979  
FXUS61 KPHI 051051  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
651 AM EDT SAT JUL 5 2025  
   
SYNOPSIS  
 
DRY HIGH PRESSURE WILL WILL REMAIN IN CONTROL THROUGH THE  
WEEKEND, RESULTING IN SEASONABLE TEMPERATURES AND TRANQUIL  
WEATHER CONDITIONS. WARMER, MORE HUMID, AND UNSETTLED CONDITIONS  
WILL RETURN INTO NEXT WEEK, WITH DAILY CHANCES FOR SHOWERS AND  
THUNDERSTORMS.  
 
 
   
NEAR TERM /THROUGH TONIGHT/  
 
LARGE SCALE SUBSIDENCE AND HIGH PRESSURE WILL LEAD TO ANOTHER  
DAY OF MOSTLY CLEAR SKIES AND QUIET SENSIBLE WEATHER FOR THE  
REGION. HIGHS TODAY WILL START TO WARM AS SOUTHERLY FLOW  
INCREASES. THE SOUTHERLY RETURN FLOW WILL ALSO START TO INCREASE  
HUMIDITY FOR THE REGION AS DEWPOINTS START TO INCREASE FROM THE  
UPPER 50S TOWARDS THE LOW 60S. OVERALL AS THE PREVIOUS SHIFTS  
MENTIONED, ITS GOING TO BE A PLEASANT SUMMER DAY.  
 
HEADING INTO THE OVERNIGHT HOURS, TEMPS WILL FALL TOWARDS NEAR  
NORMAL CONDITIONS WITH LOWS SETTLING INTO THE MID 60S UNDER  
MOSTLY CLEAR TO PARTLY CLOUDY SKIES. THE INCREASE IN HUMIDITY  
CONTINUES WITH DEW POINTS REMAINING IN THE LOW 60S OVERNIGHT SO  
SOME PATCHY GROUND FOG MAY BE POSSIBLE IN AREAS THAT SEE THE  
WINDS DECOUPLE OVERNIGHT.  
 
 
   
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/  
 
DRY AND SEASONABLE CONDITIONS EXPECTED TO CLOSE OUT THE HOLIDAY  
WEEKEND, THEN TURNING UNSETTLED AND STORMY AGAIN WITH  
INCREASING HUMIDITY INTO EARLY NEXT WEEK.  
 
BROAD RIDGING ACROSS THE REGION WILL BEGIN TO RETREAT OFFSHORE  
LATE SUNDAY INTO MONDAY AS SHORTWAVE TROUGHING DEVELOPS ACROSS  
THE UPPER MIDWEST AND GREAT LAKES REGIONS. AT THE SURFACE, HIGH  
PRESSURE WILL BE LOCATED OFFSHORE WITH RETURN FLOW DEVELOPING ON  
SUNDAY THROUGH MONDAY AS TROPICAL CYCLONE REMNANTS DISSIPATE  
ACROSS THE CAROLINAS. THIS SETUP WILL RESULT IN A SLIGHT WARMING  
TREND IN TEMPERATURES, AND A MORE SIGNIFICANT INCREASE IN  
DEWPOINTS AND HUMIDITY ESPECIALLY BY MONDAY.  
 
FOR SUNDAY, HIGH PRESSURE WILL BE LOCATED OFFSHORE, RESULTING  
IN SOME RETURN FLOW AND THUS A MORE SENSIBLE INCREASE IN  
TEMPERATURES AND HUMIDITY LEVELS COMPARED TO THE PREVIOUS DAYS.  
HIGHS SUNDAY IN THE UPPER 80S TO LOW 90S. LOWS MOSTLY IN THE 70  
TO 75 DEGREE RANGE IN MOST AREAS AS WE BEGIN EXPERIENCING MUGGY  
NIGHTS AGAIN. SUNDAY SHOULD BE LARGELY DRY, HOWEVER THE  
DIMINISHING SUBSIDENCE AND INCREASING INFLUENCE FROM THE  
WEAKENING TROPICAL CYCLONE OVER THE CAROLINAS COULD RESULT IN AN  
ISOLATED THUNDERSTORM ACROSS DELMARVA.  
 
BY MONDAY, AN UPPER JET STREAK TO OUR NORTHEAST WILL PLACE OUR  
REGION IN A WEAK DIFFLUENCE REGIME ALOFT. THUS WITH THE  
INCREASING HUMIDITY AND DIURNALLY DRIVEN INSTABILITY, WE SHOULD  
EXPERIENCE SCATTERED CONVECTION DEVELOPING BY MIDDAY. THE  
CONVECTIVE ENVIRONMENT WON'T BE PARTICULARLY FAVORABLE FOR  
SEVERE THUNDERSTORMS, HOWEVER A FEW ISOLATED SEVERE STORMS  
CANNOT BE RULED OUT. VERTICAL SHEAR IS RELATIVELY WEAK, ONLY  
AROUND 10-20 KTS OR SO, AND THE INSTABILITY PROFILE IS TALL,  
SKINNY CAPE ON THE ORDER OF 2000 J/KG. PWATS WILL BE ON THE RISE  
TOO, PERHAPS AS MUCH AS 2.0". SO A DECIDEDLY TROPICAL  
ENVIRONMENT WITH LIGHT FLOW COULD RESULT IN SOME LOCALLY HEAVY  
RAINFALL AMOUNTS AND LOCALIZED FLOOD THREAT IN ADDITION TO THE  
WATER LOADED DOWNDRAFTS AND LOCALIZED SEVERE THREAT.  
 
HIGH TEMPERATURES MONDAY WILL BE SIMILAR TO SUNDAY IN THE UPPER  
80S TO LOW 90S, HOWEVER DEWPOINTS AND HUMIDITY WILL BE  
NOTICEABLY HIGHER COMPARED TO SUNDAY. THIS WILL RESULT IN HEAT  
INDICES IN THE MID TO UPPER 90S IN MOST INLAND AREAS. CLOUD  
COVER WILL ALSO BE NOTICEABLY INCREASED COMPARED TO THE WEEKEND.  
WARM AND MUGGY CONDITIONS REMAINING AT NIGHT WITH LOWS IN THE  
70 TO 75 DEGREE RANGE.  
 
 
   
LONG TERM /TUESDAY THROUGH FRIDAY/  
 
UNSETTLED CONDITIONS EXPECTED FOR THE REMAINDER OF THE UPCOMING  
WEEK. DAILY CHANCES OF SHOWERS AND THUNDERSTORMS WITH THREATS  
FOR LOCALIZED SEVERE THUNDERSTORMS AND FLOODING, ALONG WITH  
VERY WARM AND HUMID CONDITIONS.  
 
SOUTHWESTERLY RETURN FLOW WILL CONTINUE THROUGH TUESDAY AS A  
SHORTWAVE TROUGH APPROACHES FROM THE GREAT LAKES REGION. THE  
SHORTWAVE TROUGH WILL PASS OFFSHORE INTO WEDNESDAY, WITH ANOTHER  
APPROACHES THURSDAY OR FRIDAY. THIS SHOULD RESULT IN THE  
GREATEST CHANCES FOR SHOWERS AND STORMS OCCURRING ON TUESDAY FOR  
THE FIRST HALF OF THE WEEK, AND AGAIN THURSDAY OR FRIDAY.  
 
TUESDAY'S CONVECTIVE ENVIRONMENT WILL BE SIMILAR TO MONDAY'S,  
ALTHOUGH COVERAGE OF CONVECTION IS ANTICIPATED TO BE GREATER  
THAN MONDAY GIVEN THE FORCING ALOFT. PWATS IN THE 2.0-2.3"  
RANGE; TALL, SKINNY CAPE ON THE ORDER OF 2000-3000 J/KG; AND  
RELATIVELY LOW UNIDIRECTIONAL SHEAR NEAR 15-20 KTS COULD SUPPORT  
TRAINING CONVECTION WHERE ANY SURFACE BOUNDARIES ARE IN PLACE.  
SO AGAIN, A MARGINAL SEVERE ENVIRONMENT, BUT PERHAPS MORE  
CONCERNING IS THE HEAVY RAINFALL AND FLOODING THREAT THIS SETUP  
WILL PRESENT. WE'LL CONTINUE TO MONITOR THIS POTENTIAL CLOSELY  
IN THE COMING DAYS.  
 
WEDNESDAY SHOULD SEE LESS COVERAGE OF CONVECTION GIVEN THE  
SHORTWAVE TROUGH PUSHING OFFSHORE, BUT SOME ISOLATED STORMS WILL  
CERTAINLY REMAIN POSSIBLE. THE NEXT SYSTEM APPROACHING FROM THE  
WEST BY THURSDAY WILL THEN YIELD GREATER CHANCES FOR STORMS TO  
CLOSE OUT THE WEEK, BUT DETAILS ON THIS REMAIN UNCLEAR AT THE  
MOMENT.  
 
EXPECT TEMPERATURES TO REMAIN NEAR TO SLIGHTLY ABOVE NORMAL  
WITH HIGH HUMIDITY LEVELS THROUGH MUCH OF THE WEEK (GREATEST ON  
TUESDAY). HIGHS IN THE MID 80S TO LOW 90S AND LOWS IN THE MID  
60S TO MID 70S. LOW PRESSURE DEVELOPING TO OUR WEST WITH THE  
LATE WEEK SHORTWAVE SHOULD RESULT IN SOME ONSHORE FLOW LATE IN  
THE WEEK, WHICH SHOULD TEND TO MODERATE TEMPERATURES A BIT. HEAT  
INDICES COULD APPROACH 100 DEGREES ACROSS THE SOUTHERN HALF OF  
THE AREA ON TUESDAY, HOWEVER THE INCREASED CLOUD COVER AND  
SCATTERED CONVECTION SHOULD TEND TO KEEP THIS THREAT SUPPRESSED  
SOME.  
 
 
   
AVIATION /12Z SATURDAY THROUGH WEDNESDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
TODAY...VFR. LIGHT AND VARIABLE WIND BECOMING SOUTH-SOUTHWEST  
AND INCREASING TO 5-10 KT DURING THE AFTERNOON. HIGH CONFIDENCE.  
 
TONIGHT...VFR. LIGHT SOUTHWESTERLY FLOW. NO SIGNIFICANT  
WEATHER.  
 
OUTLOOK...  
 
SUNDAY...VFR. NO SIGNIFICANT WEATHER.  
 
MONDAY THROUGH WEDNESDAY...PREVAILING VFR WITH DAILY CHANCES  
FOR THUNDERSTORMS. AREAS OF FOG POSSIBLE AT NIGHT.  
 
 
   
MARINE  
 
NO MARINE HEADLINES ARE IN EFFECT THROUGH TONIGHT. WINDS MAINLY  
OUT OF THE SOUTH-SOUTHWEST AROUND 5-10 KNOTS THROUGH THE  
PERIOD, BUT MAY BE LIGHT AND VARIABLE AT TIMES TONIGHT. SEAS OF  
2-3 FEET. FAIR WEATHER.  
 
OUTLOOK...  
 
SUNDAY...NO MARINE HAZARDS EXPECTED.  
 
MONDAY THROUGH WEDNESDAY...DAILY CHANCES OF SHOWERS AND  
THUNDERSTORMS, OTHERWISE FAIR WEATHER.  
 
RIP CURRENTS...  
 
FOR TODAY, LIGHT WINDS IN THE MORNING WILL BECOME SOUTH-  
SOUTHEASTERLY AROUND 10 MPH IN THE AFTERNOON. BREAKING WAVE  
HEIGHTS OF 1-2 FEET WITH A PRIMARY SE SWELL AROUND 2 FEET AND A  
6-8 SECOND PERIOD. THIS SHOULD RESULT IN A LOW RISK FOR  
DANGEROUS RIP CURRENTS FOR ALL BEACHES.  
 
FOR SUNDAY, SOUTHWESTERLY WINDS AROUND 5 MPH IN THE MORNING  
WILL BECOME SOUTHERLY IN THE AFTERNOON AND INCREASE TO 10-15  
MPH. BREAKING WAVE HEIGHTS OF 1-3 FEET WITH A PRIMARY SE SWELL  
AROUND 2 FEET AND A 6-8 SECOND PERIOD. GUIDANCE IS HINTING AT  
SOME LONGER PERIOD SWELLS POTENTIALLY BECOMING DOMINATE WITH  
SWELLS RANGING FROM 10-14 SECONDS. THIS WOULD INCREASE THE RIP  
CURRENT RISK TO AT LEAST MODERATE HOWEVER GIVEN THE SWELLS  
SHOULD BE LESS THAN 3 FEET AND BREAKING WAVES ARE SMALL, WILL  
CONTINUE A LOW RISK FOR DANGEROUS RIP CURRENTS FOR ALL BEACHES  
AT THIS TIME.  
 
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...NONE.  
NJ...NONE.  
DE...NONE.  
MD...NONE.  
MARINE...NONE.  
 
 
 
 
 
SYNOPSIS...STAARMANN  
NEAR TERM...DEAL  
SHORT TERM...STAARMANN  
LONG TERM...STAARMANN  
AVIATION...DEAL/STAARMANN  
MARINE...DEAL/STAARMANN  
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