717  
FXUS61 KLWX 271916  
AFDLWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC  
316 PM EDT SUN APR 27 2025  
   
SYNOPSIS
 
 
CANADIAN HIGH PRESSURE WILL BUILD INTO THE AREA THROUGH MONDAY  
BEFORE MOVING OFFSHORE. A WARM FRONT MOVES THROUGH TUESDAY WHILE  
ANOTHER FRONT WILL WAVER ACROSS THE MID-ATLANTIC WEDNESDAY AND  
THURSDAY. A COLD FRONT SWEEPS THROUGH ON FRIDAY WITH HIGH  
PRESSURE RETURNING FOR NEXT WEEKEND.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
THE GRADIENT BETWEEN LOW PRESSURE IN THE CANADIAN MARITIMES AND  
HIGH PRESSURE NEAR DETROIT CONTINUES TO RESULT IN GUSTY WINDS  
THIS AFTERNOON. THESE WINDS SHOULD WANE RATHER QUICKLY WITH  
SUNSET. CLEAR AND CALM CONDITIONS ARE EXPECTED THE SECOND HALF  
OF THE NIGHT AS THE HIGH SETTLES OVERHEAD, RESULTING IN  
FAVORABLE RADIATIONAL COOLING CONDITIONS. GIVEN DEW POINTS IN  
THE UPPER 20S AND LOWER 30S, SHELTERED VALLEYS MAY GET RATHER  
COLD. IT'S POSSIBLE THAT IT WILL BE TOO DRY FOR FROST  
FORMATION, BUT WITH TEMPERATURES DROPPING TO NEAR FREEZING,  
THOUGHT IT WAS PRUDENT TO HAVE A FROST ADVISORY FOR THE CENTRAL  
SHENANDOAH VALLEY (THE GROWING SEASON HASN'T STARTED FOR  
LOCATIONS TO THE WEST). ELSEWHERE, LOWS WILL BE IN THE UPPER 30S  
AND 40S, REMAINING NEAR 50 IN THE URBAN CENTERS AND BAYSHORE.  
 

 
   
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/
 
 
THE HIGH WILL BEGIN TO SLIDE TO THE EAST MONDAY WHILE UPPER  
RIDGING BUILDS FROM THE WEST. THIS WILL RESULT IN A WARMING  
TREND, ALTHOUGH WINDS WILL REMAIN LIGHT. HIGHS WILL BE IN THE  
70S WITH LOWS IN THE MID 40S TO MID 50S.  
 
RIDGING WILL CONTINUE TO DOMINATE INTO TUESDAY, WITH THE WARM  
ADVECTION PATTERN BOOSTING TEMPERATURES WELL ABOVE NORMAL. MOST  
LOCATIONS WILL REACH THE 80S. LOW PRESSURE LIFTING NORTHEAST OF  
THE GREAT LAKES WILL SEND A COLD FRONT TOWARD THE OHIO VALLEY.  
SHOWERS AND THUNDERSTORMS WILL DEVELOP AHEAD OF THIS BOUNDARY.  
LOCALLY, THERE IS SOME QUESTION HOW LONG THE ATMOSPHERE WILL  
REMAIN CAPPED. EARLIER INITIATION COULD RESULT IN SOME ATTENDANT  
SEVERE WEATHER RISK IN THE NORTHWESTERN CORNER OF THE CWA GIVEN  
SUFFICIENT INSTABILITY AND SHEAR PRESENT. HOWEVER, IT'S POSSIBLE  
CONVECTION REMAINS FARTHER UPSTREAM ALONG THE FRONTAL ZONE, WITH  
ONLY SOME REMNANTS REACHING THE AREA DURING THE EVENING OR  
OVERNIGHT...WHICH WOULD CARRY A LOWER SEVERE RISK. IT DOES  
APPEAR THAT ACTIVITY WILL STRUGGLE TO HOLD TOGETHER EAST OF THE  
MOUNTAINS OVERNIGHT. THE COLD FRONT WILL LIKELY ENTER THE AREA  
TOWARD WEDNESDAY MORNING. THE CLOUDS AND HIGHER DEW POINTS WILL  
RESULT IN LOWS ONLY FALLING INTO THE 60S.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/
 
 
A WARM AND ACTIVE MIDDLE TO LATE PART OF THE WEEK WITH SHOWERS AND  
THUNDERSTORMS IN THE FORECAST EACH DAY. DRY AND COOLER NEXT WEEKEND.  
 
THE COLD FRONT MOVES INTO THE AREA EARLY WEDNESDAY MORNING, AND  
SLOWLY SAGS SOUTH THROUGH THE AFTERNOON TO EVENING. THE POSITION OF  
THE FRONT IS GOING TO PLAY A KEY ROLE IN WHERE MORE ROBUST  
THUNDERSTORMS CAN DEVELOP IN THE AFTERNOON TO EVENING. SOUTH OF THE  
BOUNDARY TEMPERATURES SHOULD RISE TO THE LOW TO MID 80S, WITH DEW  
POINTS IN THE LOW 60S. WEAK DEEP LAYER SHEAR (30-35 KNOTS) AND  
MODEST INSTABILITY WILL LIKELY SUPPORT SOME ORGANIZED THUNDERSTORM  
ACTIVITY. IT REMAINS TO BE SEEN WHETHER ANY STORMS BECOME STRONG TO  
SEVERE, THOUGH THE BEST CHANCE FOR THAT WILL BE SOUTH OF I-66.  
 
THE FRONT LIKELY DOES NOT COMPLETELY CLEAR THE AREA, INSTEAD BEGINS  
TO LIFT NORTH AS A WARM FRONT ON THURSDAY WITH SOUTHERLY WINDS  
RETURNING. A PROGRESSIVE UPPER TROUGH QUICKLY MOVES DISTURBANCE  
ALOFT MOVES FROM THE MID-SOUTH/OH VALLEY THROUGH THE MID-ATLANTIC  
THURSDAY AFTERNOON INTO THURSDAY NIGHT. EXPECT ANOTHER ROUND OF  
SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON/EVENING THAT WILL  
LIKELY BE OF GREATER COVERAGE THAN WEDNESDAY. ANOTHER UPPER TROUGH  
AND ASSOCIATED COLD FRONT QUICKLY MOVE IN FROM THE WEST ON FRIDAY,  
BRINGING YET ANOTHER ROUND OF ROUND OF SHOWERS AND THUNDERSTORMS.  
 
DRY AND COOLER CONDITIONS NEXT WEEKEND AS HIGH PRESSURE BUILDS ATOP  
THE REGION. TEMPERATURES MOSTLY IN THE 60S TO 70S, WITH OVERNIGHT  
LOWS IN THE 40S TO LOW 50S.  
 

 
   
AVIATION /19Z SUNDAY THROUGH FRIDAY/
 
 
VFR CONDITIONS ARE EXPECTED THROUGH TUESDAY. NW WINDS GUSTING TO  
30 KT WILL SUBSIDE FAIRLY QUICKLY THIS EVENING AS HIGH PRESSURE  
BUILDS OVERHEAD. LIGHT SOUTH WINDS DEVELOP MONDAY AFTER THE HIGH  
MOVES TO THE EAST. GUSTS COULD INCREASE TO AROUND 20 KT TUESDAY  
AFTERNOON.  
 
THERE IS A LOW CHANCE THAT SOME SHOWERS AND THUNDERSTORMS REACH  
THE AREA LATE TUESDAY NIGHT. SOME LOWER CLOUDS MAY ALSO  
ACCOMPANY A DESCENDING COLD FRONT. THE GREATEST POTENTIAL FOR  
BOTH PHENOMENA WOULD BE AT MRB.  
 
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE END OF THE WEEK.  
HOWEVER, THERE WILL BE SHOWER AND THUNDERSTORM CHANCES EACH DAY  
DURING THE AFTERNOON TO EVENING HOURS. ANY STORM THAT MOVES OVER A  
TERMINAL COULD RESULT IN BRIEF SUB-VFR CONDITIONS AND GUSTY  
WINDS.  
 

 
   
MARINE
 
 
HIGH END SMALL CRAFT ADVISORY CONDITIONS (NORTHWESTERLY GUSTS  
TO 30 KT) WILL CONTINUE THROUGH THE AFTERNOON AS LOW PRESSURE  
DEPARTS MAINE. SOME OCCASIONAL GUSTS EXCEEDING 30 KT CONTINUE  
ACROSS THE NORTHERN BAY AND UPPER TIDAL POTOMAC.  
 
WHILE NARROWER/SHELTERED WATERS SHOULD HAVE WINDS SUBSIDE  
QUICKLY THIS EVENING AS HIGH PRESSURE BUILDS CLOSER, A NORTHERLY  
LOW LEVEL WIND OF AROUND 25 KT WILL REMAIN ALIGNED ALONG THE  
CHESAPEAKE BAY. WITH AIR TEMPERATURES FALLING BELOW WATER  
TEMPERATURES, FAVORABLE MIXING AND CHANNELING SHOULD BRING SOME  
OF THESE HIGHER WINDS TO THE SURFACE. ADVISORIES CONTINUE FOR  
THIS AREA INTO THE NIGHT.  
 
CANADIAN HIGH PRESSURE SHOULD KEEP WINDS ON THE LIGHTER SIDE  
MONDAY. AS THIS RIDGE RETREATS OFFSHORE, WINDS RETURN TO  
SOUTHERLY BY MONDAY EVENING. SOME CHANNELING EFFECTS MAY OCCUR  
MONDAY NIGHT, WHICH MAY WARRANT ADDITIONAL SMALL CRAFT  
ADVISORIES FOR PORTIONS OF THE WATERS. A GREATER CHANCE FOR  
ADVISORY CONDITIONS ON ALL WATERS WILL OCCUR ON TUESDAY.  
 
OVERALL WINDS ARE FORECAST TO REMAIN BELOW SCA LEVELS WEDNESDAY  
THROUGH THURSDAY EVENING. A COLD FRONT MOVES SOUTH THROUGH THE  
AREA ON WEDNESDAY, THEN LIFTS BACK NORTH AS WARM FRONT ON  
THURSDAY. ANY IMPACT TO MARINERS LOOKS TO BE FROM DAILY CHANCES  
FOR THUNDERSTORMS, ESPECIALLY THURSDAY AND FRIDAY. MOST OF THESE  
STORMS WILL OCCUR DURING THE AFTERNOON TO EVENING HOURS.  
 

 
   
LWX WATCHES/WARNINGS/ADVISORIES
 
 
DC...NONE.  
MD...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MDZ008.  
VA...FROST ADVISORY FROM 2 AM TO 8 AM EDT MONDAY FOR VAZ025>027-029.  
WV...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ530>532-  
539>541.  
SMALL CRAFT ADVISORY UNTIL 3 AM EDT MONDAY FOR ANZ533-534-537-  
543.  
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ535-  
536-538-542.  
 

 
 

 
 
SYNOPSIS...ADS  
NEAR TERM...ADS  
SHORT TERM...ADS  
LONG TERM...KRR  
AVIATION...ADS/KRR  
MARINE...ADS/KRR  
 
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