496  
FXUS61 KPHI 070551  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
151 AM EDT FRI AUG 7 2026  
   
WHAT HAS CHANGED  
 
THE POTENTIAL FOR SHOWERS AND STORMS OVERNIGHT HAS ENDED.  
 
UPDATED AVIATION SECTION FOR 06Z TAFS.  
 
TIMING OF STORMS FRIDAY EVENING HAS TRENDED SLIGHTLY LATER.  
 
 
   
KEY MESSAGES  
 
1. HOT AND VERY HUMID CONDITIONS ARE EXPECTED TO PERSIST  
THROUGH TUESDAY OF NEXT WEEK. A HEAT ADVISORY IS IN EFFECT FOR  
PORTIONS OF THE AREA.  
 
2. THERE ARE DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS  
THROUGH SATURDAY, AS WELL AS MUCH OF NEXT WEEK. THERE IS AT  
LEAST A MARGINAL RISK EACH DAY FOR LOCALIZED HEAVY RAINFALL  
LEADING TO FLASH FLOODING AND LOCALLY DAMAGING WIND GUSTS WITH  
ANY STRONGER THUNDERSTORMS THAT DEVELOP.  
 
 
   
DISCUSSION  
 
KEY MESSAGE 1...HOT AND VERY HUMID CONDITIONS ARE EXPECTED TO  
PERSIST THROUGH TUESDAY OF NEXT WEEK. A HEAT ADVISORY IS IN  
EFFECT FOR PORTIONS OF THE AREA.  
 
A RELATIVELY STAGNANT SYNOPTIC PATTERN IS DEVELOPING ACROSS OUR  
REGION. QUASI ZONAL MID AND UPPER LEVEL FLOW WILL BE IN PLACE  
THROUGH THE MIDDLE OF NEXT WEEK AS BERMUDA HIGH PRESSURE  
PERSISTS OFFSHORE. THIS WILL KEEP A STEADY STREAM OF VERY WARM  
AND MOIST AIR IN PLACE ACROSS THE REGION THROUGH THE PERIOD.  
 
A PROLONGED PERIOD OF HOT AND, MOST NOTABLY, VERY HUMID  
CONDITIONS IS EXPECTED TO REMAIN IN PLACE FOR THE NEXT SEVERAL  
DAYS. WE LOOK TO HAVE A WEAK COLD FRONTAL PASSAGE EARLY SUNDAY,  
USHERING IN SLIGHTLY DRIER AIR. THIS WILL GIVE SOME SLIGHT  
REPRIEVE FROM THE EXCESSIVE HUMIDITY, THOUGH HIGHS WILL STILL BE  
IN THE UPPER 80S TO LOW 90S. MOISTURE ADVECTION WILL RETURN  
AGAIN BY MONDAY THOUGH, AND HOT AND VERY HUMID CONDITIONS ARE  
ANTICIPATED TO RETURN MONDAY THROUGH TUESDAY. A SOMEWHAT  
STRONGER COLD FRONT LOOKS TO COME THROUGH LATE TUESDAY OR  
WEDNESDAY, WHICH WILL HELP BREAK THE EXCESSIVE HEAT AND HUMIDITY  
SOME.  
 
A HEAT ADVISORY REMAINS IN EFFECT FOR PORTIONS OF EASTERN  
PENNSYLVANIA, MUCH OF NEW JERSEY EXCEPT THE FAR SOUTHERN  
COUNTIES, AS WELL AS NEW CASTLE COUNTY, DELWARE.  
 
KEY MESSAGE 2...THERE ARE DAILY CHANCES FOR SHOWERS AND  
THUNDERSTORMS THROUGH SATURDAY, AS WELL AS MUCH OF NEXT WEEK.  
THERE IS AT LEAST A MARGINAL RISK EACH DAY FOR LOCALIZED HEAVY  
RAINFALL LEADING TO FLASH FLOODING AND LOCALLY DAMAGING WIND  
GUSTS WITH ANY STRONGER THUNDERSTORMS THAT DEVELOP.  
 
DIURNALLY DRIVEN INSTABILITY WILL MOSTLY BE IN THE 1000-2000  
J/KG EACH AFTERNOON THROUGH THE NEXT SEVERAL DAYS ALONG WITH  
PWATS IN THE 1.5-2" RANGE. MEAN FLOW WILL BE PREDOMINANTLY  
SOUTHWESTERLY AND RELATIVELY WEAK THROUGH SATURDAY. THIS WILL  
SUPPORT A CONTINUED LOCALIZED HEAVY RAINFALL THREAT WITH  
POTENTIAL FOR FLASH FLOODING, ALTHOUGH WATER LOADED DOWNDRAFTS  
COULD CAUSE LOCALIZED WIND DAMAGE. AREAS WITH VERY SATURATED  
GROUND FROM RECENT RAINS WILL BE MOST PRONE TO EXPERIENCING  
TREES FALLING.  
 
ON FRIDAY, A MID LEVEL SHORTWAVE TROUGH IS EXPECTED TO APPROACH  
LATE IN THE DAY, PROVIDING MORE FORCING (AS COMPARED TO TODAY).  
AS SUCH, STORM COVERAGE IS EXPECTED TO BE MORE WIDESPREAD, AND  
STORMS SHOULD BE MORE ORGANIZED ALTHOUGH BULK SHEAR VALUES ARE  
STILL RELATIVELY MODEST (UP TO 25 KT). ALL THAT BEING SAID,  
CONTINUED CONCERN FOR HEAVY RAIN/FLASH FLOODING AND DAMAGING  
WINDS. TO A LESSER EXTENT, THERE IS ALSO SOME RISK FOR HAIL,  
GIVEN THE DEEP UNSTABLE LAYER.  
 
DETAILS FOR SATURDAY'S CONVECTION REMAIN UNCLEAR, BUT WE COULD  
CERTAINLY END UP WITH SOME POTENTIAL FOR FLASH FLOODING AND  
SEVERE STORMS AGAIN. CURRENT INDICATIONS IN THE GUIDANCE SUPPORT  
A LATER TIMING OF STORMS DURING THE EVENING OR EVEN OVERNIGHT  
DEPENDING ON THE TIMING OF A WEAK COLD FRONT AND SHORTWAVE  
TROUGH.  
 
WE LOOK TO HAVE A WEAK COLD FRONTAL PASSAGE BY EARLY SUNDAY,  
USHERING IN SLIGHTLY DRIER AIR. THIS COMBINED WITH SUBTLE  
SUBSIDENCE ALOFT WILL HELP BRIEFLY LIMIT CONVECTION POTENTIAL ON  
SUNDAY AND ALSO GIVE SOME SLIGHT REPRIEVE FROM THE EXCESSIVE  
HUMIDITY, THOUGH HIGHS WILL STILL BE IN THE UPPER 80S TO LOW  
90S. MOISTURE AND FORCING ALOFT WILL RETURN BY MONDAY AS MEAN  
FLOW SHIFTS MORE WESTERLY AND MID LEVEL FLOW INCREASES. THIS  
SHOULD RESULT IN A GREATER SEVERE THUNDERSTORM THREAT COMPARED  
TO THIS WEEK, AND PERHAPS SLIGHTLY LOWER FLASH FLOODING THREAT,  
BUT THE DETAILS INTO THE PERIOD EARLY NEXT WEEK REMAIN UNCLEAR.  
LONG STORY SHORT, MONDAY AND TUESDAY LOOK TO CONTINUE THE HOT  
AND HUMID CONDITIONS AND DAILY THUNDERSTORM CHANCES.  
 
A SOMEWHAT STRONGER COLD FRONT LOOKS TO COME THROUGH LATE  
TUESDAY OR WEDNESDAY, WHICH WILL HELP BREAK THE EXCESSIVE HEAT  
AND HUMIDITY SOME, BUT THE PATTERN ALOFT MAY STILL SUPPORT  
DIURNALLY DRIVEN CONVECTION.  
 
 
   
AVIATION /06Z FRIDAY THROUGH TUESDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
THROUGH 12Z...PREVAILING VFR EXPECTED. SOME FOG DEVELOPMENT IS  
POSSIBLE, ESPECIALLY AT KRDG, KABE, AND KTTN, BUT CANNOT RULE  
OUT SOME PATCHY FOG AT SOME OTHER TERMINALS. WINDS WILL  
GENERALLY SETTLE OUT OF THE SOUTHWEST AROUND 5 KTS OR LESS, BUT  
MAY BECOME LIGHT AND VARIABLE AT TIMES. MODERATE CONFIDENCE AS  
A WHOLE, LOW CONFIDENCE ON ANY FOG DEVELOPMENT.  
 
FRIDAY...VFR EXPECTED FOR MOST OF THE DAY. SCATTERED SHOWERS  
AND THUNDERSTORMS WILL DEVELOP LATE IN THE DAY, PRIMARILY AFTER  
20-23Z FROM WEST TO EAST. HIGHLIGHTED THIS WITH VCTS AT ALL TAF  
SITES, AND INCLUDED TEMPO GROUPS FOR IFR VISIBILITY WHERE  
THUNDERSTORMS ARE MOST LIKELY. SOUTHWEST WINDS GENERALLY  
BETWEEN 5-10 KTS, LOCALLY UP TO 15 KTS. MODERATE TO HIGH  
CONFIDENCE.  
 
FRIDAY NIGHT...PRIMARILY VFR EXPECTED, HOWEVER RESTRICTIONS ARE  
POSSIBLE AT TIMES PRIOR TO 04Z WITH ANY SHOWERS OR  
THUNDERSTORMS.  
 
OUTLOOK...  
 
SATURDAY-SATURDAY NIGHT...MOSTLY VFR EXCEPT LOWER CONDITIONS  
POSSIBLE WITH AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS.  
 
SUNDAY-SUNDAY NIGHT...VFR CONDITIONS EXPECTED.  
 
MONDAY-TUESDAY...MOSTLY VFR EXCEPT LOWER CONDITIONS POSSIBLE  
WITH AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS.  
 
 
   
MARINE  
 
WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY  
CRITERIA THROUGH FRIDAY.  
 
OUTLOOK...  
 
FRIDAY NIGHT...GUSTY AND ERRATIC WINDS ARE POSSIBLE IN THE  
VICINITY OF ANY THUNDERSTORMS FRIDAY EVENING.  
 
SATURDAY-TUESDAY...CONDITIONS EXPECTED TO REMAIN BELOW ADVISORY  
LEVELS THROUGH TUESDAY OF NEXT WEEK.  
 
RIP CURRENTS...  
 
FOR FRIDAY...SOUTHWEST TO SOUTH WINDS AROUND 10 MPH WITH  
BREAKING WAVES IN THE SURF ZONE OF 1 TO 3 FEET. A MEDIUM PERIOD  
EAST TO SOUTHEAST SWELL CONTINUES (DOMINANT WAVE PERIOD OF 5-7  
SECONDS). OPTED TO GO WITH A LOW RISK FOR THE DEVELOPMENT OF  
DANGEROUS RIP CURRENTS AT ALL BEACHES.  
 
FOR SATURDAY...SOUTHWESTERLY WINDS CONTINUE AND SHOULD INCREASE  
SOME TO 10-20 MPH. BREAKING WAVES IN THE SURF ZONE ARE FORECAST  
TO INCREASE SOME, ESPECIALLY FOR THE JERSEY SHORE, AT 2 TO 4  
FEET. GIVEN THE INCREASING SURF AND SOUTHERLY WINDS, WENT WITH A  
MODERATE RISK FOR THE DEVELOPMENT OF DANGEROUS RIP CURRENTS FOR  
THE JERSEY SHORE. BREAKING WAVES SHOULD BE A LITTLE LOWER STILL  
FOR THE DELAWARE BEACHES, THEREFORE WENT WITH A LOW RISK FOR  
THE DEVELOPMENT OF DANGEROUS RIP CURRENTS.  
 
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI  
 
 
   
PHI WATCHES/WARNINGS/ADVISORIES  
 
PA...HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR PAZ070-071-102-104-  
106.  
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ060>062-101-  
103-105.  
NJ...HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR NJZ010-012>015-  
017>020-027.  
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ001-007>009.  
DE...HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR DEZ001.  
MD...NONE.  
MARINE...NONE.  
 
 
 
 
 
DISCUSSION...DESILVA/JOHNSON/ROBERTSON/STAARMANN  
AVIATION...DESILVA/JOHNSON/STAARMANN  
MARINE...GORSE/JOHNSON/MPS/STAARMANN  
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