418  
FXUS61 KPHI 252001  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
401 PM EDT WED JUN 25 2025  
   
SYNOPSIS
 
 
OUR SIGNIFICANT HEAT WAVE WILL START TO WIND DOWN TONIGHT AND  
THURSDAY. THE UPPER LEVEL RIDGE TO OUR SOUTHWEST WILL  
GRADUALLY WEAKEN AND ALLOW A BACK DOOR COLD FRONT TO TRACK  
THOUGH MUCH OF THE FORECAST AREA THURSDAY INTO FRIDAY. THE FRONT  
WILL THEN PUSH BACK TO THE NORTH AS A WARM FRONT ON SATURDAY  
AND SUNDAY WITH HIGH PRESSURE REMAINING IN CONTROL INTO MONDAY.  
ANOTHER COLD FRONT LOOKS TO CROSS THROUGH THE AREA ON TUESDAY.  
 

 
   
NEAR TERM /THROUGH THURSDAY/
 
 
THE END IS IN SIGHT. THE SLOW BREAK DOWN OF THE UPPER RIDGE IS  
EVIDENT IN THE MUCH GREATER COVERAGE OF CUMULUS TODAY COMPARED  
TO THE LAST TWO DAYS, WITH DECENT STORM COVERAGE NOW FIRING TO  
OUR WEST ACROSS CENTRAL PA. SOME OF THESE WILL LIKELY MAKE THEIR  
WAY INTO OUR REGION, AND SOME HOME GROWN STORMS ALSO APPEAR TO  
BE STARTING TO DEVELOP, BUT GENERALLY LOOKING AT FAIRLY  
SCATTERED COVERAGE GIVEN A RELATIVE LACK OF A TRUE FOCUSING  
MECHANISM. THAT SAID, WITH HIGH DCAPE, ANY STORM COULD BRING  
GUSTY, PERHAPS LOCALLY DAMAGING WINDS, SO ANY DARK CLOUDS SHOULD  
BE TAKEN SERIOUSLY THROUGH THIS EVENING.  
 
LATER TONIGHT, CONDITIONS STABILIZE, BUT ADVECTION OF WARMTH AND  
INSTABILITY AS THE RIDGE GRADUALLY CONTINUES TO BREAK DOWN AND A  
SURFACE FRONT APPROACHES FROM THE NORTH SUCH THAT SPOTTY SHOWERS  
AND EVEN A FEW THUNDERSTORMS MAY REDEVELOP LATE, ESPECIALLY  
ACROSS NORTHERN AREAS. LOWS WILL MOSTLY BE IN THE 70S, 60S  
POCONOS.  
 
FRONT STARTS TO TAKE ON A BACKDOOR CONFIGURATION (MOVING  
NORTHEAST TO SOUTHWEST) AS IT SLIDES INTO THE FORECAST AREA  
EARLY THURSDAY MORNING, BUT MAY STALL FOR A TIME SOMEWHERE NEAR  
OR JUST SOUTHWEST OF PHILADELPHIA BEFORE PUSHING FURTHER  
SOUTHWEST AND ENVELOPING THE WHOLE CWA IN THE COOLER MARITIME  
AIR MASS. THIS MEANS WE'LL HAVE A NOTABLE NORTHEAST TO  
SOUTHWEST TEMPERATURE AND HEAT INDEX GRADIENT, WITH DELMARVA  
STILL NEAR HEAT ADVISORY LEVELS BUT LOCATIONS FURTHER NORTH AND  
EAST LIKELY FALLING SHORT. FOR THIS REASON, HAVE ADDED A HEAT  
ADVISORY FROM WILMINGTON SOUTHWESTWARD. WITH JULY CRITERIA  
WOULD'VE LEFT OUT NEW CASTLE COUNTY, BUT SINCE JUNE CRITERIA IS  
5 DEGREES LOWER, THEY NEEDED TO BE INCLUDED. OTHERWISE, THE MAIN  
WEATHER FOCUS ON THURSDAY WILL CONTINUED SHOWER/T-STORM  
POTENTIAL. WITH THE BACKDOOR FRONT SLIPPING SOUTHWEST, SEVERE  
RISK WILL BE LESS AFTER THE FRONT PASSES, BUT THE HEAVY RAIN  
THREAT LOOKS LIKELY EVERYWHERE. HIGHS WILL RANGE FROM THE 70S IN  
THE POCONOS, NORTHERN NJ AND ALONG THE NORTHERN NJ COAST, 80S  
ACROSS OUR CENTRAL SWATH AND SOUTHERN COAST, AND NEAR OR ABOVE  
90 FROM WILMINGTON AD MILLVILLE SOUTH AND WEST.  
 

 
   
SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/
 
 
BACKDOOR FRONT PUSHES SOUTHWEST OF THE REGION THURSDAY NIGHT.  
THIS SHOULD BRING COOLER CONDITIONS, BUT AS WARM MOIST AIR RIDES  
OVER THE BOUNDARY, THE CHANCE OF SHOWERS AND T-STORMS WILL  
INCREASE. SEVERE WEATHER RISK LOOKS LOWER GIVEN RELATIVELY  
STABLE SURFACE CONDITIONS, BUT AMPLE MOISTURE COULD RESULT IN  
HEAVY DOWNPOURS. LOWS MOSTLY IN THE 60S, 50S POCONOS AND NEAR 70  
PARTS OF DELMARVA.  
 
A BRIEF REPRIEVE FROM THE HEAT IS EXPECTED ON FRIDAY AS THE  
BACKDOOR FRONT FULLY SETTLES TO OUR SOUTH AND HIGH PRESSURE  
SHIFTS ACROSS THE CANADIAN MARITIMES. EASTERLY FLOW WILL DEVELOP  
ACROSS THE AREA, LEADING WIDESPREAD CLOUDS AND COOLER  
TEMPERATURES. THE RIDGE ALOFT WILL BREAK DOWN AND SHIFT  
SOUTHEAST, LEADING TO WESTERLY FLOW ALOFT WILL BRING A FEW  
DISTURBANCES THROUGH THE DAY AND FRIDAY NIGHT, LEADING TO A  
CHANCE OF SHOWERS AND THUNDERSTORMS.  
 
BY SATURDAY, THE FRONT WILL BEGIN LIFTING BACK NORTHWARD AND  
LIKELY STALL NEAR THE AREA, WHILE ANOTHER FRONT BEGINS TO  
APPROACH THE AREA FROM THE NORTHWEST. AS THIS FRONT MOVES INTO  
THE AREA, SEVERAL SHORT WAVE/VORTICITY IMPULSES WILL MOVE ACROSS  
THE AREA WITH THE WESTERLY FLOW ALOFT. THIS ALL WILL HELP LEAD  
TO AN INCREASE OF SHOWERS AND THUNDERSTORMS LATER SATURDAY INTO  
SATURDAY NIGHT.  
 
TEMPERATURES RETURN TO NORMAL OR ABOVE NORMAL AGAIN FOR  
SATURDAY.  
 

 
   
LONG TERM /SUNDAY THROUGH WEDNESDAY/
 
 
ON SUNDAY, THE FRONT THAT MOVES INTO THE AREA ON SATURDAY WILL  
LIKELY STALL NEAR THE AREA, BEFORE LIFTING BACK NORTHWARD  
THROUGH MONDAY. MULTIPLE SHORT WAVE/VORTICITY IMPULSES WILL  
CONTINUE TO MOVE ACROSS THE AREA, LEADING TO A CHANCE OF SHOWERS  
AND THUNDERSTORMS FOR SUNDAY THROUGH MONDAY.  
 
ON TUESDAY, A COLD FRONT WILL SWEEP ACROSS THE AREA, LEADING TO  
AN INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS. ONCE THE  
FRONT MOVES SOUTH OF THE AREA TUESDAY NIGHT, RAIN CHANCES WILL  
DIMINISH THROUGH WEDNESDAY.  
 
TEMPERATURES THROUGH THE LONG TERM PERIOD WILL REMAIN NEAR OR  
ABOVE NORMAL.  
 

 
   
AVIATION /20Z WEDNESDAY THROUGH MONDAY/
 
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
REST OF TODAY...MAINLY VFR WITH FEW/SCT CLOUDS. VCTS LATER ON  
WITH SPOTTY SHOWERS/T-STORMS, BUT COVERAGE LOOKS RELATIVELY LOW.  
ANY STORM COULD REDUCE CONDITIONS BELOW VFR BRIEFLY. W-NW WINDS  
AROUND 5-10 KT. HIGH CONFIDENCE.  
 
TONIGHT...MAINLY VFR. BRIEF PERIOD OF SUB-VFR CONDITIONS  
POSSIBLE WITH AN ISOLATED SHOWER OR THUNDERSTORM, MAINLY IN THE  
EVENING. A SMALL CHANCE ALSO EXISTS FOR SOME REDUCTIONS TO VSBY  
IN MIST LATER AT NIGHT. WINDS BECOMING LIGHT AND VARIABLE.  
MODERATE CONFIDENCE.  
 
THURSDAY...MAINLY VFR. SPOTTY SHOWERS/T-STORMS POSSIBLE DURING  
THE DAY ESPECIALLY WESTERN TERMINALS. BETTER CHANCE AT NIGHT  
WITH ANY STORM POSSIBLY BRINGING SUB-VFR CONDITIONS. WINDS  
TURNING NORTHEASTERLY 5-10 KTS. LOW CONFIDENCE.  
 
OUTLOOK...  
 
FRIDAY-MONDAY...PERIODS OF SUB-VFR CONDITIONS EXPECTED AT TIMES  
THROUGH THE PERIOD. CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH  
THE PERIOD AS WELL, ESPECIALLY IN THE AFTERNOON AND EVENING  
HOURS.  
 

 
   
MARINE
 
 
NO MARINE HEADLINES EXPECTED THROUGH THURSDAY NIGHT. S WINDS  
AROUND 5-10 KTS THIS AFTERNOON WILL TURN NW TONIGHT AND THEN NE  
ON THURSDAY INTO THURSDAY NIGHT, INCREASING TO 10-15 KTS WITH  
SOME GUSTS UP TO 20 KTS. SEAS OF 2 FEET OR LESS TONIGHT,  
INCREASING TO 2-4 FEET BY THURSDAY NIGHT. SPOTTY GUSTY  
THUNDERSTORMS POSSIBLE, MAINLY THIS AFTERNOON/EVENING AND  
PERHAPS AGAIN THURSDAY AFTERNOON/EVENING.  
 
OUTLOOK...  
 
FRIDAY-MONDAY...NO MARINE HEADLINES EXPECTED.  
 
RIP CURRENTS...  
 
FOR THURSDAY, WINDS TURN ONSHORE AND INCREASE TO AROUND 10-20 MPH.  
SEAS SLOWLY BUILD AS WELL, GETTING TO AROUND 2 TO 3 FEET IN THE  
NORTHERN WATERS. WHILE THE PERIOD REMAINS 8 TO 9 SECONDS, THE  
ONSHORE WINDS AND INCREASING WAVE HEIGHTS IN THE SURF ZONE WILL  
RESULT IN A MODERATE RISK FOR THE DEVELOPMENT OF RIP CURRENTS FOR  
OCEAN AND MONMOUTH COUNTY, NJ. FARTHER SOUTH, WINDS WILL BE A BIT  
WEAKER WITH LOWER WAVE HEIGHTS IN THE SURF ZONE. THIS WILL RESULT IN  
A LOW RISK FOR THE DEVELOPMENT OF RIP CURRENTS FOR THURSDAY FOR  
ATLANTIC AND CAPE MAY COUNTY IN NEW JERSEY AND THE DELAWARE BEACHES.  
 
FOR FRIDAY, ONSHORE FLOW WILL CONTINUE WITH SEAS OFF THE NJ COAST  
BUILDING TO AROUND 3 TO 4 FEET. FOR THIS REASON, THE MODERATE RISK  
FOR THE DEVELOPMENT OF DANGEROUS RIP CURRENTS EXPANDS SOUTH TO  
ALSO INCLUDE ATLANTIC COUNTY IN NJ. FOR CAPE MAY COUNTY AND THE  
DELAWARE BEACHES THERE WILL CONTINUE TO BE A LOW RISK FOR THE  
DEVELOPMENT OF DANGEROUS RIP CURRENTS.  
 
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI  
 

 
   
TIDES/COASTAL FLOODING
 
 
WITH THE NEW MOON OCCURING TODAY, ASTRONOMICAL TIDES ARE HIGHER THAN  
NORMAL. SPOTTY MINOR TIDAL FLOODING WAS OBSERVED FOR THE IMMEDIATE  
COASTLINE AND BACK BAYS AS WELL AS WITHIN DELAWARE BAY LAST NIGHT  
(TUESDAY EVENING). GIVEN NO MAJOR CHANGES IN OVERALL WEATHER  
PATTERN, EXPECTING SPOTTY MINOR FLOODING AGAIN WITH THIS EVENING'S  
HIGH TIDE.  
 
THERE IS HIGHER CONFIDENCE IN ADVISORIES POTENTIALLY BEING NEEDED  
STARTING THURSDAY EVENING. WHILE WE GET AWAY FROM THE NEW MOON,  
ONSHORE FLOW WILL RESULT IN WATER PILING UP AND MORE WIDESPREAD  
MINOR TIDAL FLOODING FOR THE COASTAL AND DELAWARE BAY COMMUNITIES.  
 
NO TIDAL FLOODING IS EXPECTED WITHIN THE TIDAL DELAWARE RIVER OR  
CHESAPEAKE BAY.  
 

 
   
CLIMATE
 
 
NEAR RECORD BREAKING HEAT IS EXPECTED ACROSS THE AREA THROUGH  
TODAY. YESTERDAY (JUNE 24), ALL CLIMATE SITES SET OR TIED EITHER  
A RECORD HIGH TEMPERATURE, A RECORD WARMEST LOW TEMPERATURE, OR  
BOTH. SOME SITES ALSO SET MONTHLY WARM RECORDS. SOME SITES HAD  
THEIR FIRST 100 DEGREE DAY IN OVER A DECADE. SEE THE RECORD  
EVENT REPORTS (RERS) SENT OUT EARLIER THIS MORNING FOR MORE  
DETAILS. ONE MORE DAY TO GO IN THIS STRETCH OF EXTREME HEAT,  
WHERE SOME RECORDS COULD FALL.  
 
RECORD HIGH TEMPERATURES  
JUNE 25  
SITE RECORD/YEAR  
ALLENTOWN (ABE) 98/1923  
AC AIRPORT (ACY) 96/1997  
AC MARINA (55N) 95/1952  
GEORGETOWN (GED) 96/1952  
MOUNT POCONO (MPO) 91/1952  
PHILADELPHIA (PHL) 98/1952  
READING (RDG) 99/1943  
TRENTON (TTN) 99/1997  
WILMINGTON (ILG) 98/1894  
 
RECORD WARMEST LOW TEMPERATURES  
JUNE 25  
SITE RECORD/YEAR  
ALLENTOWN (ABE) 74/1923 & 1976  
AC AIRPORT (ACY) 80/1950  
AC MARINA (55N) 75/1997 & 2002  
GEORGETOWN (GED) 75/2019  
MOUNT POCONO (MPO) 69/1952  
PHILADELPHIA (PHL) 76/1909, 1976 & 2002  
READING (RDG) 75/1943 & 1949  
TRENTON (TTN) 75/1976  
WILMINGTON (ILG) 75/1976  
 

 
   
PHI WATCHES/WARNINGS/ADVISORIES
 
 
PA...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR  
PAZ060>062-070-071-101>106.  
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ054-055.  
NJ...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR NJZ001-  
007>010-012-013-015>023-027.  
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ014-024>026.  
DE...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR  
DEZ001>003.  
HEAT ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY FOR  
DEZ001.  
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DEZ004.  
MD...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR MDZ012-  
015-019-020.  
HEAT ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY FOR  
MDZ012-015-019.  
MARINE...NONE.  
 

 
 

 
 
SYNOPSIS...RCM/ROBERTSON  
NEAR TERM...RCM  
SHORT TERM...RCM/ROBERTSON  
LONG TERM...ROBERTSON  
AVIATION...RCM/ROBERTSON  
MARINE...FITZSIMMONS/RCM/ROBERTSON  
TIDES/COASTAL FLOODING...  
CLIMATE...  
 
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