237  
FXUS61 KCTP 081741  
AFDCTP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE STATE COLLEGE PA  
1241 PM EST THU DEC 8 2022  
   
SYNOPSIS
 
 
HIGH PRESSURE TO OUR NORTH WILL BRING SEVERAL DAYS OF DRY AND  
GRADUALLY COLDER WEATHER INTO SATURDAY. A SHORTWAVE TROUGH WILL  
MOVE ACROSS THE STATE FROM THE WEST LATER IN THE WEEKEND. A  
PERIOD OF LIGHT MIXED PRECIPITATION COULD RESULT SATURDAY NIGHT  
AND SUNDAY. UPPER LEVEL RIDGING IS THEN EXPECTED TO MOVE IN WITH  
FAIR WEATHER FOR MUCH OF NEXT WEEK.  
 

 
   
NEAR TERM /UNTIL 8 PM THIS EVENING/
 
 
FORECAST IS VERY STABLE EXCEPT FOR THE NEAR TERM TEMPS WHICH ARE  
INTO THE L50S OVER THE FAR SE. THE THICK CLOUD COVER AND SLIGHT  
CAA WILL KEEP TEMPS FROM RISING MORE THAN ANOTHER DEGREE OR TWO  
THIS AFTN.  
 
PREV...  
A FAST ZONAL UPPER LEVEL JET FROM THE MID MISS VALLEY TO THE  
MIDDLE ATLANTIC REGION WILL RIDE OVER A SURFACE RIDGE EXTENDING  
SOUTH FROM HIGH PRESSURE, DRIFTING AFTERNOON ONTARIO TODAY.  
 
SHALLOW STRATO CU COVERING THE BULK OF THE CWA NORTH AND WEST  
OF THE INTERSTATE 81 CORRIDOR WILL SLOWLY ERODE FROM SE TO NW  
THIS AFTERNOON AND EVENING.  
 
THE CLOUDS WILL BE TOO WARM AND SHALLOW TO SUPPORT ANYTHING  
MORE THAT PATCHY DRIZZLE ON THE WINDWARD SIDE AND CRESTS OF THE  
RIDGES, WHILE VALLEY LOCATIONS WILL STAY DRY.  
 
WARM ADVECTION ALOFT PRECEDING AN APPROACHING SHORTWAVE IS  
LIKELY SPREAD CIRRUS, THEN ALTOCU ACROSS THE REGION DURING LATE  
MORNING AND AFTERNOON HOURS TODAY.  
 
MIXING DOWN MODEL 925MB TEMPS OF 0-3C YIELDS EXPECTED HIGHS  
RANGING FROM AROUND 40F OVER THE NORTHERN MOUNTAINS TO THE LOW  
50S ACROSS THE LOWER SUSQ VALLEY. THESE READINGS WILL BE 4-6F  
ABOVE NORMAL FOR THE DATE.  
 

 
   
SHORT TERM /8 PM THIS EVENING THROUGH 6 PM FRIDAY/
 
 
LOW-LEVEL RIDGING INTO THE STATE FROM THE NORTH WILL COMBINE  
WITH DRY NWRLY FLOW ALOFT TO PROVIDE US WITH MAINLY CLEAR SKIES  
WITH JUST A FEW PERIODS OF THIN CIRRUS OR PATCHY ALTOCU CLOUDS.  
 
WINDS WILL BE LIGHT FROM THE NORTH TO NORTHEAST TONIGHT THROUGH  
FRIDAY WITH TEMPS LOWERING TO NEAR NORMAL VALUES TONIGHT AND  
FRIDAY (WHICH IS THE MID 30S (NORTH) TO THE MID 40S (SOUTHERN  
VALLEYS).  
 
LOWS TONIGHT WILL BE IN THE MID 20S (CENTRAL AND NORTHERN MTNS TO  
BETWEEN 30-32F IN THE SOUTHERN VALLEYS.  
 

 
   
LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/
 
 
WARM ADVECTION PRECEDING A SHORTWAVE APPROACHING FROM THE LOWER  
GRT LKS SHOULD SPREAD THICKENING CLOUDS AND PERHAPS A BIT OF  
LIGHT PRECIPITATION INTO THE AREA FRIDAY NIGHT. HOWEVER, ALL  
GUIDANCE INDICATES THIS FEATURE WILL BE WEAKENING AS IT MOVES  
EAST AND WILL ENCOUNTER SOME FAIRLY DRY AIR OVER CENTRAL PA.  
THEREFORE, POPS REMAIN LOW AND CONCENTRATED OVER THE SOUTHWEST  
PART OF THE FORECAST AREA, WHERE MARGINALLY COLD MODEL SOUNDINGS  
POINT TOWARD MIXED PTYPE.  
 
UPPER LEVEL RIDGING SHOULD SUPPORT FAIR AND MILD CONDITIONS  
SATURDAY. FOCUS THEN SHIFTS TO A MORE POTENT SHORTWAVE  
APPROACHING FROM THE LOWER GRT LKS. STRONG WARM ADVECTION AT THE  
NOSE OF LOW LEVEL JET, COMBINED WITH UPPER LEVEL DIVERGENCE  
AHEAD OF THE SHORTWAVE, COULD SUPPORT A LIGHT TO MODERATE  
PRECIP EVENT ACROSS UPSTATE NY/NORTHERN PA LATE SAT NIGHT INTO  
PART OF SUNDAY. BORDERLINE MODEL SOUNDINGS INDICATE PTYPE COULD  
BE EITHER RAIN OR SNOW, WITH THE BEST CHANCE OF ACCUMULATING  
SNOW OVER THE NORTHERN MOUNTAINS, WHERE ENSEMBLE WSUP VIEWER  
INDICATES A 50-60PCT CHANCE OF AT LEAST 1 INCH.  
 
ALL MEDIUM RANGE GUIDANCE SUPPORTS FAIR AND SEASONABLE  
CONDITIONS EARLY NEXT WEEK ASSOCIATED WITH UPPER LEVEL RIDGING.  
THE LATEST GEFS AND ECENS BOTH TRACK A DEEP SURFACE LOW WEST OF  
PA THROUGH THE GRT LKS THE SECOND HALF OF NEXT WEEK, LIKELY  
SPREADING PRECIPITATION INTO THE REGION NEXT WEDNESDAY OR  
THURSDAY. A SURFACE HIGH AND POOL OF RELATIVELY COLD AIR POISED  
NORTH OF NEW ENGLAND COULD POTENTIALLY RESULT IN AN INITIAL  
WINTRY MIX BEFORE A CHANGE TO RAIN.  
 

 
   
AVIATION /18Z THURSDAY THROUGH TUESDAY/
 
 
MOST OF THE AREA REMAINS VFR WITH ONLY MVFR CLOUDS IN THE NORMAL  
(JST/BFD) TERMINALS. MULTIPLE CLOUD LAYERS WILL PASS OVER  
CENTRAL PA THIS AFTN AND TONIGHT AS A VERY WEAK TROUGH ALOFT  
PASSES TO OUR S. THERE IS A VERY SMALL CHC OF A SPRINKLE OR  
FLURRY TO REACH THE GROUND THIS EVENING, BUT 99PCT OF THE REAL  
PRECIPITATION SHOULD REMAIN TO THE S OF PA, AND CIELING IN JST  
AND AOO SHOULD REMAIN ABOVE IFR. VFR SHOULD CONTINUE THRU THE  
REST OF THE TAF VALID PERIOD AS CLEARING IS ANTICIPATED TONIGHT  
FOR THE SE AND EVERYWHERE ELSE ON FRIDAY.  
 
THE NEXT SIGNIFICANT WEATHER FEATURE IS ANTICIPATED TO MOVE IN  
FROM THE WEST SAT NIGHT OR SUN, AND BRING A PERIOD OF LIGHT  
PRECIP (MAINLY SN N, AND A MIX S).  
 
OUTLOOK...  
 
SAT NIGHT-SUN...REDUCTIONS TO IFR LIKELY IN -SN N, MIX S.  
 
MON...MVFR W, VFR E.  
 

 
   
CTP WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
SYNOPSIS...LAMBERT  
NEAR TERM...LAMBERT/DANGELO  
SHORT TERM...LAMBERT/FITZGERALD  
LONG TERM...LAMBERT/FITZGERALD  
AVIATION...DANGELO  
 
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