750
FXUS61 KLWX 211913
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
313 PM EDT SAT MAR 21 2026
WHAT HAS CHANGED
NO MAJOR CHANGES WERE MADE TO THE PREVIOUS FORECAST.
KEY MESSAGES
-1) TEMPERATURES WARM THROUGH THE WEEKEND WITH A COLD FRONT
BRINGING SHOWERS AND A CHANCE FOR SEVERE THUNDERSTORMS LATE
SUNDAY.
-2) QUIET WEATHER AND COOL TEMPERATURES THROUGH
WEDNESDAY BEFORE A COLD FRONT BRINGS RENEWED RAIN CHANCES LATE WEEK.
DISCUSSION
KEY MESSAGE 1...TEMPERATURES WARM THROUGH THE WEEKEND WITH A
COLD FRONT BRINGING SHOWERS AND A CHANCE FOR SEVERE THUNDERSTORMS
LATE SUNDAY.
SKIES HAVE CLEARED OUT ACROSS MOST OF THE FORECAST AREA THIS
AFTERNOON IN THE WAKE OF A COLD FRONT THAT PASSED THROUGH THIS
MORNING. JUST A FEW FAIR WEATHER CUMULUS CLOUDS REMAIN, MOSTLY
TIED TO TERRAIN CIRCULATIONS THAT HAVE FORMED OVER THE
MOUNTAINS. NORTHERLY FLOW BEHIND THE FRONT HAS ADVECTED COOLER,
BUT STILL WELL ABOVE AVERAGE TEMPERATURES INTO THE AREA.
TEMPERATURES ARE NEARING THEIR HIGHS FOR THE DAY IN THE 60S TO
LOWER 70S (50S MOUNTAINS).
WINDS WILL SHIFT TO OUT OF THE EAST THIS EVENING, AND THEN
SOUTH LATER TONIGHT. AS LOW-LEVEL MOISTURE STARTS TO INCREASE
WITHIN SOUTHERLY FLOW, THERE ARE SOME HINTS THAT LOW CLOUDS
AND/OR FOG MAY TRY TO FORM LATER TONIGHT, ESPECIALLY TO THE EAST
OF THE BLUE RIDGE. TEMPERATURES WILL REMAIN MILD OVERNIGHT, WITH
LOWS IN THE MID 40S TO MID 50S.
ANY LOW CLOUDS OR FOG SHOULD BURN OFF QUICKLY TOMORROW MORNING.
MUCH WARMER AIR WILL ADVECT INTO THE AREA TOMORROW IN
SOUTHWESTERLY FLOW ALOFT, WITH 850 HPA TEMPERATURES SURGING TO
AROUND 14-17 C. STRONG DAYTIME HEATING WILL LEAD TO DEEP MIXING,
ENABLING TEMPERATURES TO NEAR RECORD VALUES FOR LATE MARCH. MOST
OF THE FORECAST AREA SHOULD CLIMB INTO THE 80S, WITH SOME
LOCATIONS POTENTIALLY EVEN MAKING IT INTO THE MID-UPPER 80S.
A STRONG COLD FRONT WILL START TO PROGRESS SOUTHWARD ACROSS PA
DURING THE AFTERNOON HOURS TOMORROW. SHOWERS AND STORMS ARE
EXPECTED TO DEVELOP ALONG THE FRONT DURING THE MID-LATE AFTERNOON
HOURS. FURTHER SOUTH, MODEL SOUNDINGS SHOW SIGNS OF CAPPING
WITH A REMNANT ELEVATED MIXED LAYER MOVING IN ALOFT. THIS SHOULD
HELP TO PREVENT THE DEVELOPMENT OF STORMS AHEAD OF THE FRONT,
WHICH WILL KEEP CONDITIONS DRY THROUGH NEARLY ALL OF THE DAY IN
OUR FORECAST AREA. THE STORMS OVER PA WILL LIKELY DRIFT
SOUTHEASTWARD TOWARD NORTHERN MARYLAND AROUND OR SHORTLY AFTER
DARK. AS LOW- LEVELS STABILIZE WITH LOSS OF DAYTIME HEATING, THE
TREND SHOULD BE FOR THESE STORMS TO GRADUALLY WEAKEN AS THEY
MOVE INTO OUR FORECAST AREA AFTER DARK.
THE ENVIRONMENT TO OUR NORTH TOMORROW ACROSS PA LOOKS VERY
FAVORABLE FOR THE DEVELOPMENT OF SEVERE THUNDERSTORMS, WITH A
CAPE/SHEAR PARAMETER SPACE CAPABLE OF PRODUCING BOTH SUPERCELLS
AND BOWING SEGMENTS. IF THE TIMING/LOCATION OF THE FRONT WERE
TO TREND FASTER/FURTHER SOUTH, WE COULD GET STORMS IN THAT TYPE
OF ENVIRONMENT PRIOR TO STABILIZATION. AND EVEN IF STORMS DO
MOVE IN AFTER DARK, THEY COULD STILL POTENTIALLY PRODUCE SEVERE
HAIL, EVEN IF THEY'RE ELEVATED. TOMORROW IS CERTAINLY A DAY TO
WATCH FOR SEVERE THUNDERSTORMS, BUT AS IT STANDS NOW, IT MAY BE
A NEAR MISS FOR MOST OF THE AREA, WITH THE CAPPING SERVING AS A
POTENTIAL SAVING GRACE.
AS OF NOW, SPC HAS NORTHERN MARYLAND AND MOST OF THE EASTERN
PANHANDLE OF WEST VIRGINIA OUTLOOKED IN A SLIGHT RISK, AND THE
REST OF THE AREA OUTLOOKED IN A MARGINAL RISK. SPC ALSO HAS FAR
NORTHWESTERN PORTIONS OF THE FORECAST IN A SIG HAIL OUTLOOK
(INDICATING THE POTENTIAL FOR 2+" HAILSTONES). THAT HINTS AT THE
POTENTIAL HIGH CEILING FOR THE SEVERITY OF STORMS TOMORROW, IF
THEY MAINTAIN THEIR STRENGTH SOUTHWARD INTO OUR FORECAST AREA.
AS OF NOW, THE MOST LIKELY TIMING FOR STORMS LOOKS TO BE BETWEEN
7 PM AND MIDNIGHT, WITH REMNANT SHOWERS MOVING SOUTHWARD ALONG
WITH THE COLD FRONT THROUGH THE ENTIRE FORECAST AREA LATER
DURING THE OVERNIGHT HOURS.
WINDS WILL SHIFT TO OUT OF THE NORTHWEST BEHIND THE COLD FRONT
ON MONDAY. CONDITIONS WILL DRY OUT AND TEMPERATURES WILL BE MUCH
COOLER (BUT NEAR NORMAL), WITH HIGHS FOR MOST IN THE 50S AND
LOWER 60S (40S MOUNTAINS). WINDS WILL GUST TO AROUND 25-35 MPH
OUT OF THE NORTHWEST.
KEY MESSAGE 2...BENIGN WEATHER IS LIKELY DURING MID WEEK BEFORE
A COLD FRONT BRINGS HIGHER RAIN CHANCES THURSDAY NIGHT INTO
FRIDAY.
HIGH PRESSURE WILL BUILD OVERHEAD TUESDAY BEFORE MOVING OFF TO THE
EAST TUESDAY NIGHT AND WEDNESDAY. DRY WEATHER WILL PREVAIL THROUGH
THIS PERIOD BENEATH WEST-NORTHWEST FLOW ALOFT. BELOW NORMAL
TEMPERATURES ON TUESDAY WILL MODERATE WEDNESDAY AS LOW LEVEL FLOW
TURNS SOUTHERLY.
A WARM ADVECTION PATTERN CONTINUES WEDNESDAY NIGHT AND THURSDAY. A
SUBTLE SHORTWAVE MAY CROSS AROUND THIS TIME AND AID IN THE CHANCE
FOR SOME LIGHT SHOWERS. HOWEVER, DRY LOW LEVELS MAY LIMIT HOW MUCH
RAIN CAN REACH THE GROUND. THE BEST FORCING WILL REMAIN ALONG THE
ST. LAWRENCE VALLEY AS A SURFACE LOW CROSSES. IT'S POSSIBLE THIS LOW
MAY SHOVE THE FRONTAL ZONE SOUTHWARD OR STUNT IT FROM LIFTING
NORTHWARD. A SLIGHTLY DEEPER TROUGH WILL FOLLOW WITH ANOTHER LOW
TRACKING ALONG THE FRONT AROUND FRIDAY. THE FRONT WILL SAG SOUTHWARD
AS A COLD FRONT , BUT NOT TOO QUICKLY AS IT WILL BE SOMEWHAT
PARALLEL TO THE UPPER FLOW. THUS TIMING AND AMOUNTS OF ANY RAIN ARE
UNCERTAIN ALTHOUGH IT DOES LOOK TO PUSH SOUTH SATURDAY. THE POSITION
OF THIS POTENTIALLY WAVERING FRONTAL ZONE MAY HAVE SOME IMPACTS ON
TEMPERATURES THURSDAY AND FRIDAY, THOUGH THEY SHOULD BE NEAR OR
ABOVE NORMAL.
BY SATURDAY, HIGH PRESSURE OF CANADIAN ORIGIN WILL BE BUILDING IN
FROM THE NORTHWEST, BRINGING A RETURN TO NEAR TO BELOW NORMAL
TEMPERATURES.
AVIATION /18Z SATURDAY THROUGH THURSDAY/
VFR CONDITIONS AND LIGHT NORTHERLY WINDS ARE EXPECTED THIS
AFTERNOON. WINDS WILL SHIFT AROUND TO OUT OF THE EAST THIS
EVENING AND THEN SOUTH BY LATER TONIGHT. THERE ARE SOME SIGNS
THAT LOW CLOUDS AND/OR FOG MAY TRY TO FORM LATE TONIGHT AT MANY
OF THE TERMINALS. FOR NOW, TAFS HAVE BEEN KEPT MVFR, BUT IFR
CIGS ARE HINTED AT WITH A SCATTERED GROUP. ANY LOW CLOUDS OR FOG
SHOULD QUICKLY BURN OFF TOMORROW MORNING, LEADING TO VFR
CONDITIONS ONCE AGAIN THROUGH MUCH OF THE DAY TOMORROW. WINDS
WILL GRADUALLY PICK UP OUT OF THE SOUTHWEST, AND COULD GUST TO
AROUND 20-30 KNOTS DURING THE LATE AFTERNOON AND EVENING HOURS.
A COLD FRONT WILL APPROACH FROM THE NORTH TOMORROW NIGHT. AS
THAT COLD FRONT DROPS SOUTHWARD TOMORROW NIGHT, WINDS WILL
BECOME NORTHERLY BEHIND THE FRONT, AND CHANCES FOR SHOWERS AND A
FEW THUNDERSTORMS WILL INCREASE. SUB-VFR CEILINGS AND
VISIBILITIES MAY BOTH BE POSSIBLE AT TIMES TOMORROW NIGHT. ANY
PRECIPITATION SHOULD COME TO AN END BY DAYBREAK ON MONDAY, BUT
WINDS WILL REMAIN GUSTY (25-35 KNOTS) OUT OF THE NORTHWEST
DURING THE DAY MONDAY.
SIGNIFICANT WEATHER IS UNLIKELY TUESDAY AND WEDNESDAY AS HIGH
PRESSURE BUILDS ACROSS THE AREA. SOUTHERLY WINDS MAY GUST TO AROUND
20 KT ON THURSDAY AS A LOW PRESSURE SYSTEM PASSES WELL TO THE NORTH.
LOCALLY RAIN CHANCES WILL REMAIN MINIMAL.
MARINE
SUB-SCA LEVEL NORTHERLY WINDS ARE EXPECTED OVER THE WATERS THIS
AFTERNOON. WINDS SWITCH AROUND TO THE EAST THIS EVENING, AND
THEN SOUTH LATER TONIGHT, BUT REMAIN SUB-SCA IN NATURE. WINDS
GRADUALLY PICK UP OUT OF THE SOUTH TO SOUTHWEST THROUGH THE DAY
TOMORROW, AND COULD REACH LOW-END SCA LEVELS BY THE LATE
AFTERNOON/EVENING HOURS. HOWEVER, WARM AIR MOVING OVER MUCH
COOLER WATERS COULD LIMIT MIXING AND RESULTANT WIND SPEEDS,
ESPECIALLY OVER THE WIDER WATERS.
A STRONG COLD FRONT WILL MOVE OVER THE WATERS TOMORROW NIGHT,
CAUSING WINDS TO SHIFT TO OUT OF THE NORTH. SHOWERS AND A FEW
THUNDERSTORMS MAY ACCOMPANY THE FRONTAL PASSAGE TOMORROW EVENING
INTO TOMORROW NIGHT, WITH THE BEST CHANCE FOR STORMS ACROSS
NORTHERN PORTIONS OF THE BAY. SMWS MAY BE NEEDED TOMORROW
EVENING INTO EARLY TOMORROW NIGHT AS STORMS MOVE OVER THE
WATERS. CHANCES FOR PRECIPITATION WILL COME TO AN END BY
DAYBREAK MONDAY, BUT WINDS WILL REMAIN GUSTY OUT OF THE
NORTHWEST THROUGH THE DAY. SCAS WILL LIKELY BE NEEDED SUNDAY
NIGHT THROUGH THE DAY MONDAY.
HIGH PRESSURE WILL PROVIDE LIGHT WINDS TUESDAY. SOUTHWEST WINDS MAY
BEGIN TO INCREASE TUESDAY NIGHT INTO WEDNESDAY AS THE HIGH DEPARTS.
HOWEVER, ADVISORY LEVEL WINDS MAY HOLD OFF UNTIL WEDNESDAY NIGHT
INTO THURSDAY AS A LOW PRESSURE SYSTEM PASSES WELL NORTH OF THE
AREA.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
DISCUSSION...ADS/KJP
AVIATION...ADS/KJP
MARINE...ADS/KJP
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