241  
FXUS61 KLWX 310055  
AFDLWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC  
855 PM EDT SUN MAR 30 2025  
   
SYNOPSIS
 
 
LOW PRESSURE WILL TRACK INTO THE GREAT LAKES TONIGHT, AND THEN  
ACROSS SOUTHERN CANADA TOMORROW, WITH A TRAILING COLD FRONT  
MOVING THROUGH THE AREA TOMORROW NIGHT. HIGH PRESSURE WILL BUILD  
TO OUR NORTH FOR TUESDAY AND WEDNESDAY, BEFORE ANOTHER STRONG  
AREA OF LOW PRESSURE TRACKS INTO THE WESTERN GREAT LAKES ON  
THURSDAY.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
RADAR IMAGERY AS OF 850 PM STILL DEPICTED ISOLATED TO SCATTERED  
LIGHT SHOWERS OUT OVER THE POTOMAC HIGHLANDS. THIS IS STARTING  
TO DECAY AT THIS POINT, AS WAS ANTICIPATED, AND IS ALSO LIFTING  
NORTHEAST INTO PA. LARGELY, THIS ONLY DROPPED ABOUT A TENTH OF  
AN INCH OR SO IN THE "HEAVIEST" OF SHOWERS. THIS WAS BECAUSE IT  
HAD TO FIGHT A LOT OF DRY AIR AT THE SURFACE.  
 
THIS ROUND OF SHOWERS SHOULD CLEAR THE AREA IN THE NEXT HOUR OR  
TWO, AS IT HAS BEEN A BIT SLOWER TO TRAVERSE THE REGION THAN  
INITIALLY THOUGHT. DRY CONDITIONS WILL RETURN AREAWIDE FOR THE  
FIRST HALF OF THE NIGHT. THE BULK OF THE FORECAST AREA SHOULD  
EXPERIENCE DRY CONDITIONS THROUGH THE SECOND HALF OF THE NIGHT  
AS WELL, BUT DECAYING SHOWERS AND THUNDERSTORMS FROM THE OHIO  
VALLEY MAY REACH, AND POTENTIALLY PASS OVER, THE ALLEGHENY FRONT  
JUST PRIOR TO DAYBREAK. ACTUALLY INCREASED POPS A BIT WITH THIS  
MORNING ROUND IN THE LATEST FORECAST UPDATE. STILL ONLY AROUND  
30 TO 50 POPS, MAINLY IN THE NORTH. ADDITIONALLY, A STIFF  
SOUTHERLY BREEZE AND CLOUDS WILL KEEP TEMPERATURES VERY WARM  
OVERNIGHT, WITH LOWS IN THE 60S FOR MOST (50S IN THE MOUNTAINS).  
 

 
   
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/
 
 
EVENING UPDATE: NO SIGNIFICANT CHANGES WERE MADE TO THE TIMING  
OF THUNDERSTORMS TOMORROW, BUT DID ADD IN SOME ENHANCED WORDING  
TO INCLUDE DAMAGING WIND THREAT IN THE FORECAST TEXT. NO REAL  
CHANGES OTHERWISE, SO PLEASE REFER TO THE PREVIOUS DISCUSSION  
BELOW.  
 
A POTENT SHORTWAVE AND ITS ASSOCIATED STRONG AREA OF LOW  
PRESSURE WILL CONTINUE TO LIFT NORTHEASTWARD ACROSS ONTARIO AND  
QUEBEC TOMORROW, WHILE A TRAILING SHORTWAVE TRACKS FROM OK/AR  
TOMORROW MORNING TOWARD THE CENTRAL APPALACHIANS TOMORROW  
EVENING. A TRAILING COLD FRONT WILL EXTEND SOUTHWESTWARD FROM  
THE LOW OVER SOUTHERN CANADA, AND TRACK ACROSS THE FORECAST AREA  
FROM WEST TO EAST DURING THE FIRST HALF OF TOMORROW NIGHT.  
 
WHILE SOME QUESTIONS REMAIN REGARDING HOW WELL DECAYING  
CONVECTION FROM TODAY'S STORMS IN THE OHIO VALLEY WILL HOLD  
TOGETHER, MODEL GUIDANCE IS IN REASONABLY GOOD AGREEMENT THAT  
APPRECIABLE DAYTIME HEATING SHOULD ENSUE LATE TOMORROW MORNING  
INTO EARLY TOMORROW AFTERNOON. AS A RESULT, SURFACE BASED  
INSTABILITY WILL DEVELOP, AND STORMS ARE EXPECTED TO FORM BY  
EARLY- MID AFTERNOON ALONG A PRE-FRONTAL TROUGH. THERE IS STILL  
A BIT OF SPREAD REGARDING EXACTLY WHERE THIS PRE-FRONTAL TROUGH  
WILL SET UP, BUT MOST GUIDANCE HAS IT ORIENTED FROM SOUTHWEST  
TO NORTHEAST, SOMEWHERE ACROSS CENTRAL OR WESTERN PORTIONS OF  
THE FORECAST AREA. ENVIRONMENTALLY SPEAKING, MOST MODELS SHOW  
AROUND 500-1000 J/KG OF MLCAPE, WITHIN WHAT WILL BE A WELL  
SHEARED ENVIRONMENT (AROUND 40-50 KNOTS OF EFFECTIVE BULK  
SHEAR). INITIALLY, A MIXTURE OF SHORT LINE SEGMENTS AND  
SUPERCELLS MAY BE POSSIBLE, BEFORE UPSCALE GROWTH CAUSES  
ACTIVITY TO TURN PREDOMINANTLY LINEAR IN NATURE. THE PRIMARY  
HAZARD SHOULD BE DAMAGING WINDS, BUT A FEW INSTANCES OF LARGE  
HAIL OR A TORNADO CAN'T BE COMPLETELY RULED OUT. SPC CURRENTLY  
HAS THE BULK OF THE FORECAST AREA OUTLOOKED IN A SLIGHT RISK FOR  
SEVERE THUNDERSTORMS, WITH AN ENHANCED RISK CLIPPING CENTRAL  
VIRGINIA.  
 
STORMS SHOULD INITIALLY DEVELOP AROUND MID- AFTERNOON  
ACROSS CENTRAL AND WESTERN PORTIONS OF THE FORECAST AREA. STORM  
MOTIONS WILL BE OFF TOWARD THE NORTH AND EAST, BUT THE ZONE  
WHERE STORMS ARE DEVELOPING WILL GRADUALLY SHIFT TO THE SOUTH  
AND EAST, REACHING THE I-95 CORRIDOR DURING THE LATE AFTERNOON  
AND EVENING HOURS. STORMS WILL LINGER THROUGH THE EVENING ALONG  
AND SOUTHEAST OF I-95, BEFORE FINALLY CLEARING SOUTHERN MARYLAND  
AROUND OR JUST AFTER MIDNIGHT AS THE SYSTEM'S COLD FRONT MOVES  
THROUGH. NORTHWESTERLY WINDS, FALLING TEMPERATURES, AND DRY  
CONDITIONS ARE EXPECTED DURING THE SECOND HALF OF THE NIGHT.  
OVERNIGHT LOWS ARE FORECAST TO BE IN THE 40S FOR MOST, WITH 30S  
IN THE MOUNTAINS.  
 
SUNNY SKIES AND A NORTH TO NORTHWESTERLY BREEZE IS EXPECTED ON  
TUESDAY AS HIGH PRESSURE BUILDS TO OUR NORTH. HIGH TEMPERATURES  
ARE FORECAST TO REACH INTO THE UPPER 50S TO MID 60S FOR MOST,  
WITH UPPER 40S IN THE MOUNTAINS.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/
 
 
RIDGING WILL BUILD OVER THE EAST DURING THE MIDDLE AND SECOND HALF  
OF THE WEEK LEADING TO A WARMING TREND WITH 80S EXPECTED AGAIN.  
MOISTURE RETURN WILL BE UNDERWAY WED AFTERNOON INTO THU. LIGHT  
SHOWERS WILL BE POSSIBLE WED NIGHT INTO THU IN THE RETURN FLOW  
PARTICULARLY IN WESTERN AREAS, BUT ARE MORE LIKELY FRI INTO SAT WHEN  
CDFNT WILL BE MOVING SLOWLY ACROSS THE AREA AND AREA GETS INTO THE  
COOL SECTOR AND MULTIPLE WAVES OF LOW PRESSURE MOVE ALONG STALLED  
FRONTAL ZONE. AFTER TEMPS IN THE 80S THU AND FRI, EXPECT TEMPS TO  
COOL DOWN SIGNIFICANTLY FOR SAT AND SUN AND THE FOLLOWING WEEK.  
 

 
   
AVIATION /01Z MONDAY THROUGH FRIDAY/
 
 
SHOWERS OVER THE WV PANHANDLE AND WESTERN MD WILL CONTINUE TO  
PUSH OFF TO THE NORTHEAST AS THEY CONTINUE TO DECREASE IN  
COVERAGE. THE ONLY IMPACTED SITE WAS MRB, WITH SHOWERS FAILING  
TO REACH ANY TERMINALS EAST OF THE BLUE RIDGE. REMOVED  
PREVIOUSLY SENT PROB30S WITH THE AFTERNOON/EVENING TAFS FOR THIS  
EVENING.  
 
VFR CONDITIONS CONTINUE FOR MUCH OF TONIGHT. HOWEVER MVFR  
CEILINGS WILL BE POSSIBLE FOR A FEW HOURS LATE TONIGHT/EARLY  
TOMORROW MORNING AROUND SUNRISE, BEFORE CONDITIONS RETURN TO  
VFR TOMORROW MORNING. THERE'S A SLIGHT CHANCE FOR A SHOWER  
AROUND SUNRISE TOMORROW MORNING AS DECAYING ACTIVITY MOVES IN  
FROM THE WEST. WITH THE EVENING PACKAGE, HAVE INCLUDED SOME  
BRIEF PROB30S FOR THAT INTO THE 00Z TAFS.  
 
BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS WILL MOVE INTO THE  
AREA LATE TOMORROW AFTERNOON INTO TOMORROW EVENING AS A COLD  
FRONT APPROACHES FROM THE NORTHWEST. SOME OF THESE STORMS MAY BE  
STRONG TO SEVERE. THE 00Z TAF PACKAGE ATTEMPTS TO NAIL DOWN THE  
MOST CONFIDENT PERIOD OF THUNDERSTORMS. THERE COULD LEGITIMATELY  
BE A GOOD 3 TO 4 HOURS OF THUNDERSTORMS IN THAT 6 HOUR TIMEFRAME  
BETWEEN EARLY/MID AFTERNOON INTO TOMORROW EVENING. THERE ARE  
SOME QUESTIONS WITH HOW FAR EAST STORMS WILL POP UP, WITH MRB  
BEING THE LEAST CERTAIN TO ACTUALLY SEE THE WORST. SO, DID A  
PROB30 THERE RATHER THAN A TEMP, JUST TO DRIVE HOME THE FACT  
THAT THERE IS STILL A LOT OF UNCERTAINTY THERE. STORMS MAY JUST  
POP UP TOO FAR EAST, LEAVING MRB WITH PRIMARILY SHOWERS.  
 
THE WORST OF THE ACTIVITY WILL DEPART THE REGION BY LATE  
EVENING, WITH SHOWERS PERHAPS LINGERING INTO THE EARLY OVERNIGHT  
HOURS. OUTSIDE OF THUNDERSTORMS, WINDS WILL BE OUT OF THE SOUTH  
TOMORROW AROUND 20 TO 25 KNOTS. WITH SHOWERS AND STORMS  
DEPARTING, VFR CONDITIONS WILL RETURN DURING THE SECOND HALF OF  
THE NIGHT. WINDS WILL SHIFT TO OUT OF THE NORTHWEST BEHIND THE  
SYSTEM'S COLD FRONT DURING THE SECOND HALF OF THE NIGHT, PERHAPS  
GUSTING INTO THE 20 TO 25 KNOT RANGE ONCE AGAIN.  
 
VFR CONDITIONS AND NORTHWEST TO NORTHERLY FLOW ARE EXPECTED ON  
TUESDAY. GUSTY SW WINDS OF 25 TO 35 KT WILL BE POSSIBLE WED AND  
THU. LOTS OF CLOUDS BOTH DAYS, BUT NO CIG RESTRICTIONS ARE  
EXPECTED.  
 

 
   
MARINE
 
 
SCA CONDITIONS ARE LIKELY ON AND OFF THROUGH THE DAY TOMORROW  
WITHIN SOUTHERLY FLOW. THUNDERSTORMS APPEAR LIKELY TOMORROW  
AFTERNOON INTO TOMORROW EVENING, WITH SMWS LIKELY NEEDED DURING  
THAT TIME. SOME STORMS COULD CONTAIN WINDS IN EXCESS OF 50  
KNOTS, ESPECIALLY DURING THE LATE AFTERNOON THROUGHOUT THE  
ENTIRE EVENING. STORMS COULD EVEN LINGER OVER THE CENTRAL BAY  
AND LOWER POTOMAC THROUGH MIDNIGHT.  
 
WINDS TURN NORTHWESTERLY BEHIND A COLD FRONT DURING THE SECOND  
HALF OF TOMORROW NIGHT, AND REMAIN NORTH TO NORTHWESTERLY DURING  
THE DAY TUESDAY, WITH SCA LEVEL GUSTS LINGERING THROUGH TUESDAY  
MORNING.  
 
SCA CONDITIONS LIKELY WEDNESDAY THROUGH FRIDAY.  
 

 
   
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...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR MDZ008.  
VA...NONE.  
WV...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ530>543.  
 

 
 

 
 
SYNOPSIS...KJP  
NEAR TERM...CJL  
SHORT TERM...CJL/KJP  
LONG TERM...LFR  
AVIATION...LFR/CJL/KJP  
MARINE...LFR/CJL/KJP  
TIDES/COASTAL FLOODING...LWX  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab VA Page
The Nexlab MD Page
The Nexlab WV Page Main Text Page