696
FXUS61 KLWX 300759
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
359 AM EDT SUN MAR 30 2025
SYNOPSIS
A BACKDOOR FRONT WILL DROP INTO NORTHEASTERN MARYLAND THIS MORNING,
ATTACHED TO A LARGER STALLED FRONT WAVERING OVER PENNSYLVANIA AND
NEW JERSEY. ONCE THIS FRONT LIFTS BACK NORTH THIS AFTERNOON, IT
SHOULD REMAIN OVER SOUTHERN NEW YORK THROUGH TONIGHT. MEANWHILE,
HIGH PRESSURE WILL REMAIN ANCHORED OFFSHORE NEAR BERMUDA, WHILE
MULTIPLE WAVES OF LOW PRESSURE DEVELOP AND MOVE FROM THE CENTRAL
PLAINS AND MISSISSIPPI RIVER VALLEY TOWARD THE MIDWEST AND GREAT
LAKES. A COLD FRONT APPROACHING FROM THE OHIO RIVER VALLEY WILL
CROSS THE MID-ATLANTIC MONDAY AFTERNOON AND EVENING, PULLING
OFFSHORE BY TUESDAY MORNING. HIGH PRESSURE WILL BRIEFLY RETURN
TUESDAY INTO WEDNESDAY. ANOTHER SYSTEM WILL APPROACH THURSDAY,
THEN MEANDER NEARBY INTO NEXT WEEKEND.
NEAR TERM /THROUGH TONIGHT/
AN IMPRESSIVE BACKDOOR FRONT HAS MADE ITS WAY INTO NORTHEASTERN
MARYLAND EARLY THIS MORNING. IT SHOULD CONTINUE SOUTHWESTWARD
THROUGH ROUGHLY THE BALTIMORE METRO AREA BEFORE WASHING OUT AND
RETREATING NORTHWARD LATER THIS MORNING INTO THIS AFTERNOON.
OTHERWISE, WIDESPREAD MID AND HIGH LEVEL CLOUDS REMAIN OVER THE
REGION THANKS TO INCREASING MOISTURE AND A WEAK LEAD IMPULSE
AHEAD OF TROUGHING OVER THE MIDDLE OF THE COUNTRY. SOME BREAKS
IN THE CLOUDS WILL LIKELY DEVELOP AT TIMES INTO THIS AFTERNOON,
BUT MORE CLOUDS THAN SUN ARE EXPECTED OVERALL.
DESPITE THE CLOUDS, CONTINUED SOUTH/SOUTHWEST FLOW WILL ALLOW
TEMPERATURES TO RISE WELL INTO THE 70S TO AROUND 80 (WITH 60S
OVER MOUNTAIN LOCALES).
GIVEN LOW-LEVEL DRY AIR IN PLACE, IT LOOKS LIKE A LOT OF RAIN
SHOWER ACTIVITY SHOULD HOLD OFF FOR MUCH OF THE AREA UNTIL
TONIGHT, THOUGH A FEW SPRINKLES OR A POP UP SHOWER ARE POSSIBLE
TODAY MAINLY NEAR AND WEST OF THE BLUE RIDGE/CATOCTIN MOUNTAINS.
A GRADUAL UPTICK IN SHOWER ACTIVITY IS POSSIBLE TONIGHT AS
ANOTHER WAVE PASSES OVERHEAD AND LOW-LEVEL MOISTURE CONTINUES
TO INCREASE. AMOUNTS SHOULD BE LIGHT, LESS THAN 0.10", THOUGH A
REMNANT LINE OF CONVECTION MAY APPROACH THE APPALACHIAN CREST
AROUND DAYBREAK SUNDAY.
TEMPERATURES TONIGHT ARE ONLY EXPECTED TO DROP BACK INTO THE 60S
(50S MOUNTAINS), ROUGHLY 20 DEGREES ABOVE NORMAL FOR LATE MARCH.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/
BROAD TROUGHING OVER THE MS VALLEY WILL PUSH EASTWARD MONDAY,
UNDERGOING AMPLIFICATION AIDED BY A COMPACT UPPER LOW DIVING
SOUTH OVER THE SOUTHERN HUDSON/JAMES BAY VICINITY IN CANADA.
EMBEDDED WITHIN THIS TROUGH WILL BE A SHORTWAVE AND ATTENDANT
SURFACE LOW MOVING UP THE ST. LAWRENCE VALLEY, WITH ANOTHER
SHORTWAVE/SURFACE LOW PRESSING ACROSS THE TN VALLEY TOWARD/JUST
IN THE LEE OF THE APPALACHIANS THROUGH THE DAY. A STRONG COLD
FRONT WILL CONNECT THESE FEATURES, PRESSING WEST TO EAST FROM
MIDDAY THROUGH LATE EVENING.
BAROCLINICITY WILL SHARPEN ALONG THE SURFACE COLD FRONT,
ESPECIALLY AS IT CROSSES I-81 AND THE BLUE RIDGE/CATOCTIN
MOUNTAINS BY MID TO LATE AFTERNOON. THIS HAPPENS AS THE
AFOREMENTIONED TRAILING WAVE APPROACHES FROM THE TN VALLEY, AND
THE UPPER JET TAKES ON A SLIGHT NEGATIVE TILT PLACING THE AREA
IN ITS RIGHT ENTRANCE REGION BY MONDAY EVENING.
ALTHOUGH STRONG LINEAR FORCING IS EXPECTED ALONG THE APPROACHING
COLD FRONT, SHEAR/STORM MOTION VECTORS AREN'T EXACTLY PARALLEL,
AND MULTIPLE WAVES RIDING ALONG THE FRONT AT BOTH THE SURFACE
AND ALOFT WILL LIKELY MODULATE THE ENVIRONMENT ON THE MESOSCALE.
A MIXED CONVECTIVE MODE IS MOST LIKELY AS A RESULT. EVOLUTION
OF THESE SMALLER FEATURES IS A BIT UNCERTAIN AND IS TIED AT
LEAST IN PART TO PRIOR CONVECTION. BUT, LOCALLY BACKED/ENHANCED
LOW-LEVEL FLOW IN THEIR VICINITY COULD ENHANCE MORE VIGOROUS
UPDRAFTS AND RESULT IN A MORE FAVORABLE LOW-LEVEL SHEAR
ENVIRONMENT. THIS WOULD LEAD TO THE POTENTIAL FOR SEMI-DISCRETE
SUPERCELL THUNDERSTORMS WITH AN ACCOMPANYING HAIL AND TORNADO
RISK, IN ADDITION TO A DAMAGING WIND RISK WITH ANY BOWS/LEWPS
WITHIN BROADER BANDS OF THUNDERSTORMS.
IF THE UPPER TROUGH IS MORE AMPLIFIED MONDAY EVENING, THIS COULD
SLOW THE FRONT'S EASTWARD PROGRESS FOR A TIME. THIS MAY RESULT
IN MULTIPLE ROUNDS OF STORMS AND ADDITIONAL (BENEFICIAL) RAIN.
WINDS WILL TURN NORTHWEST AND MUCH COLDER AIR WILL BE USHERED IN
LATE MONDAY NIGHT INTO TUESDAY AS CONDITIONS CLEAR.
LONG TERM /WEDNESDAY THROUGH SATURDAY/
AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CENTRAL CONUS ON
WEDNESDAY BEFORE TRACKING ACROSS THE GREAT LAKES AND INTO CANADA
THURSDAY THROUGH THE END OF THE WEEK. AS THE AREA OF LOW PRESSURE
TRACKS TO OUR NORTH, THE ASSOCIATED WARM FRONT WILL LIFT THROUGH THE
FORECAST AREA ON WEDNESDAY BEFORE THE ASSOCIATED COLD FRONT
APPROACHES AND STALLS OVER THE MID ATLANTIC FRIDAY. PRECIPITATION
CHANCES INCREASE FOR THOSE ALONG AND WEST OF THE ALLEGHENIES ON
WEDNESDAY, AS THE FRONTAL BOUNDARY APPROACHES, WITH MOST OF THE AREA
EXPECTED TO REMAIN DRY. THERE IS A SLIGHT CHANCE TO A CHANCE OF
PRECIPITATION AREAWIDE THURSDAY THROUGH SATURDAY.
HIGH TEMPERATURES ON WEDNESDAY WILL BE IN THE UPPER 50S TO 60S WITH
OVERNIGHT LOW TEMPERATURES EXPECTED TO BE IN THE 50S FOR MOST.
THURSDAY WILL BE THE WARMEST DAY OF THE PERIOD IN THE WAKE OF A WARM
FRONT AND WITH SOUTHERLY FLOW AS HIGH PRESSURE SHIFTS OFFSHORE. HIGH
TEMPERATURES WILL SOAR INTO THE UPPER 70S TO LOW 80S WITH THOSE IN
THE MOUNTAINS STAYING IN THE UPPER 60S. OVERNIGHT LOW TEMPERATURES
WILL BE IN THE MID 50S TO MID 60S. TEMPERATURES WILL GRADUALLY COOL
DOWN FOR THE SECOND HALF OF THE LONG TERM PERIOD WITH HIGH
TEMPERATURES IN THE 60S TO 70S. OVERNIGHT LOW TEMPERATURES WILL BE
IN THE 40S TO 50S.
AVIATION /08Z SUNDAY THROUGH THURSDAY/
VFR CONDITIONS ARE EXPECTED, THOUGH SOME BRIEF LOWER CIGS ARE
POSSIBLE NEAR MTN AND PERHAPS BWI NEAR A BACKDOOR FRONT THIS
MORNING. WINDS NEAR THIS BACKDOOR FRONT WILL BE MORE E/NE. S/SW
FLOW IS EXPECTED OTHERWISE THROUGH MONDAY WITH GUSTS OF 15-25
KTS AT TIMES. STRONG TO SEVERE THUNDERSTORMS ARE LIKELY IN
ASSOCIATION WITH A STRONG COLD FRONT MONDAY INTO MONDAY EVENING.
SUB-VFR IS LIKELY AT TIMES BOTH EARLY MONDAY WITH LOWER CIGS,
AND WITH ANY CONVECTION LATER IN THE DAY. VFR/NW FLOW RETURNS
BEHIND THE FRONT LATE MONDAY NIGHT THROUGH TUESDAY NIGHT.
SUB-VFR CONDITIONS ARE POSSIBLE WEDNESDAY WITH SE WINDS GUSTING 15
TO 25 KNOTS. PRECIPITATION IS POSSIBLE AT KMRB IN THE EVENING. ON
THURSDAY, SW WINDS GUST 15 TO 20 KNOTS IN THE AFTERNOON AS
PRECIPITATION CHANCES BRING POSSIBLE SUB-VFR CONDITIONS TO ALL
TERMINALS.
MARINE
BOUTS OF SOUTHERLY FLOW GUSTING 20-25 KTS IS EXPECTED AT TIMES
THROUGH MONDAY AHEAD OF AN APPROACHING STRONG COLD FRONT. WINDS
WILL TURN NW WITH CONTINUED GUSTINESS IN THE WAKE OF THE FRONT
AND STRONG TO SEVERE STORMS MONDAY EVENING/NIGHT, WITH A SLOW
SUBSIDING OF WINDS THROUGH TUESDAY.
SOUTHEASTERLY WINDS ON WEDNESDAY SHIFT TO SOUTHWESTERLY ON THURSDAY.
SCA CRITERIA WINDS ARE POSSIBLE WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON.
TIDES/COASTAL FLOODING
SENSITIVE TIDAL LOCATIONS SUCH AS BALTIMORE, ANNAPOLIS, AND HAVRE DE
GRACE MAY REACH ACTION STAGE AS A STRONG COLD FRONT APPROACHES THE
WATERS. STRONG SOUTHERLY FLOW WILL LEAD TO INCREASED TIDAL ANOMALIES
AHEAD OF THE FRONTAL PASSAGE, WITH ANOMALIES PEAKING ON MONDAY.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON TODAY TO NOON EDT TUESDAY FOR
ANZ530>543.
SYNOPSIS...DHOF
NEAR TERM...DHOF
SHORT TERM...DHOF
LONG TERM...AVS
AVIATION...AVS/DHOF
MARINE...AVS/DHOF
TIDES/COASTAL FLOODING...
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