311  
FXUS61 KLWX 150851  
AFDLWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC  
351 AM EST FRI NOV 15 2024  
   
SYNOPSIS
 
 
LOW PRESSURE AND IT'S ASSOCIATED COLD FRONT WILL SLOWLY PUSH  
OFFSHORE LATER THIS MORNING ALLOWING PRECIPITATION CHANCES TO  
SUBSIDE OUTSIDE THE MOUNTAINS. HIGH PRESSURE BUILDS THIS WEEKEND  
BRINGING MODERATING TEMPERATURES AND DRY CONDITIONS. PRECIPITATION  
CHANCES RETURN WITH A STRONG COLD FRONT AND AREA OF LOW PRESSURE  
DURING THE MIDDLE AND LATTER HALF OF NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
CLOSED UPPER LEVEL LOW PRESSURE WILL CONTINUE OFFSHORE THIS MORNING  
WHILE SURFACE LOW PRESSURE SITS OFF THE COAST OF NORTH CAROLINA. AS  
A RESULT, EXPECT LINGERING SHOWER CHANCES ALONG AND EAST OF I-95 AS  
WELL AS BACK ACROSS THE ALLEGHENIES WHERE RESIDUAL SHORTWAVE  
TROUGHING RESIDES. SHOWER CHANCES WILL CONTINUE ALONG THE ALLEGHENY  
FRONT THROUGH EARLY SATURDAY AS A RESULT OF THIS SHORTWAVE TROUGH  
SLOWLY PIVOTING THROUGH. 00Z AND 06Z HAS TRENDED SLOWER WHEN IT  
COMES TO BOTH DECREASING CLOUDS AND LIGHT PRECIPITATION CHANCES THIS  
MORNING. WITH THAT SAID, HAVE HELD ONTO BOTH A BIT LONGER MAINLY  
EAST OF THE BLUE RIDGE AND WEST OF THE ALLEGHENIES WITH THE DRY SLOT  
WINNING OUT IN BETWEEN MID TO LATE AFTERNOON. OF COURSE ALL OF THIS  
WILL DEPEND ON HOW QUICKLY THE PARENT LOW PRESSURE SYSTEM EXITS THE  
AREA THIS MORNING.  
 
SKIES WILL SLOWLY CLEAR THIS AFTERNOON AND EVENING WITH A MIX OF SUN  
AND CLOUDS EXPECTED. THIS IS DUE IN PART TO BUILDING HIGH PRESSURE  
THAT WILL CONTROL THE WEATHER FOR THE START OF THE UPCOMING WEEKEND  
AHEAD. HIGH TEMPERATURES TODAY IN THE MID/UPPER 50S (40S TO LOW 50S  
FOR MOUNTAIN LOCATIONS). LOWS TONIGHT WILL FALL INTO THE UPPER 30S  
AND LOWER 40S.  
 

 
   
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
 
 
DRY AND SEASONABLE CONDITIONS ARE EXPECTED THROUGHOUT THE WEEKEND  
WITH HIGHS IN THE UPPER 50S AND LOW 60S. MOUNTAIN LOCATIONS WILL BE  
TOUCH COOLER WITH UPPER 40S AND LOW 50S SATURDAY, WARMING INTO THE  
MID 50S SUNDAY. LOWS SATURDAY NIGHT WILL FALL BACK INTO THE MID TO  
UPPER 30S. SHELTERED VALLEY LOCATIONS WILL RADIATE OUT INTO THE  
UPPER 20S AND LOW 30S. SUNDAY NIGHT LOWS WILL MODERATE INTO THE  
UPPER 309S AND LOW TO MID 40S.  
 
THE ONLY HAZARD WITHIN THE SHORT TERM PERIOD IS FIRE WEATHER FOR  
CENTRAL AND NORTHEAST PORTIONS OF MARYLAND. THIS IS LARGELY DUE IN  
PART TO A LACK OF RAINFALL IN THESE LOCATIONS (I.E AMOUNTS LESS THAN  
0.10" OVER THE PAST 24 TO 36 HOURS). THE LACK OF RAINFALL, PROLONGED  
DROUGHT, AND INCREASED WINDS SATURDAY (GUSTS UP TO 20 KTS) WILL LEAD  
TO ELEVATED FIRE CONCERNS.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
STRONG UPPER LEVEL RIDGING WILL CONTINUE TO DOMINATE THROUGH AT  
LEAST WEDNESDAY WITH A BIG PATTERN CHANGE LATE NEXT WEEK. A WEAK  
SHORTWAVE TROUGH PASSING TO THE NORTH WILL DROP A WEAK COLD FRONT  
INTO THE AREA MONDAY. A SHOWER OR SPRINKLE IS POSSIBLE WITH THIS  
FRONT WEST OF THE ALLEGHENY FRONT. HIGH TEMPERATURES MONDAY WILL  
PUSH INTO THE MID TO UPPER 60S AND LOW 70S EAST OF THE MOUNTAINS.  
LOWS MONDAY NIGHT WILL FALL INTO THE UPPER 30S AND LOW 40S.  
 
THE WEATHER PATTERN BEGINS TO TRANSITION A BIT TUESDAY INTO  
WEDNESDAY. SYNOPTICALLY, WE REMAIN SANDWICHED BETWEEN CUTOFF LOW  
PRESSURE OVER THE NORTHWEST ATLANTIC AND MID-MISSISSIPPI RIVER  
VALLEY. A FLATTENING RIDGE AND DIFFUSE FRONTAL ZONE REMAINS IN  
BETWEEN THE TWO LOW PRESSURE SYSTEMS TRANSLATING TO INCREASED CLOUD  
COVER AND MOUNTAIN RAIN SHOWERS. HIGHS TUESDAY WILL BE SLIGHTLY  
COOLER IN THE UPPER 50S AND LOW TO MID 60S UNDER ADDED CLOUD COVER.  
 
BIGGER CHANGES TO THE WEATHER PATTERN ARRIVE WEDNESDAY INTO THE  
LATTER HALF OF THE WORKWEEK. UPPER LEVEL LOW PRESSURE OVER THE MID-  
MS RIVER VALLEY WILL EJECT EASTWARD INTO THE OHIO RIVER VALLEY. A  
STRONG COLD FRONT WILL ACCOMPANY THIS SYSTEM SOMETIME THURSDAY INTO  
FRIDAY. 00/06Z GUIDANCE IS IN SOMEWHAT BETTER AGREEMENT ON THE  
TIMING OF THE FRONT, BUT UNCERTAINTY REMAINS GIVEN SUBTLE  
DIFFERENCES AMONGST THE PLACEMENT OF THE DEEP DIGGING TROUGH WITHIN  
BOTH THE DETERMINISTIC/ENSEMBLE GUIDANCE. NO SIGNIFICANT WEATHER  
IMPACTS ARE EXPECTED OVER THE NEXT 7 DAYS, BUT WILL CONTINUE TO  
MONITOR GIVEN THE UPCOMING HOLIDAY TRAVEL PERIOD.  
 
WHAT WE DO KNOW IS THAT A DEFINITIVE COOL-DOWN IS ON THE WAY  
FOR THE THANKSGIVING HOLIDAY. THIS CONTINUES TO BE HIGHLIGHTED  
IN THE 8-14 DAY TEMPERATURE TRENDS FROM THE CLIMATE PREDICTION  
CENTER. MODERATE WINDS AND SNOW THREATS ARE ALSO HIGHLIGHTED FOR  
THIS SAME PERIOD ARE THE APPALACHIANS REGION.  
 

 
   
AVIATION /09Z FRIDAY THROUGH TUESDAY/
 
 
MVFR TO PATCHY IFR VSBYS AND IFR TO LIFR CIGS WILL CONTINUE THIS  
MORNING AS LOW PRESSURE SLOWLY EXITS THE AREA. RESIDUAL LIGHT TO  
MODERATE SHOWER/DRIZZLE ACTIVITY WILL LINGER AT TERMINALS EAST OF A  
LINE FROM KMRB DOWN TO KCHO THROUGH AT LEAST 13-15Z/8AM-10AM. BEYOND  
THIS POINT, DRIER AIR WILL TAKE OVER WITH MVFR CONDITIONS EXPECTED  
LATER THIS MORNING AND VFR CONDITIONS RETURNING TO ALL TERMINALS  
LATER THIS AFTERNOON. WINDS WILL REMAIN OUT OF THE E/NE THIS MORNING  
A 5-10 KTS WITH A FEW GUSTS UP TO 18 KTS AT TERMINALS CLOSEST TO THE  
WATERS (I.E KBWI/KDCA). WINDS WILL TURN TO THE NORTHWEST THIS  
AFTERNOON WITH GUSTS RUNNING BETWEEN 15 TO 20 KTS.  
 
VFR CONDITIONS CONTINUE THROUGH SATURDAY NIGHT. WIND WILL BE THE  
ONLY IMPACT TO AVIATION THIS WEEKEND WITH NORTHWESTERLY GUSTS  
RUNNING 15 TO 25 KTS. WINDS WILL SLACKEN WHILE SWITCHING TO THE  
SOUTHWEST SUNDAY. VFR CONDITIONS WILL CONTINUE DURING THIS TIME WITH  
ADDED MID AND HIGH LEVEL CLOUD COVER.  
 
NO SIGNIFICANT WEATHER IS MONDAY OR TUESDAY OUTSIDE OF A FEW  
MOUNTAIN SHOWERS WEST OF KMRB. WINDS WILL TURN BACK TO THE  
WEST/NORTHWEST WITH GUSTS UP TO 15 KTS MONDAY. NEXT CHANCE OF SUB-  
VFR CONDITIONS ARRIVE WITH ANOTHER STRONG COLD FRONT AND LOW  
PRESSURE SYSTEM BY THE MIDDLE AND END OF NEXT WEEK.  
 

 
   
MARINE
 
 
SCA CONDITIONS LOOK TO CONTINUE ACROSS ALL WATERS  
THROUGH SATURDAY MORNING. EAST TO NORTHEAST WINDS THIS MORNING  
WILL SWITCH TO THE NORTHWEST THIS AFTERNOON INTO SATURDAY. GUSTS  
OF 15 TO25 KTS ARE EXPECT THROUGH THIS EVENING. WINDS WILL  
INCREASE TONIGHT INTO SATURDAY AS THE GRADIENT TIGHTENS BETWEEN  
DEPARTING LOW PRESSURE OFFSHORE AND INCOMING HIGH PRESSURE FROM  
THE OHIO RIVER VALLEY. GUSTS OF 20 TO 30 KTS ARE POSSIBLE  
SATURDAY ESPECIALLY OVER THE OPEN WATERS. WINDS WILL SLOWLY  
DIMINISH LATE SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE BUILDS  
OVERHEAD.  
 
SUB-SCA LEVEL WINDS RETURN LATE SUNDAY MORNING INTO MONDAY WITH HIGH  
PRESSURE OVERHEAD. WINDS WILL SWITCH BACK TO THE SOUTHWEST SUNDAY  
BEFORE TURNING TO THE WEST AND NORTHWEST MONDAY WITH GUSTS LESS THAN  
15KTS. A WEAK UPPER-LEVEL DISTURBANCE SWINGING THROUGH MONDAY NIGHT  
INTO TUESDAY COULD BRIEFLY KICK WINDS BACK UP OUT OF THE NW, WHICH  
COULD NEAR SCA CRITERIA. ADDITIONAL SCA CONDITIONS ARE POSSIBLE MID  
TO LATE NEXT WEEK AS A STRONG FRONT AND LOW PRESSURE CROSS THE  
REGION.  
 

 
   
FIRE WEATHER
 
 
DECREASED FIRE WEATHER CONDITIONS TODAY DUE TO RECENT PRECIPITATION  
AND ADDED CLOUD COVER. RAINFALL AMOUNTS RANGE FROM A FEW ONE  
HUNDREDTHS ACROSS NORTHEAST MD TO UPWARDS OF AN INCH ACROSS THE  
CENTRAL/SOUTHERN SHENANDOAH VALLEY.  
 
DRIER AIR RETURNS WITH HIGH PRESSURE AND GUSTY NORTH TO NORTHWEST  
FLOW FOR THE START OF THE WEEKEND. WIND GUSTS UP TO 20 KTS ARE  
POSSIBLE SATURDAY WITH MINIMUM RH VALUES FALLING BACK INTO THE 40 TO  
50 PERCENT RANGE. SIMILAR MINIMUM RH CONDITIONS (35 TO 45 PERCENT)  
ARE EXPECTED SUNDAY WITH WIND GUSTS LESS THAN 15 KTS.  
 
HIGHEST POTENTIAL FOR ELEVATED FIRE WEATHER CONDITIONS THIS WEEKEND  
INTO EARLY NEXT WEEK WOULD BE ACROSS NORTHEAST MD AND THE MD/PA LINE  
WHERE RAINFALL TOTALS WERE LESS THAN A TENTH OF AN INCH OVER THE  
PAST 36 HOURS. THE ADDED DROUGHT IN THESE LOCATIONS WILL FURTHER  
THIS CONCERN.  
 

 
   
TIDES/COASTAL FLOODING
 
 
TIDAL ANOMALIES WILL REMAIN ELEVATED DUE TO ONSHORE FLOW THROUGH  
THIS MORNING, BEFORE OFFSHORE FLOW LOWERS ANOMALIES TONIGHT. MINOR  
FLOODING IS ANTICIPATED AT ANNAPOLIS AND WASHINGTON DC SW WATERFRONT  
THROUGH THIS AFTERNOON, WITH NEAR MINOR POSSIBLE AT SEVERAL OTHER  
SITES UNTIL WATER LEVELS RECEDE.  
 

 
   
LWX WATCHES/WARNINGS/ADVISORIES
 
 
DC...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR DCZ001.  
MD...SMALL CRAFT ADVISORY UNTIL 6 PM EST SATURDAY FOR MDZ008.  
COASTAL FLOOD ADVISORY UNTIL 10 PM EST THIS EVENING FOR MDZ014.  
COASTAL FLOOD ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR  
MDZ016-018.  
VA...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ054.  
COASTAL FLOOD ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR  
VAZ057.  
WV...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST SATURDAY FOR ANZ530>534-  
536>543.  
SMALL CRAFT ADVISORY FROM 7 AM TO 6 PM EST SATURDAY FOR ANZ535.  
 

 
 

 
 
SYNOPSIS...EST  
NEAR TERM...LFR  
SHORT TERM...LFR/EST  
LONG TERM...LFR/EST  
AVIATION...LFR/EST  
MARINE...LFR/EST  
FIRE WEATHER...EST  
TIDES/COASTAL FLOODING...LFR/DHOF  
 
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