331  
FXUS61 KPHI 271918  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
318 PM EDT THU AUG 27 2026  
   
WHAT HAS CHANGED  
 
FLOOD WATCH EXPANDED TO INCLUDE THE LEHIGH VALLEY AND BERKS  
COUNTY.  
 
A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR ALL OF NEW  
JERSEY AND PORTIONS OF DELAWARE AND EASTERN PENNSYLVANIA  
THROUGH 8 PM THIS EVENING.  
 
THE THREAT FOR FLASH FLOODING IS ONGOING AND WILL CONTINUE  
THROUGH THE AFTERNOON WITH NUMEROUS REPORTS OF FLOODING ACROSS  
NEW JERSEY AND EASTERN PENNSYLVANIA.  
 
UPDATED THE AVIATION SECTION FOR THE 06Z TAFS.  
 
 
   
KEY MESSAGES  
 
1. THE THREAT OF STRONG TO SEVERE THUNDERSTORMS AND FLASH  
FLOODING WILL CONTINUE THROUGH THIS EVENING.  
 
2. A COLD FRONT IS EXPECTED TO PASS THROUGH THE AREA ON FRIDAY.  
 
 
   
DISCUSSION  
 
KEY MESSAGE 1...THE THREAT OF STRONG TO SEVERE THUNDERSTORMS AND FLASH  
FLOODING WILL CONTINUE THROUGH THIS EVENING.  
 
WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUE TO IMPACT MUCH OF  
NEW JERSEY AND PORTIONS OF EASTERN PENNSYLVANIA AND DELAWARE  
THIS AFTERNOON. THE GREATEST THREAT FROM THESE STORMS WILL  
CONTINUE TO BE LOCALIZED FLASH FLOODING, WITH MANY REPORTS OF  
ROAD CLOSURES DUE TO HIGH WATER ALREADY. SOME STORMS MAY ALSO BE  
STRONG TO SEVERE WITH LARGE HAIL AND DAMAGING WINDS. A SEVERE  
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 8 PM.  
 
THE LATEST HIRES GUIDANCE SUGGESTS THAT HEAVIEST PRECIPITATION  
WILL BE GENERALLY ALONG THE I-95 CORRIDOR AND POINTS NORTHWEST.  
HIRES GUIDANCE HAS ALSO POINTED TO AREAS ALONG THE I-78 CORRIDOR  
POTENTIALLY SEEING HEAVY RAINFALL AMOUNTS AS WELL. GENERALLY  
AROUND 1-2 INCHES OF RAIN WITH LOCALIZED QPF VALUES IN EXCESS OF  
3 INCHES. WIDESPREAD FLASH FLOODING STILL SEEMS UNLIKELY, BUT  
THE LOCALIZED THREAT REMAINS ELEVATED. THE FLOOD WATCH REMAINS  
IN EFFECT FOR MOST OF NJ AND THE I-95 CORRIDOR.  
 
FOR SEVERE HAZARDS, LATEST CAMS AND HREF GUIDANCE SHOW SBCAPE  
VALUES REMAINING AROUND 1500-2500 J/KG WITH ENSEMBLE MAXIMUMS  
IN EXCESS 3000 J/KG. DEEP LAYER SHEAR FORECASTS REMAIN AROUND  
30KT WITH A STRONGLY VEERING PROFILE ALOFT. BOUNDARY LAYER FLOW  
IS NOT PARTICULARLY STRONG BUT SURFACE WINDS ARE MORE BACKED  
THAN PREVIOUS FORECASTS SO AN ISOLATED TORNADO IS POSSIBLE  
PRIMARILY ALONG AND WEST OF I-95. THAT SAID, DAMAGING WIND GUSTS  
AND HAIL WILL REMAIN THE GREATEST THREAT. DOMINANT MODE SHOULD  
BE MULTICELL CONVECTION BUT A SUPERCELL CAN'T BE RULED OUT  
ESPECIALLY WHERE CLOUD BEARING SHEAR IS MAXIMIZED. SPC HAS  
EXPANDED THE AREA OF A SLIGHT RISK (2 OUT OF 5) TO NOW INCLUDE  
MUCH OF THE AREA.  
 
KEY MESSAGE 2...A COLD FRONT IS EXPECTED TO PASS THROUGH THE  
AREA ON FRIDAY.  
 
THE TIMING OF THIS COLD FRONT WILL BE CRITICAL IN THE RISK FOR  
THUNDERSTORM HAZARDS. THERE ARE DIFFERENCES BETWEEN MODELS IN  
BOTH THE TIMING, AND IF THIS WILL BE A SINGLE COLD FRONT, OR AN  
INITIAL COLD FRONT WITH A REINFORCING SHOT OF COLD AIR ADVECTION  
COMING IN BEHIND IT. SATURDAY AND SUNDAY APPEAR TO BE DRY ACROSS  
MOST OF THE AREA WITH THE EXCEPTION OF SOUTHERN AREAS SATURDAY  
WHERE LOW PROBABILITIES OF SHOWERS AND STORMS WILL EXIST.  
 
 
   
AVIATION /18Z THURSDAY THROUGH TUESDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
THURSDAY...PERIODS OF MVFR OR LOWER DUE TO SCATTERED TO NUMEROUS  
SHOWERS AND THUNDERSTORMS. CONTINUE TO MENTION VCTS FOR THE I-95  
CORRIDOR WITH PROB30 OR TEMPO GROUPS FOR TSRA. CONFIDENCE HAS  
INCREASED THAT THERE WILL BE MULTIPLE ROUNDS OF STORMS WITH  
FREQUENT LIGHTNING AND LOW CEILINGS, WHICH SHOULD BEGIN TO  
DIMINISH AT AROUND 0Z.  
 
THURSDAY NIGHT...VFR AS SHOWERS AND STORMS EXIT, BUT PATCHY FOG  
AND AND LOW CEILINGS POSSIBLE MAINLY ACROSS THE I-95 CORRIDOR  
AND RDG/ABE. WINDS LIGHT AND VARIABLE. LOW CONFIDENCE.  
 
OUTLOOK...  
 
FRIDAY...PERIODS OF MVFR OR LOWER ARE POSSIBLE IN SHOWERS AND  
STORMS.  
 
SATURDAY THROUGH MONDAY...PREVAILING VFR CONDITIONS.  
 
 
   
MARINE  
 
NO MARINE HAZARDS EXPECTED. SOUTHERLY WINDS WITH GUSTS NEAR 20  
KT POSSIBLE.  
 
OUTLOOK...  
 
THURSDAY NIGHT AND THROUGH SUNDAY...NO MARINE HAZARDS EXPECTED.  
 
RIP CURRENTS...  
 
THERE IS A MODERATE RISK FOR THE DEVELOPMENT OF DANGEROUS AND  
LIFE THREATENING RIP CURRENTS AT THE JERSEY SHORE AND A LOW RISK  
AT DELAWARE BEACHES.  
 
FOR FRIDAY, WINDS IN THE MORNING ARE MORE WESTERLY AT 5 TO 10  
MPH BEFORE BECOMING MORE SOUTHWESTERLY IN THE AFTERNOON AT 5 TO  
10 MPH. AN EAST-SOUTHEASTERLY SWELL REMAINS WITH A PERIOD OF  
6-7 SECONDS WITH BREAKING WAVES AROUND 2-3 FEET. AS A RESULT,  
THERE IS A MODERATE RISK FOR THE DEVELOPMENT OF DANGEROUS AND  
LIFE THREATENING RIP CURRENTS AT THE JERSEY SHORE AND A LOW RISK  
AT DELAWARE BEACHES.  
 
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI  
 
 
   
PHI WATCHES/WARNINGS/ADVISORIES  
 
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ060>062-070-071-  
101>106.  
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012>015-  
017>020-022-025>027.  
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.  
MD...NONE.  
MARINE...NONE.  
 
 
 
 
 
DISCUSSION...WFO PHI  
AVIATION...WFO PHI  
MARINE...WFO PHI  
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