365
FXUS61 KLWX 131420
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1020 AM EDT TUE OCT 13 2026
WHAT HAS CHANGED
NO MAJOR CHANGES TO THE CURRENT FORECAST PACKAGE OUTSIDE OF SUBTLE
ADJUSTMENTS OF PRECIPITATION CHANCES WEDNESDAY AFTERNOON AND EVENING
AS A FRONT PASSES THROUGH.
KEY MESSAGES
- 1) NEAR RECORD WARMTH AND MAINLY DRY CONDITIONS CONTINUE
THROUGH WEDNESDAY.
- 2) A STRONG FRONT MOVES THROUGH THE REGION LATE WEEK,
BRINGING STRONG WINDS AND COLD CONDITIONS.
DISCUSSION
KEY MESSAGE 1...DRY AND VERY WARM THROUGH WEDNESDAY.
WEAK HIGH PRESSURE AND MID-LEVEL RIDGING WILL CONTINUE TO DOMINATE
THE FORECAST HEADING INTO THE MIDWEEK PERIOD. THE HIGH ITSELF WILL
SLIDE OFFSHORE LATER TODAY ALLOWING THE MID-LEVEL RIDGE TO BUCKLE
HEADING INTO WEDNESDAY. MEANWHILE, A SERIES OF SHORTWAVE
DISTURBANCES WILL QUICKLY SLIDE FROM WEST TO EAST ACROSS NORTHERN
PORTIONS OF THE FORECAST REGION AS A COLD FRONT DROPS SOUTH FROM THE
GREAT LAKES AND OHIO RIVER VALLEY. THIS FRONT WILL TOUCH OFF SHOWERS
AND PERHAPS A FEW THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING,
MAINLY IN AREAS ALONG AND NORTH OF I-66/US-50 AND US-48. A MARGINAL
RISK (LEVEL 1 OUT OF 5) FOR SEVERE WEATHER IS IN PLACE FOR PORTIONS
OF WESTERN MD, EASTERN WV, AND THE VA HIGHLANDS WEDNESDAY AFTERNOON
WHERE BETTER INSTABILITY WILL RESIDE. COVERAGE OVERALL WILL BE
ISOLATED TO SCATTERED WITH DAMAGING WINDS AS THE PRIMARY CONCERN.
MOST LOCATIONS WILL REMAIN DRY THROUGH WEDNESDAY AFTERNOON GIVEN THE
TIMING OF THE FRONT AND RESIDUAL DRY AIR TO WORK WITH AS THE RIDGE
SLOWLY BUCKLES.
BEFORE THE FRONT ARRIVES, EXPECT NEAR RECORD WARMTH THIS AFTERNOON
AND AGAIN WEDNESDAY. HIGHS TODAY WILL REACH INTO THE LOW TO MID 80S
(MID 70S MOUNTAINS). LOWS TONIGHT WILL FALL BACK INTO THE UPPER 50S
AND MID 60S. HIGHS WEDNESDAY WILL BE MUCH WARMER IN THE MID TO UPPER
80S AND POTENTIALLY LOW 90S FOR AREAS SOUTH AND EAST OF DC.
COOLER CONDITIONS RETURN BRIEFLY THURSDAY AS MORE OF A WEDGE LIKE
PATTERN SETTLES IN. THIS IS DUE TO A LARGE SURFACE HIGH PRESSURE
SYSTEM ANCHORED OVER SOUTHERN ONTARIO THURSDAY WEDGING SOUTH ALONG
THE EASTERN FACE OF THE APPALACHIANS. EXPECT CLOUDY CONDITIONS
TO PREVAIL ALONG WITH PASSING SHOWERS ESPECIALLY ACROSS THE
SOUTHERN 2/3RDS OF THE FORECAST REGION. HIGHS WILL RETURN CLOSER
TO NORMAL WITH MOST LOCATIONS IN THE MID TO UPPER 60S. THE CAD
WILL QUICKLY ERODE THURSDAY NIGHT INTO FRIDAY AHEAD OF THE NEXT
FRONT HEADING INTO THE WEEKEND.
KEY MESSAGE 2...A STRONG FRONT MOVES THROUGH THE REGION LATE
WEEK, BRINGING STRONG WINDS AND COLD CONDITIONS.
A LOW PRESSURE SYSTEM IS FORECAST TO TRACK FROM THE GREAT LAKES
REGION INTO CANADA THURSDAY NIGHT INTO FRIDAY, PUSHING A COLD FRONT
ACROSS THE FORECAST AREA ON FRIDAY. THIS FRONTAL SYSTEM BRINGS
INCREASED PRECIPITATION CHANCES ACROSS THE FORECAST AREA THURSDAY
AND FRIDAY, WITH A FEW RUMBLES OF THUNDER POSSIBLE AS THE COLD FRONT
PUSHES THROUGH ON FRIDAY. ADDITIONALLY, HIGH TEMPERATURES IN THE 60S
TO LOW 80S COOL TO THE 40S AND 50S ON SATURDAY AS NOTICEABLY COLDER
AIR MOVES IN. BEHIND THE FRONT, TEMPERATURES PLUMMET INTO THE 30S
FOR MOST SATURDAY NIGHT WITH ONLY THE METRO AREAS STAYING IN THE LOW
40S. TEMPERATURES WILL GRADUALLY WARM ON SUNDAY WITH HIGHS IN THE
50S TO LOW 60S AND OVERNIGHT LOWS IN THE UPPER 30S TO 40S.
BEHIND THE FRONTAL SYSTEM, SURFACE HIGH PRESSURE BUILDS OVER THE
CENTRAL CONUS BEGINNING ON FRIDAY BEFORE SHIFTING EASTWARD. A TIGHT
PRESSURE GRADIENT BETWEEN THE SURFACE HIGH AND THE DEPARTING LOW
PRESSURE SYSTEM LEADS TO WINDY CONDITIONS ACROSS THE FORECAST AREA
FRIDAY NIGHT INTO SATURDAY. NORTHWEST WINDS GUST 20 TO 30 MILES PER
HOUR , WITH HIGHER ELEVATIONS GUSTING UP TO 40 MPH. WIND HEADLINES
MAY BE NEEDED ACROSS THE HIGHER ELEVATIONS BUT WE WILL CONTINUE TO
MONITOR.
IT'S ALSO WORTH MENTIONING THAT WITH GUSTY NORTHWEST WINDS, UPSLOPE
SNOW SHOWERS ARE POSSIBLE ALONG THE ALLEGHENIES LATE FRIDAY NIGHT
INTO SATURDAY MORNING. WHILE SNOW SHOWERS ARE UNLIKELY, A RAIN/SNOW
MIX CANNOT BE RULED OUT. LITTLE TO NO ACCUMULATION IS EXPECTED
ALTHOUGH THE FIRST FLAKES OF THE SEASON ARE POSSIBLE.
AVIATION /14Z TUESDAY THROUGH SATURDAY/
VFR CONDITIONS EXPECTED FOR THE REMAINDER OF TODAY THROUGH WEDNESDAY
AFTERNOON AS WEAK HIGH PRESSURE RESIDES NEARBY. A FRONT WILL DROP
INTO THE AREA FROM THE NORTH WEDNESDAY AFTERNOON AND EVENING
BRINGING SPOTTY TO SCATTERED SHOWERS AND THUNDERSTORMS. THIS WILL
LEAD TO BRIEF SUB-VFR REDUCTIONS BETWEEN 20-03Z/4-11PM IN
THUNDERSTORM ACTIVITY IS LOW OVER THE CORRIDOR WITH HIGH
THUNDERSTORM PROBABILITIES OF 25 PERCENT OR GREATER MAINLY WEST OF
MRB. THE FRONT DROPS SOUTH OF THE REGION THURSDAY BEFORE STALLING IN
THE VICINITY OF SOUTHEAST AND SOUTHWEST VA. THIS WILL PUT US IN MORE
OF A WEDGE LIKE PATTERN WITH ON AND OFF SHOWERS AND WIDESPREAD
SUB- VFR CONDITIONS AT MOST OF THE TERMINALS. WINDS WILL REMAIN
OUT OF THE SOUTH TODAY AT 5 TO 10 KTS WITH OCCASIONAL GUSTS UP
TO 20 KTS. SOUTH WINDS CONTINUE TONIGHT INTO WEDNESDAY AT LESS
THAN 10 KTS. WINDS WILL SWITCH TO THE NORTH AND NORTHEAST
THURSDAY AT LESS THAN 15 KTS IN THE WAKE OF THE FRONTAL
BOUNDARY.
ON FRIDAY, SUB-VFR CONDITIONS ARE POSSIBLE ACROSS ALL TERMINALS AS A
COLD FRONT MOVES ACROSS THE FORECAST AREA, BRINGING PRECIPITATION.
ADDITIONALLY, SOUTH WINDS IN THE MORNING SHIFT TO NORTHWESTERLY BY
THE EVENING GUSTING 20 TO 30 KNOTS. VFR CONDITIONS ARE EXPECTED ON
SATURDAY WITH NORTHWEST WINDS CONTINUING TO GUST 20 TO 30 KNOTS.
MARINE
SOUTH WINDS AROUND 10-15 KNOTS ARE EXPECTED TODAY ACROSS THE WATERS.
SOUTHERLY CHANNELING EFFECTS COULD BRING GUSTS CLOSE TO SCA LEVELS
(AROUND 20 KNOTS), BUT THIS LIKELY WON'T BE FOR A LONG ENOUGH PERIOD
TO REQUIRE A SMALL CRAFT ADVISORY. INSTEAD, MARINE WEATHER
STATEMENTS ARE MORE LIKELY TO BE ISSUED FOR SMALL CRAFTS TO EXERCISE
CAUTION.
WINDS DIMINISH TONIGHT INTO WEDNESDAY, WITH GENERALLY SUB-SCA
CONDITIONS. A FRONT MOVES SOUTH ACROSS THE WATERS THURSDAY MORNING,
AND THIS IS LIKELY TO BRING SCA CONDITIONS WITH GUSTS AROUND 20
KNOTS FOR SEVERAL HOURS. WINDS DO QUICKLY DIMINISH THURSDAY
AFTERNOON.
SOUTHERLY WINDS ON FRIDAY MORNING SHIFT TO NORTHWEST FRIDAY
AFTERNOON AND REMAIN OUT OF THE NORTHWEST ON SATURDAY. A STRONG
PRESSURE GRADIENT BETWEEN HIGH PRESSURE TO THE WEST AND LOW PRESSURE
TO THE NE WILL BRING GUSTY WINDS BOTH DAYS, WITH SCA CONDITIONS
EXPECTED. GALE FORCE WINDS ARE POSSIBLE OVER THE OPEN WATERS EACH
DAY.
TIDES/COASTAL FLOODING
SOUTH WINDS ON WEDNESDAY COULD RESULT IN ELEVATED WATER LEVELS AT
SENSITIVE LOCATIONS ALONG THE CHESAPEAKE BAY. THIS COULD RESULT IN
SEVERAL STATIONS REACHING ACTION STAGE, WITH ANNAPOLIS FORECAST TO
BE CLOSER TO MINOR TIDAL FLOODING DURING THE WEDNESDAY EVENING HIGH
TIDE. A SURGE OF OFFSHORE (NORTH) WINDS THURSDAY MORNING WILL BRING
WATER LEVELS BACK DOWN.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
DISCUSSION...AVS/EST/SRT
AVIATION...AVS/KRR/EST
MARINE...AVS/KRR
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