104  
FXUS61 KPHI 050056  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
856 PM EDT MON AUG 4 2025  
   
SYNOPSIS
 
 
HIGH PRESSURE WEAKENS TONIGHT INTO TUESDAY AS ANOTHER HIGH PRESSURE  
AREA BUILDS IN TO OUR NORTH AND NORTHEAST THROUGH THE END OF THE  
WEEK. THIS HIGH THEN BEGINS TO SHIFT OFFSHORE OVER THE WEEKEND AND  
INTO EARLY NEXT WEEK, ALLOWING SOUTHERLY FLOW TO BRING BACK THE HEAT  
AND HUMIDITY INTO THE REGION ALONG WITH MORE UNSETTLED WEATHER.  
 

 
   
NEAR TERM /THROUGH TUESDAY/
 
 
DRY AND PLEASANT MID SUMMER CONDITIONS CONTINUING WITH A SLIGHT  
UPTICK IN TEMPERATURES AND HUMIDITY THROUGH TUESDAY.  
 
SHORTWAVE RIDGING WILL BUILD OVER THE REGION INTO TONIGHT,  
WHICH A SHORTWAVE TROUGH BEGINNING TO APPROACH BY LATE TUESDAY.  
AT THE SURFACE, STRONG AND EXPANSIVE HIGH PRESSURE WILL REMAIN  
TO OUR NORTH AND NORTHEAST THROUGH TUESDAY. THIS WILL CONTINUE  
TO SUPPORT AN ONSHORE FLOW REGIME AT THE SURFACE.  
 
CLEAR SKIES ACROSS THE AREA WITH SOME CI SHIFTING AWAY TO THE NORTH  
WHILE ANOTHER AREA APPROACHES FROM THE SOUTHWEST. TEMPERATURES WILL  
FALL WELL INTO THE 60S TONIGHT. ONSHORE FLOW HAS LED TO SLIGHTLY  
HIGHER DEWPOINTS COMPARED TO PREVIOUS DAYS, AND AIRMASS MODIFICATION  
HAS ALLOWED FOR A SLIGHT INCREASE IN TEMPERATURES ACROSS THE BOARD  
AS WELL. SO WHILE NOT AS COOL AS PREVIOUS NIGHTS, STILL BELOW NORMAL  
TEMPERATURES EXPECTED TONIGHT. GIVEN THE HIGHER HUMIDITY, SOME PATCHY  
FOG IS POSSIBLE.  
 
FOR TUESDAY, THE EASTERLY FLOW WILL CONTINUE WITH SIMILAR CONDITIONS  
TO TODAY. HIGHS MAINLY IN THE MID TO UPPER 80S (NEAR 80 DEGREES FOR  
THE HIGHER ELEVATIONS AND COASTS). WITH THE SHORTWAVE TROUGH APPROACHING  
FROM THE WEST, WE'LL SEE AN INCREASE IN CIRRUS COVERAGE.  
 

 
   
SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/
 
 
SURFACE HIGH WILL BEGIN TO STRENGTHEN OVER QUEBEC AND NORTHERN  
NEW ENGLAND TUESDAY NIGHT INTO WEDNESDAY, HELPING REINTRODUCE  
EAST TO NORTHEAST FLOW ACROSS THE REGION. THIS WILL HELP KEEP  
SKIES A BIT CLOUDY, WHICH WILL KEEP TEMPERATURES A BIT WARMER AT  
NIGHT, BUT COOLER DURING THE DAY. LOWS TUESDAY NIGHT WILL BE IN  
THE MID 60S TO AROUND 70. HIGHS ON WEDNESDAY WILL FALL BACK  
INTO THE LOW TO MID 80S, THOUGH DEW POINTS WILL INCREASE A TAD  
WITH ONSHORE FLOW, INCHING BACK INTO THE MID 60S. GUIDANCE  
SUGGEST A FEW LIGHT SHOWERS MAY TRY TO DEVELOP INLAND WITH A  
WEAK SURFACE TROUGH DEVELOPING, BUT PROBABILITIES REMAIN RATHER  
LOW, THEREFORE MOST LOCATIONS MAY REMAIN MOSTLY DRY. COOL  
ONSHORE FLOW WILL ALLOW TEMPS WEDNESDAY NIGHT TO FALL INTO THE  
60S.  
 

 
   
LONG TERM /THURSDAY THROUGH MONDAY/
 
 
HIGH PRESSURE TO OUR NORTH WILL BE SLOW TO MOVE THROUGH THE  
WEEKEND, KEEPING TEMPERATURES ON THE COOLER SIDE FOR A FEW MORE  
DAYS. HIGHS ON THURSDAY WILL BE IN THE UPPER 70S TO LOW 80S WITH  
PARTLY TO MOSTLY CLOUDY SKIES. HIGH PRESSURE WILL SHIFT  
SLIGHTLY SOUTH AND EAST, CLOSER TOWARDS THE SOUTHERN NEW ENGLAND  
COAST, PROVIDING US WITH BETTER OVERALL SUBSIDENCE AS A RESULT.  
MOSTLY SUNNY SKIES ARE EXPECTED WITH TEMPERATURES SLIGHTLY  
WARMING INTO THE LOW TO MID 80S FRIDAY AFTERNOON. A FEW ISOLATED  
SHOWERS CANNOT BE RULED OUT WITH CONSENSUS GUIDANCE SHOWING  
SOME PROBABILITIES ACROSS THE SOUTHERN DELMARVA, BUT MOST  
LOCATIONS SHOULD REMAIN DRY BOTH DAYS.  
 
INTO THE WEEKEND, HIGH PRESSURE WILL CONTINUE TO SHIFT SOUTH  
AND EAST, MOVING FAR OFFSHORE INTO THE ATLANTIC BY EARLY NEXT  
WEEK. THIS WILL BRING SOUTHERLY FLOW BACK INTO THE REGION,  
RESULTING IN GRADUALLY WARMING TEMPERATURES AND HUMIDITY  
CREEPING BACK UP. THIS WILL ALSO HELP OPEN THE DOOR TO MORE  
UNSETTLED WEATHER COME SUNDAY AND MONDAY. GLOBAL GUIDANCE IS  
HINTING AT A POSSIBLE LOW ACROSS THE SOUTHEAST CREEPING  
NORTHWARD, BUT THERE REMAINS ABUNDANT UNCERTAINTY WITH THE  
TIMING, PLACEMENT, AND OVERALL EVOLUTION WITH THIS SYSTEM.  
 

 
   
AVIATION /01Z TUESDAY THROUGH SATURDAY/
 
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
TONIGHT...VFR. WINDS BECOMING LIGHT AND VARIABLE TO CALM BY  
03-06Z. HIGH CONFIDENCE.  
 
TUESDAY...VFR. EAST TO SOUTHEAST WINDS INCREASING TO 5-10 KTS.  
HIGH CONFIDENCE.  
 
OUTLOOK...  
 
TUESDAY NIGHT THROUGH THURSDAY NIGHT...MOSTLY VFR. SOME RISK OF  
FOG AND LOW STRATUS POSSIBLE AT NIGHT.  
 
FRIDAY AND SATURDAY...VFR LIKELY.  
 

 
   
MARINE
 
 
NO MARINE HAZARDS EXPECTED THROUGH TUESDAY. WINDS 10 KTS OR  
LESS, AND SEAS 3-4 FEET.  
 
OUTLOOK...  
 
TUESDAY NIGHT...THE CONDITIONS ARE ANTICIPATED TO BE BELOW  
SMALL CRAFT ADVISORY CRITERIA.  
 
WEDNESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORY CONDITIONS  
POSSIBLE ACROSS OUR OCEAN ZONES, MAINLY DUE TO 5 FOOT SEAS.  
 
SATURDAY...CONDITIONS ARE ANTICIPATED TO BE BELOW SMALL CRAFT  
ADVISORY CRITERIA.  
 
RIP CURRENTS...  
 
FOR TUESDAY, LIGHT NORTHEAST WINDS IN THE MORNING WILL TURN EAST  
AT AROUND 10 MPH IN THE AFTERNOON. AN EASTERLY SWELL OF 3 TO 4  
FEET AROUND 7 TO 8 SECONDS WILL RESULT IN BREAKING WAVES OF 2 TO  
3 FEET AT ALL BEACHES. AS A RESULT, THERE IS A MODERATE RISK  
FOR THE DEVELOPMENT OF DANGEROUS AND LIFE THREATENING RIP  
CURRENT FOR BOTH THE JERSEY SHORE AND DELAWARE BEACHES.  
 
FOR WEDNESDAY, EASTERLY WINDS WILL INCREASE TO 10 TO 20 MPH.  
THERE WILL BE AN EASTERLY SWELL OF 3 TO 4 FEET OF 8 TO 9 SECONDS  
WITH BREAKING WAVES OF 2 TO 3 FEET. THIS WILL GENERALLY RESULT  
IN A MODERATE RISK FOR THE DEVELOPMENT OF DANGEROUS AND LIFE  
THREATENING RIP CURRENTS AT THE JERSEY SHORE AND AT DELAWARE  
BEACHES. IF WINDS ARE A BIT STRONGER, THERE IS THE POTENTIAL FOR  
A HIGH RISK AT THE JERSEY SHORE.  
 
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI  
 

 
   
PHI WATCHES/WARNINGS/ADVISORIES
 
 
PA...AIR QUALITY ALERT FROM MIDNIGHT TONIGHT TO MIDNIGHT EDT  
TUESDAY NIGHT FOR PAZ054-055-060>062.  
AIR QUALITY ALERT UNTIL MIDNIGHT EDT TUESDAY NIGHT FOR PAZ070-  
071-101>106.  
NJ...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR NJZ012>019-  
021.  
DE...NONE.  
MD...NONE.  
MARINE...NONE.  
 

 
 

 
 
SYNOPSIS...MJL  
NEAR TERM...STAARMANN/PO  
SHORT TERM...MJL  
LONG TERM...MJL  
AVIATION...MJL/STAARMANN/PO  
MARINE...MJL/MPS/STAARMANN  
 
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