216  
FXUS61 KCTP 150148  
AFDCTP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE STATE COLLEGE PA  
948 PM EDT FRI AUG 14 2020  
   
SYNOPSIS
 
 
A STATIONARY FRONT WILL REMAIN DRAPED ALONG AND SOUTH OF THE  
MARYLAND BORDER FOR THE NEXT FEW DAYS. A WAVE OF LOW PRESSURE  
WILL RIDE ALONG THIS BOUNDARY OVER THE WEEKEND, PASSING JUST  
SOUTH OF THE STATE. A COLD FRONT IS THEN LIKELY TO PUSH ACROSS  
THE REGION ON MONDAY.  
 

 
   
NEAR TERM /UNTIL 8 AM SATURDAY MORNING/
 
 
ALL IS LOOKING GOOD. HIGH CLOUDS WILL PROBABLY CONTINUE TO  
STREAM OVER THE AREA OVERNIGHT, AND SOME LOW CLOUDS OUT THERE,  
TOO, SHOULD HELP PREVENT FOG FORMATION IN MOST PLACES. LITTLE  
CHANGE TO WHAT IS GOING.  
 
PREV...  
RADAR ALMOST ENTIRELY QUIET, EXCEPT FOR A FEW PINPOINTS OVER  
SRN SOMERSET AND CENTRAL YORK COS. ANY ADDITIONAL DEVELOPMENT  
WILL BE SPARSE AND WEAK, AND NOTHING SHOULD BE PRODUCING RAIN  
PAST 10PM. HAVE CONTINUED THE TREND OF REDUCING POPS. TEMPS  
RUNNING A LITTLE WARMER THAN SCHEDULED, AND THE HIGH CLOUD COVER  
MAY HELP TO KEEP THEM A LITTLE MILDER ON THE WHOLE THRU THE  
NIGHT. SOME PATCHY FOG IS POSSIBLE IN THE NORTH, BUT LOTS OF  
BENIGN CLOUD COVER - AND LOW DEWPOINTS - UP THERE RIGHT NOW.  
THEY WOULD NEED TO CLEAR OUT FOR FOG TO BECOME POSSIBLE.  
 
PREV...  
EXPECT SCATTERED, DIURNALLY-DRIVEN CONVECTION TO FORM DURING  
THE LATE AFTERNOON HOURS TODAY OVER THE SOUTHERN HALF OF THE  
STATE, IN THE MODERATELY UNSTABLE AIR MASS (WITH SFC BASED CAPE  
CLIMBING TO NEARLY 1500 J/KG) ALONG AND SOUTH OF REMNANT SFC-850  
MB FRONTAL BOUNDARY.  
 
HIGHEST POPS OF AROUND 50PCT WILL BE PAINTED ALONG THE MASON  
DIXON LINE, WHERE PWATS ARE HIGHEST. WEAK WINDS ALOFT AND 0-6KM  
SHEAR ONLY AROUND 15KTS INDICATE ANY STORMS WILL BE OF THE PULSE  
VARIETY WITH LITTLE RISK OF SEVERE WEATHER.  
 
THE DRY GROUND AND ABUNDANT SUNSHINE IN MOST PLACES HAD LED  
TO ANOTHER WARM DAY RELATIVE TO CLIMATOLOGY ACROSS THE NORTHERN  
HALF OF THE STATE, WITH HIGHS IN THE UPPER 80S POSSIBLE IN THE  
VALLEYS ALONG I-80. MORE CLOUD COVER AND SCATTERED CONVECTION  
SHOULD HOLD READINGS CLOSE TO AVERAGE ACROSS THE SOUTHERN  
COUNTIES.  
 
ANY SHOWERS/STORMS ACROSS SOUTHERN PA WILL DISSIPATE QUICKLY  
WITH THE LOSS OF HEATING THIS EVENING, THEN EXPECT DRY WEATHER  
THE REST OF THE NIGHT. AN APPROACHING UPPER TROUGH AND SURFACE  
LOW OVER THE OHIO VALLEY WILL SPREAD INCREASING CLOUDS INTO THE  
REGION OVERNIGHT, WITH AN OUTSIDE CHANCE OF A SHOWER REACHING  
SOMERSET COUNTY BY DAWN.  
 

 
   
SHORT TERM /8 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/
 
 
A SLOW MOVING SHORTWAVE AND ASSOCIATED WAVE OF SFC LOW PRESSURE  
WILL TRACK EASTWARD FROM THE OHIO VALLEY THIS WEEKEND.  
 
THERE REMAINS A RELATIVELY HIGH AMT OF MODEL SPREAD/FORECAST  
UNCERTAINTY REMAIN WITH REGARD TO HOW FAR NORTH THIS FEATURE AND  
ITS ASSOCIATED RAIN GET IN PA. HOWEVER, ALL GUIDANCE FAVORS THE  
HIGHEST POPS ACROSS THE SOUTHERN TIER COUNTIES LATE SATURDAY  
INTO EARLY SUNDAY IN ASSOCIATION WITH PASSAGE OF ANOMALOUS  
EASTERLY LOW LEVEL JET.  
 
WITH SURFACE LOW TRACKING SOUTH OF THE STATE AND ALL GUIDANCE  
SHOWING RELATIVELY STABLE AIR OVER PA, ANTICIPATE A STRATIFORM  
RAINFALL, RATHER THAN CONVECTION, AND LITTLE RISK OF FLOODING.  
THE BULK OF LATEST GUIDANCE INDICATE 24HR RAIN AMOUNTS OF  
AROUND AN INCH OR SO ARE POSSIBLE ACROSS THE SOUTHERN COUNTIES.  
 

 
   
LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/
 
 
UNSETTLED CONDS PERSIST INTO SUNDAY AS A SLOW MOVING WAVE OF LOW  
PRESSURE ALONG THE PERSISTENT FRONT OVER THE MASON DIXON LINE  
MOVES OFF OF THE NJ/DE COAST BY MIDDAY SUNDAY. THIS WILL BRING  
HIGHEST SHOWERS CHANCES TO THE SOUTHEAST, WITH PERHAPS SOME  
HEAVIER DOWNPOURS WHERE THEY LEAST NEED IT (THOSE AREAS WHICH  
RECEIVED SEVERAL INCHES FROM ISAIAS NEARLY TWO WEEKS AGO, AND  
MANY ADDITIONAL STORMS SINCE). IN ITS WAKE A RELATIVE LULL IN  
THE PRECIP IS SEEN LATER SUNDAY INTO MONDAY MORNING BEFORE  
A COLD FRONT IS PROGGED TO SWEEP THROUGH THE COMMONWEALTH  
MONDAY, USHERING IN COOLER AND DRIER WEATHER.  
 
THE CLIMATE PREDICTION CENTER 6-10 TEMPERATURE OUTLOOK FAVORS  
BELOW NORMAL TEMPERATURES IN CENTRAL PA. THIS WILL BE A WELCOME  
RELIEF AFTER A PROLONGED STRETCH OF WARM WEATHER. ADDITIONALLY,  
THE ARRIVAL OF HIGH PRESSURE BY THE MIDDLE OF NEXT WEEK SEEMS TO  
FAVOR A DRIER THAN NORMAL STRETCH FOR A LITTLE BIT.  
 
PRECIPITATION CHANCES RAMP UP AGAIN ACROSS THE SOUTHERN TIER BY  
LATE WEEK, BUT NO SIGNIFICANT IMPACTS ARE EXPECTED.  
 

 
   
AVIATION /02Z SATURDAY THROUGH WEDNESDAY/
 
 
AT 23Z, CUMULUS CLOUDS ARE ALREADY DISSIPATING ACROSS THE AREA,  
AS WE LOSE THE HEATING OF THE DAY. SOME HIGH CLOUDINESS IS  
DRIFTING EASTWARD OVERHEAD, WHICH IS DEBRIS FROM STORMS OVER  
THE MIDWEST AND OHIO VALLEY.  
 
EXPECTING GENERALLY VFR CONDS ACROSS CENTRAL PA OVERNIGHT, WITH  
LITTLE MORE THAN SOME HIGH AND MID-LEVEL CLOUDS PASSING  
OVERHEAD.  
 
SATURDAY WILL START OUT WITH VFR CONDS AREA-WIDE, AND WILL  
PROBABLY REMAIN THAT WAY ALL DAY ACROSS THE EAST. HOWEVER,  
CLOUDS WILL BUILD THROUGH THE DAY AND SHOWERS ARE POSSIBLE BY  
AFTERNOON ACROSS THE WESTERN HIGHLANDS.  
 
OUTLOOK...  
 
SUN...REDUCTIONS POSS IN SHOWERS/STORMS.  
MON...STILL A SLIGHT CHANCE OF SHOWERS/STORMS.  
TUE...GENERALLY VFR CONDS.  
WED...A FEW SHOWERS AND BRIEF REDUCTIONS POSS ACROSS THE SE.  
 

 
   
CLIMATE
 
 
A DAILY RECORD HIGH TEMPERATURE OF 87 DEGREES WAS TIED AT  
BRADFORD ON 8/13. THE PREVIOUS RECORD WAS SET IN 1988.  
 

 
   
CTP WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
SYNOPSIS...LAMBERT  
NEAR TERM...LAMBERT/DANGELO  
SHORT TERM...LAMBERT/FITZGERALD  
LONG TERM...DEVOIR/GARTNER  
AVIATION...EVANEGO  
CLIMATE...  
 
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