511
FXUS61 KLWX 100745
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
345 AM EDT WED SEP 10 2025
SYNOPSIS
CANADIAN HIGH PRESSURE REMAINS SITUATED TO OUR NORTH TODAY AS A
WAVE OF LOW PRESSURE PASSES OFFSHORE TO THE SOUTHEAST. A DRY
FRONT WILL DISSIPATE AS IT APPROACHES ON THURSDAY, THEN ANOTHER
AREA OF CANADIAN HIGH PRESSURE WILL DRIFT TOWARD NEW ENGLAND THIS
WEEKEND, RESULTING IN CONTINUED DRY CONDITIONS.
NEAR TERM /THROUGH TONIGHT/
LOW CLOUDS OVERSPREAD ALL AREAS EAST OF THE BLUE RIDGE THIS
MORNING IN RESPONSE TO THE AREA OF LOW PRESSURE DEVELOPING OFF
THE CAROLINA COASTLINE. SHOWER CHANCES WILL INCREASE GRADUALLY
THIS MORNING AS MOISTURE STREAMS IN FROM THE SOUTHEAST, BUT
MAINLY SOUTHEAST OF THE I-95 CORRIDOR. HOWEVER, AT LEAST SOME
SPOTTY SHOWERS OR DRIZZLE COULD REACH AS FAR WEST AS THE BLUE
RIDGE. GIVEN THE DRY AIR MASS IN PLACE, MUCH OF THE INITIAL
ACTIVITY MAY BE LOST TO EVAPORATION. EVENTUALLY THOUGH, DO
EXPECT THESE TO PRODUCE AT LEAST SOME LIGHT MEASURABLE
PRECIPITATION IN SOUTHERN MD AT A MINIMUM.
CLOUD COVER REMAINS OVER AREAS EAST OF THE BLUE RIDGE, BUT
THESE WILL EDGE EASTWARD IN TIME. SOME LATE DAY SUNSHINE IS
POSSIBLE ACROSS THE I-95 CORRIDOR. HIGH TEMPERATURES ARE
FORECAST TO REMAIN IN THE LOW/MID 70S (60S IN THE MOUNTAINS).
OVERNIGHT LOWS DROP INTO THE 50S, WITH SOME MID/UPPER 40S
POSSIBLE OVER THE CENTRAL SHENANDOAH VALLEY BACK INTO THE
POTOMAC HIGHLANDS.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/
HIGH PRESSURE RETURNS ON THURSDAY AND FRIDAY WITH MOSTLY SUNNY
SKIES AND TEMPERATURES ACTUALLY RETURNING CLOSER TO AVERAGE FOR
THIS TIME OF YEAR, WITH HIGHS IN THE 70S TO LOW 80S. WINDS
REMAIN LIGHT AND OUT OF THE N TO NNE DURING THIS TIME AS WELL.
EXPECT SOME PATCHY FOG TO DEVELOP IN THE TYPICAL SHELTERED
VALLEYS AND AREAS THAT FAVOR RADIATIONAL COOLING OVERNIGHT. LOW
TEMPERATURES WILL GENERALLY BE IN THE 50S FOR MOST, WITH LOW 60S
ALONG THE WATER AND IN THE METROS.
LONG TERM /SATURDAY THROUGH TUESDAY/
UPPER LEVEL TROUGHING PIVOTS OVER THE EAST COAST THROUGHOUT THE
WEEKEND AS SURFACE HIGH PRESSURE BUILDS OVER THE MID-ATLANTIC. MODEL
GUIDANCE DIVERGES AS WE HEAD INTO THE WORK WEEK, WITH THE GFS AND
ECMWF DEVELOPING A CUT-OFF LOW OVERHEAD WHILE THE CANADIAN MAINTAINS
UPPER LEVEL TROUGHING. AT THE SURFACE, A COLD FRONT PUSHING THROUGH
THE FORECAST AREA WILL BRING INCREASED PRECIPITATION CHANCES TO THE
AREA MONDAY EVENING. CONDITIONS DRY OUT TUESDAY AS SURFACE HIGH
PRESSURE RETURNS OVERHEAD. HIGH TEMPERATURES WILL BE IN THE 70S TO
LOW 80S EACH DAY WITH OVERNIGHT LOW TEMPERATURES IN THE 50S TO LOW
60S.
AVIATION /08Z WEDNESDAY THROUGH SUNDAY/
AS EXPECTED, SEEING LOW CLOUDS START TO PUSH EAST IN RESPONSE TO
ONSHORE FLOW AROUND AN APPROACHING AREA OF LOW PRESSURE TO OUR
SOUTHEAST. MVFR CEILINGS ARE MOST LIKELY ACROSS THE METRO
TERMINALS, WITH A BIT MORE UNCERTAINTY TOWARD CHO AND MRB. MOST
GUIDANCE KEEPS IFR CEILINGS TO THE EAST OF ALL TERMINALS, BUT
IT COULD BE CLOSE FOR BWI AND MTN, SO MAINTAINING AT LEAST A SCT
GROUPS AROUND 800 FT FOR MUCH OF THE DAY TODAY. ADDITIONALLY,
THREW IN SOME PROB30 GROUPS EARLY THIS MORNING FOR THE CHANCE OF
A FEW SHOWERS, THOUGH THERE IS STILL LOTS OF UNCERTAINTY WITH
HOW MUCH REACHES THE SURFACE.
NORTHERLY WINDS MAY GUST 15-20 KT AT TIMES THROUGH THE DAY.
THERE'S A BIT MORE UNCERTAINTY WITH HOW QUICKLY CEILINGS ERODE
AS THE LOW MOVES FARTHER OFF THE COAST. HOWEVER, VFR MAY NOT
RETURN AREA- WIDE UNTIL THURSDAY MORNING.
VFR CONDITIONS AND LIGHT WINDS OUT OF THE N TO NNE CAN BE
EXPECTED ON THURSDAY AND FRIDAY.
EAST WINDS ON SATURDAY SHIFT TO WEST/NORTHWEST ON SUNDAY WITH VFR
CONDITIONS EXPECTED BOTH DAYS.
MARINE
ENHANCED NNE WINDS CONTINUE TODAY AS LOW PRESSURE TRACKS UP THE
EAST COAST AND HIGH PRESSURE REMAINS ANCHORED TO THE NORTH. AS A
RESULT, SCAS CONTINUE THROUGH THE DAY TODAY AND SHOULD GRADUALLY
TAPER OFF THIS EVENING FOR THE BAY AND LOWER TIDAL POTOMAC
ZONES. FOR THE UPPER/MIDDLE TIDAL POTOMAC, WIND GUSTS WILL
LIKELY BE RIGHT ALONG THE ADVISORY THRESHOLD, ESPECIALLY AFTER
SUNRISE WEDNESDAY. SOME SHOWERS CAN BE EXPECTED AS WELL AS THE
AREA OF LOW PRESSURE SLIDES BY.
WINDS FINALLY START TO DIMINISH THIS EVENING AS THE
AFOREMENTIONED AREA OF LOW PRESSURE PUSHES AWAY FROM THE REGION,
BUT SOME GUSTS MAY LINGER ON THE WIDER WATERS.
SUB-SCA NORTHERLY WINDS ARE EXPECTED THURSDAY AND FRIDAY AS
CANADIAN HIGH PRESSURE TAKES CONTROL YET AGAIN.
EAST WINDS ON SATURDAY SHIFT TO SOUTHEAST OVER THE WATERS ON SUNDAY.
WINDS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA BOTH DAYS.
TIDES/COASTAL FLOODING
DUE TO LOW PRESSURE MOVING OFF THE COAST AND THE RECENT FULL
MOON, TIDES WILL REMAIN ELEVATED IN THE COMING DAYS. NE WINDS
DURING THE MIDDLE OF THE WEEK MAY ASSIST IN LOCKING IN HIGHER
WATER LEVELS AND PUSHING THE WATER TOWARD THE WESTERN SHORE.
ALEXANDRIA, ANNAPOLIS, AND DAHLGREN ARE MOST LIKELY TO REACH
MINOR FLOOD STAGE, BUT SOME OTHER LOCATIONS MAY BE CLOSE.
ADDITIONAL MINOR FLOODING COULD OCCASIONALLY BE AN ISSUE
THROUGH THE END OF THE WEEK WITH NO REAL PATTERN CHANGE IN
SIGHT.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR MDZ008.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
ANZ530>534-537>543.
SYNOPSIS...CJL
NEAR TERM...ADS/CJL
SHORT TERM...ADS/CJL
LONG TERM...AVS
AVIATION...ADS/AVS/CJL
MARINE...ADS/AVS/CJL
TIDES/COASTAL FLOODING...LWX
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