULL MOON AND LIGHT WINDS. WHILE MINOR
TIDAL FLOODING IS NOT EXPECTED, SOME CYCLES COULD GO INTO ACTION
STAGE DURING THE HIGH ASTRONOMICAL TIDES (ESPECIALLY AT
ANNAPOLIS AND PERHAPS DAHLGREN/ALEXANDRIA).
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
SYNOPSIS...EST
NEAR TERM...EST/AVS
SHORT TERM...EST
LONG TERM...ADS
AVIATION...ADS/AVS/EST
MARINE...ADS/AVS/EST
TIDES/COASTAL FLOODING...LWX
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