896  
FXUS61 KLWX 140752  
AFDLWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC  
352 AM EDT FRI AUG 14 2020  
   
SYNOPSIS
 
 
A SURFACE FRONT WILL MEANDER OVER THE REGION THROUGH THE  
WEEKEND, BRINGING SHOWERS AND THUNDERSTORMS EACH DAY. LOW  
PRESSURE WILL DEVELOP ON THIS FRONT AND MOVE ACROSS THE REGION  
SATURDAY NIGHT INTO SUNDAY. HIGH PRESSURE WILL THEN BRIEFLY  
RETURN EARLY NEXT WEEK BEFORE AN UNSETTLED PATTERN LIKELY  
RETURNS BY THE MIDDLE OF THE WEEK.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
SEEING SEVERAL SHOWERS THAT HAVE DEVELOPED OVER CENTRAL VA AND  
ALONG THE CHESAPEAKE BAY. THIS IS ASSOCIATED WITH ONSHORE FLOW  
NORTH OF A DEEPENING SURFACE LOW ALONG THE NC COAST. THESE ARE  
PROGRESSIVE ENOUGH THAT FLOODING IS NOT A CONCERN AT THIS POINT  
WITH THIS SHOWER ACTIVITY.  
 
ELSEWHERE ACROSS THE AREA, MOSTLY CLOUDY SKIES HAVE PREVAILED,  
AND WILL CONTINUE TO DO SO THROUGH DAYBREAK. SOME PATCHY FOG  
SEEMS TO BE TRYING TO DEVELOP IN A FEW SPOTS, BUT VISIBILITIES  
AREN'T DROPPING ALL THAT MUCH. THINKING THE CLOUD COVER WILL  
KEEP FOG COVERAGE FAIRLY LOW AS WE HEAD INTO SUNRISE.  
 
FOR THE REST OF TODAY, A FRONTAL BOUNDARY TO OUR NORTH WILL DROP  
SOUTH THROUGH THE AREA TODAY. MEANWHILE, A SLOW MOVING UPPER LOW  
WILL BE APPROACHING FROM THE WEST. THIS WILL LEAD TO MORE  
SHOWERS AND STORMS TODAY, ESPECIALLY INTO THE AFTERNOON HOURS.  
HI-RES GUIDANCE DOESN'T PAINT AN OMINOUS PICTURE TODAY, WITH QPF  
AMOUNTS MUCH LIGHTER THAN IN PREVIOUS DAYS ON THE 00Z HREF.  
ADDITIONALLY, ANY SHOWERS/STORMS SHOULD BE RELATIVELY  
PROGRESSIVE (AS WE ARE SEEING THIS MORNING). OF COURSE, GIVEN  
THE ANTECEDENT CONDITIONS ACROSS A MAJORITY OF THE AREA, WILL  
HAVE TO WATCH FOR ANY HEAVIER ELEMENTS THAT MAY TRY TO TRAIN  
ALONG THE FRONT ITSELF. HOWEVER, WITH THE FRONT ACTUALLY MOVING  
TODAY, THINK THIS WILL BE HARDER TO DO.  
 
A BRIEF LULL IN ACTIVITY IS POSSIBLE OVERNIGHT TONIGHT FOR MUCH  
OF THE AREA, THOUGH DO EXPECT LINGERING SHOWERS OVERNIGHT IN  
CENTRAL VA AND EASTERN WV. OVERNIGHT LOWS INTO THE UPPER 60S/LOW  
70S (UPPER 50S TO LOW 60S IN THE HIGHER ELEVATIONS).  
 

 
   
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
 
 
ON SATURDAY, THE SLOW-MOVING UPPER TROUGH OVER THE OHIO VALLEY  
WILL FINALLY SWING THROUGH THE REGION. ADDITIONALLY, AT THE  
SURFACE, THE AFOREMENTIONED FRONTAL BOUNDARY WILL REMAIN OVER  
CENTRAL VA. MEANWHILE, A SURFACE LOW WILL DEVELOP EAST OF THE  
UPPER TROUGH AND LATCH ONTO THIS FRONT. THIS WILL RESULT IN LOW  
PRESSURE MOVING JUST TO THE SOUTH OF THE REGION LATER SATURDAY  
INTO EARLY SUNDAY. THE TRACK MAY MOVE RIGHT OVER SOME OF OUR  
SOUTHERN ZONES. ONSHORE FLOW ASSOCIATED WITH THIS SYSTEM COULD  
LEAD TO LOCALLY ENHANCED RAINFALL ALONG THE RIDGES AND IN THE  
POTOMAC HIGHLANDS. GUIDANCE THEN TAKES THE LOW ACROSS SOUTHERN  
MD INTO THE DELMARVA OVERNIGHT, WHILE ALSO GRADUALLY  
STRENGTHENING IT. RAINFALL AMOUNTS COULD ALSO BE LOCALLY BE  
ENHANCED FROM CENTRAL VIRGINIA TO SOUTHERN MARYLAND, WHERE  
THEY'LL STAND THE BEST CHANCE OF DESTABILIZING AND DEVELOPING  
SOME CONVECTIVE ELEMENTS. WITH THE CONTINUED CLOUDS AND STORMS,  
HIGHS WILL CONTINUE TO BE IN THE 80S. LOWS WILL BE IN THE 60S  
TO 70S.  
 
ALL THIS BEING SAID, LOOKING AT A POTENTIAL FOR FLOODING  
SATURDAY/SATURDAY NIGHT. CURRENT FORECAST SHOWS 2-3 INCHES OF  
RAIN WITH THIS SYSTEM ACROSS CENTRAL VA AND INTO SOUTHERN MD.  
SOME LOCALLY HIGHER AMOUNTS ARE LIKELY WITH CONVECTIVE ELEMENTS  
AND UPSLOPE FLOW. GIVEN THE RECENT HEAVY RAINS, IT ISN'T GOING  
TO TAKE MUCH TO CAUSE MORE FLOODING ISSUES.  
 
BY SUNDAY MORNING, THE LOW SHOULD BE PUSHING OFF TO THE EAST,  
TAKING THE RAIN WITH IT. SOME GUIDANCE IS A LITTLE SLOWER  
HOWEVER, SO LEAVING SOME POPS IN THROUGH THE EARLY AFTERNOON.  
THOUGH, DO THINK THERE IS A GOOD SHOT WE ARE DRY BY EARLY  
AFTERNOON. SUNDAY WILL BE MUCH COOLER THAN NORMAL, WITH HIGHS IN  
THE MID TO UPPER 70S (LOW 80S CLOSER TO THE WATER). JUST HOPE WE  
CAN GET THE RAIN OUT OF HERE EARLY ENOUGH TO ENJOY IT. SUNDAY  
NIGHT WILL BE DRY, WITH LOWS RANGING FROM THE MID 50S IN THE  
HIGHER ELEVATIONS TO UPPER 60S IN THE TYPICAL NORMAL AREAS ALONG  
THE WATERS.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
TROUGHINESS WILL DOMINATE THE EAST COAST STATES THE FIRST HALF OF  
NEXT WEEK KEEPING TEMPS AOB NORMAL. THERE WILL BE DRYING FOR THE  
FIRST PART OF THE WEEK AS NW FLOW DEVELOPS IN THE WAKE OF LOW  
PRESSURE ORGANIZING OFFSHORE. BY THE MIDDLE OF THE WEEK, MOISTURE  
BEGINS TO INCREASE AS SFC HIGH MOVES OFFSHORE AND SRLY FLOW  
DEVELOPS. HOWEVER, MOISTURE SUPPLY IS NOT EXPECTED TO BE ANYWHERE  
CLOSE TO THE PAST FEW DAYS, SO THE RISK OF EXCESSIVE RAINFALL  
APPEARS LOW AT THIS TIME. RIDGING TRIES TO BUILD ALONG THE EAST  
COAST FOR THE SECOND HALF OF NEXT WEEK LIKELY LIMITING AREAL  
COVERAGE OF SHOWERS AND T-STORMS.  
 

 
   
AVIATION /07Z FRIDAY THROUGH TUESDAY/
 
 
CURRENTLY SEEING PLENTY OF LOWER CLOUDS THIS MORNING THANKS TO  
PLENTIFUL LOW-LEVEL MOISTURE FLOWING INTO THE AREA IN ONSHORE  
FLOW. FOG WILL STRUGGLE TO FORM THIS MORNING THOUGH, WITH VERY  
LITTLE IN TERMS OF CLEARING AND WINDS OF 5-10 KTS. IFR  
CONDITIONS WILL PERSIST THROUGH 13Z OR SO FOR MOST TERMINALS  
DUE TO LOW CIGS. CLOUDS WILL GRADUALLY LIFT THROUGH THE DAY, BUT  
LIKELY REMAIN MVFR MUCH OF THE DAY. SHOWERS AND STORMS POSSIBLE  
AGAIN TODAY, BUT CONFIDENCE TOO LOW IN EXACT PLACEMENT TO ADD  
INTO TAFS AT THIS TIME. DO THINK THE BEST SHOT WILL BE FOR  
CHO/MRB THOUGH.  
 
MORE SIGNIFICANT CHANCE FOR RAINFALL WILL MOVE INTO THE REGION  
SATURDAY AFTERNOON AND CONTINUE THROUGH EARLY SUNDAY, AS LOW  
PRESSURE TRACKS ALONG A STATIONARY FRONT TO OUR SOUTH. LOCALLY  
HEAVY RAIN IS POSSIBLE WITH THIS SYSTEM, AND POTENTIALLY SOME  
EMBEDDED THUNDERSTORMS (PRIMARILY TOWARDS CHO). VSBY/CIG  
RESTRICTIONS LIKELY DURING THIS TIME.  
 
CONDITIONS BEGIN TO CLEAR LATER IN THE DAY ON SUNDAY, AS LOW  
PRESSURE PUSHES OFF TO THE EAST, WITH HIGH PRESSURE BUILDING IN  
BEHIND IT AND VFR CONDITIONS RETURNING.  
 
NO SIG WX EXPECTED THE FIRST HALF OF NEXT WEEK.  
 

 
   
MARINE
 
 
GENERALLY SUB-SCA CONDITIONS EXPECTED ON THE WATERS THROUGH  
SATURDAY. MAIN CONCERN EACH DAY WILL BE THUNDERSTORMS, PRIMARILY  
DURING THE AFTERNOON HOURS, THOUGH SOME MAY DEVELOP DURING THE  
MORNINGS. GUSTY WINDS AND EVEN A FEW WATERSPOUTS WILL BE  
POSSIBLE WITH STRONGER STORMS.  
 
ONSHORE FLOW IS EXPECTED TO PERSIST SUNDAY, AND MAY BE NEAR SMALL  
CRAFT ADVISORY (SCA) LEVELS.  
 
SCA CONDITIONS POSSIBLE MONDAY MORNING. OTHERWISE, WINDS SHOULD  
DIMINISH THROUGH TIME NEXT WEEK.  
 

 
   
TIDES/COASTAL FLOODING
 
 
MINOR COASTAL FLOODING IS POSSIBLE LATE SAT NIGHT AND SUN AS ONSHORE  
FLOW STRENGTHENS AS LOW PRESSURE PASSES TO THE SOUTH.  
 

 
   
LWX WATCHES/WARNINGS/ADVISORIES
 
 
DC...NONE.  
MD...NONE.  
VA...NONE.  
WV...NONE.  
MARINE...NONE.  
 

 
 

 
SYNOPSIS...CJL  
NEAR TERM...CJL  
SHORT TERM...CJL/KJP  
LONG TERM...LFR  
AVIATION...LFR/CJL  
MARINE...LFR/CJL  
TIDES/COASTAL FLOODING...LFR  
 
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