061  
FXUS61 KCTP 012340  
AFDCTP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE STATE COLLEGE PA  
740 PM EDT TUE JUL 1 2025  
   
SYNOPSIS
 
 
* SHOWERS AND THUNDERSTORMS, SOME WITH LOCALLY HEAVY DOWNPOURS,  
WILL GRADUALLY DIMINISH THROUGH THE EVENING HOURS  
* DRIER/LESS HUMID/MORE COMFORTABLE CONDITIONS ARE LIKELY FOR  
MID TO LATE WEEK, WITH A HIGH CONFIDENCE OF DRY WEATHER AND  
SEASONABLE TEMPERATURES ON INDEPENDENCE DAY  
* TRENDING WARMER AND MORE HUMID THIS WEEKEND; UNSETTLED PATTERN  
RETURNS BY SUNDAY  
 

 
   
NEAR TERM /UNTIL 11 PM THIS EVENING/
 
 
*FLOOD WATCH IN EFFECT UNTIL 11PM EDT THIS EVENING FOR SOUTH  
CENTRAL PA  
 
615 PM UPDATE... THE MOST ROBUST CONVECTION IS NOW LARGELY ALONG  
AND EAST/SOUTHEAST OF A PRE-FRONTAL SURFACE TROUGH OVER THE  
COASTAL PLAIN, WHERE DEEPER INSTABILITY AND HIGHER PRECIPITABLE  
WATER VALUES EXIST. ALTHOUGH HIT AND MISS SHOWERS AND  
THUNDERSTORMS COULD STILL IMPACT CENTRAL PA THIS EVENING, AHEAD  
OF THE MAIN SURFACE COLD FRONT THAT WILL BE SLOWLY COMING  
THROUGH THE REGION, SEVERE STORMS WOULD SEEM EXTREMELY UNLIKELY,  
THUS THE CANCELLATION OF THE SEVERE THUNDERSTORM WATCH.  
 
GIVEN ONGOING RUNOFF ISSUES AND EXTREMELY WET ANTECEDENT  
CONDITIONS, PARTICULARLY NEAR AND SOUTH OF I-78/US-22 IN THE  
SUSQUEHANNA VALLEY, THE FLOOD WATCH WILL STAY IN TACT AT THIS  
TIME.  
 
PREVIOUS DISCUSSION... PEAK WIND GUSTS FROM WATER-LOADED  
DOWNDRAFTS OBSERVED SO FAR EARLY THIS AFTERNOON HAVE BEEN IN THE  
25-30KT RANGE. STEEPER LOW LEVEL LAPSE RATES ACROSS THE LOWER  
SUSQUEHANNA VALLEY SUGGEST A GREATER RISK FOR STRONG TO  
POTENTIALLY SEVERE WIND GUSTS. RADAR TRENDS HAVE BEEN INCREASING  
IN INTENSITY WITH EASTERN EXTENT. FAIRLY PROGRESSIVE STORM  
MOTIONS HAVE TENDED TO OFFSET FF RISK SO FAR, HOWEVER RAIN RATES  
HAVE BEEN VERY EFFICIENT AT >1"/HR.  
 
EARLIER DISCUSSION ISSUED: 1217 PM EDT TUE JUL 1 2025  
 
SEVERE T-STORM THREAT VIA SPC MCD #1529  
 
CONVECTION IS BUILDING TO THE EAST ACROSS SOUTHWEST INTO SOUTH  
CENTRAL PA AT MIDDAY AHEAD OF A LOW-AMPLITUDE SHORTWAVE TROUGH  
THAT IS PROGRESSING EAST ACROSS THE UPPER OH VALLEY. WHILE THERE  
IS SOME NEAR-TERM UNCERTAINTY OF HOW QUICKLY THIS INITIAL  
ACTIVITY WILL STRENGTHEN AMID WEAK DCAPE, THE DOWNSTREAM AIRMASS  
IS DESTABILIZING QUITE WELL WITH SFC TEMPS INTO THE MID 80S.  
THIS WILL YIELD AN UPTICK IN CONVECTIVE INTENSITY AS CLUSTERS  
IMPINGE ON RICHLY MOIST AIRMASS WHERE 70-75F SURFACE DEW POINTS  
ARE PERVASIVE. ALTHOUGH LOWER-LEVEL WINDS WILL REMAIN WEAK AND  
PREDOMINATELY VEERED, MODERATE MID TO UPPER-LEVEL WESTERLIES  
WILL SUPPORT ORGANIZED MULTICELLS CAPABLE OF PRODUCING MULTIPLE  
STRONG TO ISOLATED SEVERE GUST SWATHS. SCATTERED DAMAGING WINDS  
APPEAR LIKELY TOWARDS MID TO LATE AFTERNOON.  
 
A SEVERE TSTM WATCH IS LIKELY TO BE ISSUED BY 17Z/1PM.  
 
FLASH FLOODING: FF THREAT REMAINS LOCKED IN ACROSS SOUTH CENTRAL  
AND SOUTHEAST PA. 12Z IAD SOUNDING CAME IN WITH DAILY RECORD  
PWAT OF 2.07" ALONG WITH A DAILY RECORD WBZ 0 HEIGHT SUPPORTING  
A VERY DEEP WARM-CLOUD LAYER WITHIN THE LOWER TROPOSPHERE. THIS  
ENVIRONMENT ALONG WITH TALL/SKINNY CAPE PROFILES ARE HIGHLY  
REPRESENTATIVE OF A STRONG PROSPECT FOR NOT ONLY HEAVY RAIN, BUT  
SIGNIFICANT RATE DRIVEN CORES (2-3+ IN/HR) THAT CAN EFFICIENTLY  
DROP SEVERAL INCHES OF RAIN IN A VERY SHORT SPAN OF TIME. THE  
POTENTIAL MAGNITUDE OF RAIN/RATES COMBINED WITH VERY SATURATED  
ANTECEDENT CONDITIONS WITH LOCALLY 4-6" IN SOME SPOTS IN THE  
PAST 24 HRS SUGGEST SIGNIFICANT FLASH FLOODING IMPACTS ARE  
POSSIBLE. FROM A HISTORICAL PERSPECTIVE, THE WPC MODERATE RISK  
OF EXCESSIVE RAINFALL (RISK LEVEL 3 OUT OF 4) TYPICALLY ONLY  
OCCURS 5-6X A YEAR IN PA, AND THIS IS THE SECOND MDT RISK IN THE  
PAST 30 DAYS. WPC SHOULD SEND A NEW MPD WITH MORE DETAILS  
SHORTLY.  
 

 
   
SHORT TERM /11 PM THIS EVENING THROUGH FRIDAY/
 
 
SHOWER ACTIVITY SLOWLY SHIFTS TO THE SOUTHEAST TONIGHT WITH ANY  
POST FRONTAL CLEARING EXPECTED TO RESULT IN FOG FORMATION INTO  
WEDNESDAY MORNING. THE LATEST HREF ALSO SUGGESTS SOME LOW CLOUDS  
AND STRATUS MAY LINGER INTO THE EARLY MORNING WEDNESDAY.  
 
ON BALANCE, THIS PERIOD WILL FEATURE A DRYING TREND WITH LITTLE  
TO NO RAINFALL AND MORE COMFORTABLE HUMIDITY. BEST ODDS FOR A  
COUPLE OF PM SHOWERS/T-STORM WILL BE THURSDAY AFTERNOON  
ASSOCIATED WITH A SECONDARY COLD FRONT MOVING SOUTHEAST FROM  
EASTERN CANADA AND THE NORTHERN GREAT LAKES.  
 
WE CONTINUE TO HAVE HIGH CONFIDENCE/CONVICTION IN A REALLY NICE  
INDEPENDENCE DAY WITH A NEAR ZERO CHANCE FOR RAIN AND GREAT  
VIEWING FOR FIREWORKS. MIN TEMPS FRIDAY NIGHT WILL BE QUITE  
COMFORTABLE IN THE LOW 50S TO LOW 60S.  
 
HUMIDITY LEVELS START TO CREEP UPWARD TO START THE FIRST  
WEEKEND OF JULY; HOWEVER IT WILL REMAIN DRY WITH UNSETTLED  
WEATHER EXPECTED TO RETURN SUNDAY INTO EARLY NEXT WEEK.  
 

 
   
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/
 
 
LOW PRESSURE APPROACHING THE GREAT LAKES BY SUNDAY MORNING WILL  
BRING ABOUT INCREASING CHANCES FOR PRECIPITATION FOR THE SECOND  
HALF OF THE WEEKEND AND INTO THE BEGINNING OF NEXT WEEK.  
 

 
   
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
 
 
00Z UPDATE... AS A COLD FRONT SLICES THROUGH PA OVERNIGHT, ANY  
ISOLATED-WIDELY SCATTERED SHOWERS/THUNDERSTORMS SHOULD DIMINISH.  
BASED ON CURRENT RADAR COVERAGE, WE'VE ONLY RETAINED RESTRICTIVE  
SHOWER MENTIONS AT KBFD, KMDT, AND KLNS THIS EVENING.  
 
GIVEN WIDESPREAD RAINFALL THIS AFTERNOON AND EARLY EVENING, PLUS  
ONLY SLOW INFUSION OF DRIER AIR IN THE LOWER LEVELS OF THE  
ATMOSPHERE OVERNIGHT, PATCHES OF LOWER CLOUDS AND FOG SEEM  
LIKELY. WE HAVE THE HIGHEST CONFIDENCE IN THAT SCENARIO OVER  
THE ALLEGHENIES (KBFD AND KJST), WHERE SOME IFR IS EXPECTED.  
 
ON WEDNESDAY, A BETTER PUSH OF DRY AIR SHOULD RESULT IN VFR  
CONDITIONS AREA-WIDE (VERY HIGH CONFIDENCE).  
 
OUTLOOK...  
 
THU...PRIMARILY VFR; STRAY PM SHOWER/T-STORM POSSIBLE.  
 
FRI-SUN...AM FOG POSSIBLE; OTHERWISE VFR.  
 

 
   
CTP WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH UNTIL 11 PM EDT THIS EVENING FOR PAZ066.  
 

 
 

 
 
SYNOPSIS...STEINBUGL  
NEAR TERM...JUREWICZ/STEINBUGL  
SHORT TERM...STEINBUGL  
LONG TERM...BANGHOFF/NPB  
AVIATION...JUREWICZ/BOWEN  
 
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