078  
FXUS61 KCTP 011900  
AFDCTP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE STATE COLLEGE PA  
300 PM EDT SUN JUN 1 2025  
   
SYNOPSIS  
 
* FROST IS EXPECTED FOR THE ALLEGHENY PLATEAU TONIGHT, WITH  
PATCHY FROST IN THE LAURELS AND PERHAPS CENTRAL MOUNTAINS.  
* DRY CONDITIONS PREVAIL FOR THE FIRST HALF OF THE WEEK, BEFORE  
A RETURN TO SHOWERS AND THUNDERSTORMS BY THURSDAY.  
* A TREND TOWARDS MUCH WARMER, SUMMER-LIKE CONDITIONS IS  
FORESEEN THIS WEEK.  
 
 
   
NEAR TERM /THROUGH MONDAY/  
 
AS WE LOSE (HEATING OF) THE SUN, WE SHOULD ALSO LOSE THE THICK  
STRATOCU OVER THE CWA, LATEST IN THE NE, OF COURSE. THAT WILL  
LEAVE US WITH A FAIR AND COLD NIGHT FOR EARLY JUNE. WHILE WE  
LIKELY WON'T HIT ANY RECORD LOWS, IT WILL GET COLD AND WE LOSE  
THE WIND, TOO. THE EXPECTED MINS IN THE M30S OVER THE NW THIRD  
OF THE AREA SHOULD ALLOW AREAS OF FROST TO FORM EVEN THOUGH  
THERE WILL BE AN INCREASE IN SMOKE ALOFT THRU THE NIGHT. PATCHY  
FROST IS ALSO POSSIBLE IN THE COLD SINKS/VALLEYS/OPEN AREAS OF  
THE NEXT TIER OR TWO OF ZONES TO THE SE OF THERE INCLUDING THE  
LAURELS AND SOME OF THE RIDGE AND VALLEY REGION (JST-UNV-IPT).  
WE HAVE POSTED A FROST ADVY FOR THE NW, AND STRONGLY CONSIDERED  
ONE FOR THE NEXT FEW ZONES SE. HOWEVER, GUIDANCE TEMPS ARE A  
LITTLE HIGHER THERE ACROSS THE BOARD, AND GIVE US LESS  
CONFIDENCE IN GOING ANY COLDER.  
 
AFTER THE FROSTY START, WE SHOULD BE GOOD TO GET INTO THE 66-73F  
RANGE FOR MAXES ON MONDAY AS WE ADD ABOUT 2-3C ONTO 8H TEMPS AND  
WE MIX UP TO AND PAST 8H. BY THE END OF THE DAY, THE UPPER  
TROUGH AXIS SHOULD BE OFF TO OUR EAST AND THE SFC HIGH/RIDGE  
AXIS OVERHEAD.  
 
 
   
SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/  
 
SURFACE HIGH PRESSURE HOLDS THROUGH FIRM THROUGHOUT THE SHORT-  
TERM PERIOD BRINGING CONTINUED FAIR WEATHER MONDAY EVENING  
THOUGH THURSDAY MORNING. OVERALL WARMING TREND IS PROGGED BY ALL  
MODEL GUIDANCE TO CONTINUE THROUGH THE SHORT-TERM, TOO, WITH  
HIGH TEMPERATURES NEAR-AVERAGE ON MONDAY TREND WELL-ABOVE  
CLIMATOLOGICAL AVERAGES BY WEDNESDAY. RECENT RUNS OF THE  
VERTICALLY INTEGRATED SMOKE PRODUCT FROM THE HRRR OUTLINE  
INCREASING SMOKE ACROSS CENTRAL PENNSYLVANIA ON TUESDAY UNDER  
NORTHWESTERLY FLOW.  
 
 
   
LONG TERM /THURSDAY THROUGH SUNDAY/  
 
HIGH PRESSURE BEGINS TO SHIFT FURTHER EAST THURSDAY MORNING  
WITH MODEL GUIDANCE OUTLINING MODEST AGREEMENT IN A WEAK AREA OF  
LOW PRESSURE WEST OF THE AREA GRADUALLY MOVING CLOSER TO  
CENTRAL PENNSYLVANIA. SURGING PWATS AND LOWERING HEIGHTS AHEAD  
OF THIS AREA OF LOW-PRESSURE SUPPORT PRECIPITATION MENTIONS JUST  
AHEAD OF SUNRISE ON THURSDAY. AS LOW-PRESSURE APPROACHES AND  
BETTER MOISTURE SPREADS INTO THE AREA THURSDAY AFTERNOON,  
WIDESPREAD RAIN SHOWERS APPEAR INCREASINGLY LIKELY ON FRIDAY AS  
AN ASSOCIATED COLD FRONT APPROACHES THE AREA. COLD FRONT IS  
EXPECTED TO BE BEGINNING TO DECAY AT THIS JUNCTURE WITH LOWER  
SHEAR VALUES AND MARGINAL CAPE. GIVEN THESE PARAMETERS, LOW  
CONFIDENCE ON ANY SEVERE WEATHER CONCERNS ON THURSDAY.  
 
CONFIDENCE IN THE FORECAST BECOMES LOWER AFTER FRIDAY; HOWEVER,  
WITH ECMWF DETERMINISTIC GUIDANCE INDICATING DRIER CONDITIONS  
EARLY SATURDAY THROUGH THE END OF THE LONG-TERM FORECAST PERIOD.  
RECENT GFS DETERMINISTIC GUIDANCE DOES HOLD MOISTURE FURTHER  
INTO CENTRAL PENNSYLVANIA FOR THE FIRST HALF OF SATURDAY BEFORE  
TRENDING DRIER THROUGH THE END OF PERIOD. GIVEN THIS GUIDANCE,  
HAVE OPTED TO STICK CLOSE TO NBM GUIDANCE SATURDAY AND SUNDAY;  
HOWEVER, IN FUTURE CYCLES COULD REALISTICALLY SEE SUNDAY  
TRENDING DRIER OVERALL.  
 
 
   
AVIATION /19Z SUNDAY THROUGH FRIDAY/  
 
WIND STILL GUSTING TO 20-26KT AT MOST SITES DURING THE MIDDLE OF  
THE DAY, BUT WE WILL LOSE THE SUN AND ALMOST ALL, IF NOT ALL, OF  
THE WIND TONIGHT. THE THICK STRATOCU MAY HOLD A SPRINKLE IN THE  
THICKEST PART OF THE DECK. BUT, THESE SHOULD ALSO GO AWAY AS WE  
LOSE THE SUN. THE CLOUDS SHOULD ALSO SLINK NE AS THEY DISSOLVE.  
THERE COULD BE A TOUCH OF VALLEY FOG OVER THE NW, BUT THE  
DRYNESS OF THE AIRMASS WILL TRY TO BALANCE THAT OUT. WE HAVE HAD  
A FULL DAY OF DEEP MIXING AND DRYING OUT OF THE SOIL. NOT ENOUGH  
OF A THREAT OR CONFIDENCE TO PUT A MENTION OF FOG IN ANYWHERE  
(MAINLY BFD AND IPT WOULD BE THE SPOTS) AT THIS POINT. EXPECT  
THERE TO BE SOME DIURNAL CU POP UP TO THE EAST OF IPT MONDAY  
AFTN, BUT NOT ENOUGH TO MENTION. IT WILL BE A GOOD VFR DAY WITH  
A LIGHT WESTERLY WIND (GUSTS SHOULD ONLY BE 12-14KT AT THE  
WORST). VFR RULES INTO THE MIDDLE OF THE WEEK WITH HIGH PRESSURE  
OVERHEAD TO BEGIN WITH SLOWLY MOVING TO THE EAST.  
 
OUTLOOK...  
 
TUE-WED...VFR EXPECTED.  
 
THU...POTENTIAL BRIEF RESTRICTIONS IN SHRA/TSRA NW.  
 
FRI...NUMEROUS SHRA/TSRA, ESP NW. BRIEF REDUCTIONS TO MVFR AND  
IFR IN THE TSRA.  
 
 
   
CLIMATE  
 
MAY 2025 PRECIPITATION RANKINGS  
 
SITE 2025 | WETTEST MAY ON RECORD  
-----------------------------------------------------------  
HARRISBURG* 10.02" WETTEST | 9.71" IN 1989 (PREVIOUS)  
WILLIAMSPORT 7.18" 7TH WETTEST | 9.91" IN 1919  
ALTOONA* 7.34" WETTEST | 7.31" IN 1960 (PREVIOUS)  
STATE COLLEGE 7.56" T-7TH WETTEST | 9.45" IN 1894  
 
(* DENOTES THAT MAY 2025 SET A NEW RECORD IN PRECIPITATION IN  
THEIR RESPECTIVE LOCATIONS. THE PREVIOUS RECORD REMAINS LISTED  
UNDER THE "WETTEST MAY ON RECORD" COLUMN.)  
 
 
   
CTP WATCHES/WARNINGS/ADVISORIES  
 
FROST ADVISORY FROM 1 AM TO 7 AM EDT MONDAY FOR PAZ004>006-010-  
011-017-037.  
 
 
 
 
 
SYNOPSIS...DANGELO  
NEAR TERM...DANGELO  
SHORT TERM...NPB  
LONG TERM...NPB  
AVIATION...DANGELO  
CLIMATE...NPB  
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