872  
FXUS61 KPHI 171856  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
256 PM EDT THU JUL 17 2025  
   
SYNOPSIS
 
 
A WEAK COLD FRONT WILL MOVE THROUGH THE REGION THIS EVENING,  
WITH HIGH PRESSURE TEMPORARILY BUILDING IN ITS WAKE. A SERIES OF  
DISTURBANCES WILL BRING UNSETTLED WEATHER THIS WEEKEND, UNTIL A  
STRONGER COLD FRONT CLEARS THE AREA SUNDAY. HIGH PRESSURE WILL  
SETTLE IN TO THE AREA FOR THE FIRST PART OF NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH FRIDAY/
 
 
A HOT AND OPPRESSIVELY HUMID DAY IS ONGOING WITH WIDESPREAD  
HEAT INDICES OF 100-105 BEING OBSERVED ACROSS MOST OF THE  
REGION. A HEAT ADVISORY REMAINS IN EFFECT THROUGH THIS EVENING.  
 
RELIEF IS ON THE WAY HOWEVER IN THE FORM OF A COLD FRONT  
MARCHING ACROSS PENNSYLVANIA AT THIS HOUR. THIS FRONT COULD ALSO  
TRIGGER A FEW SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND INTO  
THE EVENING. HOWEVER, THE FORCING ISN'T OVERTLY STRONG, AND  
WHILE WE HAVE AROUND 3500-4500 J/KG OF CAPE, SHEAR ISN'T  
ANYTHING TO WRITE HOME ABOUT, WITH EFFECTIVE BULK SHEAR AROUND  
20-25 KT OVER OUR AREA. MID-LEVEL LAPSE RATES ARE QUITE MEAGER  
AS WELL, ONLY AROUND 6-6.5 C/KM. IF SOMETHING COULD GET  
ORGANIZED, A STRONG TO SEVERE THUNDERSTORM CAN'T BE RULED OUT  
WITH THE AMOUNT OF MOIST AND UNSTABLE AIR IN PLACE. STEEP LOW-  
LEVEL LAPSE RATES COULD ALSO AID IN STRONGER DOWNDRAFTS.  
OVERALL, THE THREAT IS RATHER MARGINAL GIVEN THE LIMITING  
FACTORS IN PLAY, AND A MARGINAL (1/5) RISK IS IN PLACE FOR THE  
ENTIRE AREA. POPS RANGE FROM 20-40% ALONG AND WEST OF THE I-95  
CORRIDOR AND ABOUT 15-30% SOUTH AND EAST. MAIN THREAT WOULD BE  
DAMAGING WIND GUSTS FROM ABOUT 4 PM TO 9 OR 10 PM.  
 
THE COLD FRONT SHOULD SWING THROUGH TONIGHT WITH SKIES CLEARING  
OUT SOME AND HUMID AIR BEING SWEPT OUT OF THE REGION. IT STARTS  
TO FEEL MORE COMFORTABLE TONIGHT AS DEW POINTS FALL QUICKLY IN  
THE WAKE OF THE FRONT. LOWS GENERALLY RANGE FROM THE UPPER 60S  
TO LOW TO MID 70S. AREAS IN THE POCONOS COULD EVEN GET DOWN INTO  
THE 50S.  
 
WHILE THE COLD FRONT CLEARS OUR AREA OVERNIGHT, IT WILL STALL  
OUT JUST TO OUR SOUTH AND EAST. THIS COULD RESULT IN MORE CLOUDS  
AND A FEW SHOWERS/ISOLATED THUNDERSTORMS ACROSS THE DELMARVA  
PENINSULA AND FAR SOUTH JERSEY, AREAS THAT ARE IN CLOSER  
PROXIMITY TO THE STALLED BOUNDARY. NOT EXPECTING ANY SEVERE OR  
HYDRO THREATS HOWEVER. ELSEWHERE, IT WILL BE A RATHER QUIET DAY  
AND MUCH MORE COMFORTABLE THAN TODAY AS DEW POINTS WILL BE IN  
THE LOW TO MID 60S FOR MOST SPOTS, AND EVEN POTENTIALLY INTO THE  
50S NORTH OF I-78. HIGHS ARE MORE SEASONABLE, OR EVEN A FEW  
DEGREES BELOW NORMAL FOR TOMORROW-IN THE LOW TO MID 80S.  
 

 
   
SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/
 
 
AN UPPER-LOW INITIALLY OVER PORTIONS OF THE HUDSON BAY AND  
NORTHERN QUEBEC WILL SHIFT SLOWLY SOUTHEASTWARD THROUGH THE  
PERIOD. WITH RIDGING CENTERED OVER THE SOUTHEASTERN US, OUR  
REGION WILL INITIALLY HAVE WEAK ZONAL FLOW ALOFT AND NEUTRAL  
HEIGHTS. FRIDAY NIGHT, AN AREA OF LOW PRESSURE PASSING TO THE  
SOUTH COULD CONTINUE TO BRING LINGERING CHANCES FOR SHOWERS  
ACROSS PORTIONS OF THE DELMARVA, BUT HIGH PRESSURE OVER NEW  
ENGLAND SHOULD KEEP MOST OF THE AREA DRY. FRIDAY NIGHT LOWS  
SHOULD GENERALLY BE IN THE MID-UPPER 60S, WITH A FEW LOW 70S  
POSSIBLE, OUTSIDE OF THE POCONOS WHERE TEMPERATURES COULD FALL  
INTO THE UPPER 50S.  
 
A SUBTLE SHORTWAVE EMBEDDED IN THE ZONAL FLOW REGIME SHOULD  
PASS THROUGH THE AREA ON SATURDAY. AS THE SURFACE HIGH SHIFTS  
EAST OFF OF THE COAST, SHOWER AND STORM CHANCES WILL INCREASE  
ACROSS OUR ENTIRE AREA. AS OF RIGHT NOW, THE GREATEST CHANCE  
APPEARS TO BE FROM SATURDAY AFTERNOON INTO MUCH OF SATURDAY  
NIGHT. INSTABILITY LOOKS TO BE QUITE LIMITED WITH THIS SYSTEM,  
SO SEVERE WEATHER IS NOT ANTICIPATED AT THIS TIME. HOWEVER,  
THERE WILL BE ENOUGH MOISTURE TO WORK WITH TO SUPPORT AT LEAST  
SOME POTENTIAL FOR EXCESSIVE RAINFALL. AS SUCH, THE WEATHER  
PREDICTION CENTER HAS INTRODUCED A MARGINAL RISK (1 OF 4) ACROSS  
MOST OF OUR AREA FOR FLASH FLOODING.  
 
AS THE UPPER-LOW SHIFTS SOUTHEAST THROUGH THE WEEKEND, IT  
SHOULD BECOME MORE OF AN OPEN TROUGH WITH THE AXIS PIVOTING  
THROUGH NORTHERN NEW ENGLAND SUNDAY NIGHT. A SURFACE COLD FRONT  
WILL APPROACH THE AREA FROM THE NORTHWEST BY SUNDAY EVENING.  
SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE ACROSS MUCH OF THE  
AREA DURING THE AFTERNOON AND EVENING HOURS AHEAD OF THE FRONT.  
MODELS ARE HINTING AT SOME INSTABILITY AND WIND SHEAR THAT  
COULD LEAD TO SOME SEVERE POTENTIAL, SO THIS WILL NEED TO BE  
MONITORED IN THE COMING DAYS.  
 
THE COLD FRONT APPEARS LIKELY TO BRING IN A MUCH MORE PLEASANT  
AIRMASS. WHILE IT MAY NOT DROP TEMPERATURES TOO MUCH, IT SHOULD  
HELP WITH THE HIGH MOISTURE CONTENT WHICH HAS CONTRIBUTED TO THE  
OPPRESSIVE NATURE OF THE RECENT HEAT.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
WITH HIGH PRESSURE OVER THE AREA AND THE RECENT FRONTAL PASSAGE  
HAVING REDUCED BOTH TEMPERATURES AND DEWPOINTS ACROSS THE AREA,  
MONDAY AND TUESDAY SHOULD BOTH BE QUITE PLEASANT. PARTLY TO  
MOSTLY CLEAR SKIES AND FAIRLY LIGHT WINDS ARE EXPECTED.  
AFTERNOON HIGHS LOOK TO BE IN THE LOW-MID 80S BOTH DAYS, WITH  
OVERNIGHT LOWS GENERALLY IN THE LOW 60S.  
 
WHILE NO MAJOR STORM SYSTEMS ARE ANTICIPATED IN THE EXTENDED  
PERIOD, IT MAY BECOME SLIGHTLY MORE UNSETTLED WEDNESDAY INTO  
THURSDAY, WITH AT LEAST LOW CHANCES FOR AFTERNOON STORMS  
RETURNING. IN ADDITION, WE WILL LIKELY SEE TEMPERATURES START TO  
WARM AGAIN, WITH MOST LOCATIONS SEEING HIGHS APPROACHING 90  
AGAIN BY THURSDAY.  
 

 
   
AVIATION /19Z THURSDAY THROUGH TUESDAY/
 
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
TODAY...PRIMARILY VFR, THOUGH BRIEF RESTRICTIONS POSSIBLE AS  
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS DEVELOP LATER  
THIS AFTERNOON. ADDED VCTS GROUPS TO KRDG/KABE/KTTN FOR A FEW  
HOURS THIS AFTERNOON, WITH LESSER CHANCES AT OTHER TERMINALS,  
WHERE THUNDER WAS LEFT OUT OF THE TAFS. 30-40% CHANCE OF  
SHRA/TSRA AT KRDG/KTTN/KABE AND 15-25% ELSEWHERE. WINDS OUT OF  
THE SOUTHWEST 10-15 KT GUSTING 20- 25 KT. MODERATE CONFIDENCE.  
 
TONIGHT...VFR WITH DECREASING CLOUDS. SOUTHWEST WINDS GRADUALLY  
BECOMING NORTHWEST OVERNIGHT AROUND 5-10 KT FOLLOWING FRONTAL  
PASSAGE. HIGH CONFIDENCE.  
 
FRIDAY...VFR. NORTHWEST WINDS 5-10 KT. HIGH CONFIDENCE.  
 
OUTLOOK...  
 
FRIDAY NIGHT...VFR. NO SIGNIFICANT WEATHER EXPECTED.  
 
SATURDAY THROUGH SUNDAY...SUB-VFR CONDITIONS WILL BE POSSIBLE  
AT TIMES IN SCATTERED SHOWERS AND STORMS.  
 
SUNDAY NIGHT THROUGH TUESDAY...VFR. NO SIGNIFICANT WEATHER  
EXPECTED.  
 

 
   
MARINE
 
 
NO MARINE HEADLINES IN PLACE THROUGH FRIDAY. WINDS OUT OF THE  
SOUTHWEST THROUGH THIS EVENING BEFORE BECOMING NORTHWESTERLY  
OVERNIGHT. WIND SPEEDS OF AROUND 10-20 KT. SEAS 3 TO 4 FEET. A  
FEW THUNDERSTORMS POSSIBLE, ESPECIALLY NORTH OF LITTLE EGG  
INLET, THIS EVENING.  
 
OUTLOOK...  
 
NO MARINE HEADLINES ANTICIPATED. WINDS ARE EXPECTED TO REMAIN  
BELOW 25 KT WITH SEAS REMAINING BELOW 5 FT. SCATTERED SHOWERS  
AND STORMS WILL BE POSSIBLE SATURDAY AND SUNDAY.  
 
RIP CURRENTS...  
 
FOR TODAY, SOUTHWEST WINDS INCREASE TO 15-25 MPH WITH BREAKING  
WAVES AROUND 1-3 FEET AND A BUILDING SOUTHERLY 3-4 FOOT SWELL  
AROUND 6-7 SECONDS. AS A RESULT, HAVE UPGRADED CAPE MAY AND  
ATLANTIC COUNTY BEACHES TO MODERATE DUE TO MORE PERPENDICULAR  
SWELL AND HAVE MAINTAINED A LOW RISK FOR RIP CURRENTS FOR THE  
REMAINDER OF THE JERSEY SHORE AND DELAWARE BEACHES.  
 
FOR FRIDAY, NORTHWEST WINDS AROUND 5-10 MPH WITH BREAKING WAVES  
AROUND 1-2 FEET AND A SOUTHERLY 2 FOOT SWELL AROUND 6-7 SECONDS.  
AS A RESULT, HAVE MAINTAINED A LOW RISK FOR RIP CURRENTS AT ALL  
BEACHES.  
 
RIP CURRENTS OCCUR OFTEN IN THE VICINITIES OF JETTIES AND PIERS  
AND THE SPEED OF THE CURRENTS ARE GENERALLY MAXIMIZED AT LOW  
TIDES.  
 
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI  
 

 
   
PHI WATCHES/WARNINGS/ADVISORIES
 
 
PA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ060>062-070-  
071-101>106.  
NJ...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ001-007>010-  
012>027.  
DE...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DEZ001>004.  
MD...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MDZ012-015-019-  
020.  
MARINE...NONE.  
 

 
 

 
 
SYNOPSIS...COOPER  
NEAR TERM...HOEFLICH  
SHORT TERM...COOPER  
LONG TERM...COOPER  
AVIATION...COOPER/HOEFLICH  
MARINE...COOPER/HOEFLICH  
 
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