233  
FXUS61 KPHI 090724  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
324 AM EDT WED JUL 9 2025  
   
SYNOPSIS  
 
A SLOW MOVING FRONTAL BOUNDARY WILL WAFFLE ACROSS THE MID-  
ATLANTIC THROUGH LATE WEEK AS ADDITIONAL DISTURBANCES MOVE  
THROUGH. BERMUDA HIGH PRESSURE WILL BE IN PLACE THROUGH THE  
WEEKEND, EVENTUALLY BREAKING DOWN FOR THE START OF THE NEW WORK  
WEEK. SEVERAL DISTURBANCES WILL PASS THROUGH OVER THE WEEKEND AS  
WELL.  
 
 
   
NEAR TERM /THROUGH TONIGHT/  
 
A WEAK, DIFFUSE FRONTAL BOUNDARY CONTINUES TO SIT OVER THE MID  
ATLANTIC BUT THE STORMS FROM EARLIER HAVE ENDED. IN IT'S WAKE IT  
WILL CONTINUE TO BE A WARM, MUGGY OVERNIGHT PERIOD WITH CHANCES FOR  
A FEW LINGERING SHOWERS, MAINLY NEAR AND SOUTH OF THE URBAN  
CORRIDOR. ALSO EXPECT SOME PATCHY FOG AND LOW STRATUS AROUND.  
 
WEDNESDAY WILL VIRTUALLY BE A RINSE AND REPEAT KIND OF DAY IN TERMS  
OF THE OVERALL FORECAST, EXCEPT THE FRONTAL BOUNDARY WILL HAVE MADE  
ITS WAY CLOSER TO THE AREA, SUPPRESSING THE OVERALL THREAT OF  
CONVECTION A BIT FURTHER SOUTH. EXPECTING PARTLY CLOUDY SKIES IN THE  
MORNING TO GIVE WAY TO MOSTLY CLOUDY SKIES COME THE AFTERNOON. WITH  
THE TROPICAL AND DEEP MOISTURE AIRMASS PERSISTING IN ADDITION TO THE  
NEARBY FRONTAL BOUNDARY, YET ANOTHER ROUND OF SHOWERS AND  
THUNDERSTORMS WILL DEVELOP AROUND LATE AFTERNOON ON WEDNESDAY.  
GREATEST THREAT WILL BE FROM PHILADELPHIA ON SOUTH, WHERE BETTER  
ATMOSPHERIC PARAMETERS OVERLAP WITH ONE ANOTHER, SO SPC HAS A SLIGHT  
RISK IN THOSE AREAS, WITH A MARGINAL RISK REMAINING ELSEWHERE.  
SIMILARLY, WPC HAS KEPT A SLIGHT RISK FOR EXCESSIVE RAINFALL FOR  
MOST OF THE AREA ON WEDNESDAY AS LITTLE CHANGE IN THE OVERALL  
ATMOSPHERIC ENVIRONMENT IS EXPECTED. A NEW FLOOD WATCH FOR FLASH  
FLOODING IS IN EFFECT THAT BASICALLY INCLUDES ALL AREAS FROM THE I-  
78 CORRIDOR SOUTHWARD. COMPARED TO TUESDAY, THE TIMING OF THE  
CONVECTION WILL BE A BIT LATER...MAINLY AFTER 5 PM SO WE BEGIN THE  
FLOOD WATCH AT THIS TIME. ALL IN ALL ANOTHER MUGGY AND HUMID DAY IS  
EXPECTED. TEMPERATURES WILL BE A FEW DEGREES COOLER DUE TO MORE  
CLOUD COVER COMPARED TO TODAY WHERE HEAT INDICIES WILL LARGELY  
REMAIN IN THE 90S FOR THE MAJORITY OF THE AREA. SO IT LOOKS LIKE  
WE'LL FALL SHORT OF NEEDING ANY HEAT HEADLINES.  
 
SHOWERS AND STORMS CONTINUE WEDNESDAY EVENING WITH THE SEVERE THREAT  
GRADUALLY DIMINISHING WITH TIME BUT THE FLASH FLOOD THREAT  
PERSISTING AT LEAST THROUGH THE EVENING PERIOD. PWATS WILL REMAIN  
AROUND 2 INCHES MEANING HEAVY DOWNPOURS WILL BE CAPABLE OF PRODUCING  
LOCALLY 2-3 INCHES OF RAIN WITHIN A 1 TO 3 HOUR TIMEFRAME.  
SHOWERS/STORMS ARE LIKELY TO LINGER OVERNIGHT NEAR AND SOUTH OF THE  
URBAN CORRIDOR HOWEVER THE INTENSITY OF THEM AND ASSOCIATED RAINFALL  
RATES SHOULD DIMINISH. THE FLOOD WATCH RUNS UNTIL 2 AM. LOWS BY  
THURSDAY MORNING SHOULD BE MAINLY IN THE UPPER 60S TO LOW 70S.  
 
 
   
SHORT TERM /THURSDAY THROUGH FRIDAY/  
 
A WARM AND HUMID AIRMASS WILL BE OVER THE NORTHEAST AND MID-  
ATLANTIC FOR THE SHORT TERM PERIOD. SURFACE DEW POINTS WILL BE IN  
THE LOW TO MID 70S, ALONG WITH HIGHS GENERALLY IN THE MID 80S. THIS  
WILL YIELD HEAT INDEX VALUES IN THE LOW TO MID 90S. THESE HIGH DEW  
POINTS WILL ALSO KEEP LOW TEMPERATURES AT NIGHT QUITE WARM, AND LOWS  
WILL GENERALLY BE IN THE LOWER 70S.  
 
UNSETTLED WEATHER WILL REMAIN ON TAP AS A FRONTAL BOUNDARY WILL  
HOVER OVER THE AREA. ABUNDANT LOW LEVEL MOISTURE WILL BE IN PLACE  
GIVEN THOSE HIGH DEW POINTS, AND PWATS WILL BE UP TO AND IN EXCESS  
OF 2 INCHES.  
 
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL IMPACT THE AREA  
THURSDAY AFTERNOON AND EVENING AS SHORTWAVE ENERGY APPROACHES FROM  
THE WEST AND PASSES THROUGH THE REGION. GIVEN HOW WARM AND HUMID  
CONDITIONS WILL BE, LOCALLY HEAVY RAIN AND DAMAGING WIND GUSTS ARE  
POSSIBLE ONCE AGAIN. THIS PATTERN WILL REPEAT YET AGAIN ON FRIDAY.  
 
 
   
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/  
 
A FAIRLY TYPICAL SUMMERTIME PATTERN IS ON TAP FOR THE LONG TERM  
PERIOD WITH WARM AND VERY HUMID CONDITIONS. SURFACE DEW POINTS WILL  
GENERALLY BE IN THE LOW TO MID 70S THOUGH IT IS POSSIBLE THAT DURING  
THE PEAK HEATING OF THE DAY DEW POINTS DROP BY A FEW DEGREES DUE TO  
MIXING. HIGHS WILL GENERALLY BE IN THE MID TO UPPER 80S, POSSIBLY  
AROUND 90 IN SOME SPOTS. THIS WILL GIVE WAY TO MAX HEAT INDEX VALUES  
GENERALLY IN THE LOW TO MID 90S.  
 
A SERIES OF DISTURBANCES WILL PASS THROUGH THE REGION FROM TIME TO  
TIME, BUT CONFIDENCE IN TIMING AND PLACEMENT IS LOW. WILL GENERALLY  
FOLLOW THE NBM AND GO WITH 30 TO 50 PERCENT POPS FOR MOST OF THIS  
TIME, THOUGH THE NBM IS INDICATING 60 PERCENT POPS FOR THE SOUTHERN  
POCONOS, LEHIGH VALLEY, AND BERKS COUNTY ON SUNDAY DUE TO A STRONGER  
SYSTEM POSSIBLY APPROACHING THEN. IMPORTANT TO NOTE THAT ANY SHOWERS  
AND THUNDERSTORMS WILL MOSTLY BE IN THE AFTERNOON AND EVENING HOURS  
AND THERE ARE NOT MANY FACTORS INDICATING PRECIPITATION WOULD BE  
WIDESPREAD AND ORGANIZED AT THIS TIME.  
 
 
   
AVIATION /08Z WEDNESDAY THROUGH SUNDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
REST OF OVERNIGHT...THERE WILL CONTINUE TO BE SOME FLUCTUATION  
IN CONDITIONS WITH LOW MVFR TO IFR CIGS AT TIMES DUE TO LOW  
STRATUS...MAINLY FOR RDG, ABE, TTN, AND PNE. SOME PATCHY FOG  
WILL CONTINUE TO BE AROUND AS WELL AND COULD AFFECT TAF SITES.  
SOUTHWEST WINDS AROUND 3-6 KT. LOW CONFIDENCE.  
 
WEDNESDAY...PRIMARILY VFR WITH ANOTHER ROUND OF SHOWERS AND  
THUNDERSTORMS DEVELOPING BY LATE AFTERNOON. ANY SHOWERS AND  
STORMS MAY CAUSE LOCALIZED AREAS OF VSBY/CIG RESTRICTIONS.  
SOUTHWEST WINDS AROUND 5-10 KT. MODERATE CONFIDENCE.  
 
WEDNESDAY NIGHT...SHOWERS AND STORMS CONTINUING WITH ASSOCIATED  
RESTRICTIONS TO AT LEAST MVFR AT AT TIMES. WINDS LIGHT AND  
VARIABLE (AROUND 5 KNOTS OR LESS) BUT GENERALLY FAVORING A S TO  
SW DIRECTION.  
 
OUTLOOK...  
 
THURSDAY THROUGH SUNDAY...OVERALL, VFR CONDITIONS. HOWEVER,  
AFTERNOON AND EVENING SHRA/TSRA MAY RESULT IN BRIEF SUB-VFR  
CONDITIONS IF A GIVEN STORM PASSES OVER A TERMINAL. SUB- VFR  
CONDITIONS POSSIBLE AT NIGHT DUE TO FOG AND LOW CLOUDS, BUT  
CONFIDENCE LOW ON TIMING AND PLACEMENT.  
 
 
   
MARINE  
 
NO MARINE HEADLINES ARE IN EFFECT THROUGH WEDNESDAY NIGHT. SOME  
SHOWERS ARE LINGERING EARLY THIS MORNING OVER OUR SOUTHERN  
WATERS WITH ANOTHER ROUND OF SHOWERS/STORMS EXPECTED LATE  
WEDNESDAY INTO WEDNESDAY NIGHT. THESE COULD ONCE AGAIN BRING  
LOCALIZED WIND GUSTS IN EXCESS OF 34 KT.  
 
OUTLOOK...  
 
THURSDAY THROUGH SUNDAY...SUB-SCA CONDITIONS FOR THIS PERIOD.  
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS POSSIBLE EACH  
DAY. VSBY RESTRICTIONS POSSIBLE FROM TIME TO TIME, ESPECIALLY AT  
NIGHT.  
 
RIP CURRENTS...  
 
FOR WEDNESDAY, A SOUTH/SOUTHWEST SHORE PARALLEL WIND OF AROUND  
10-20 MPH AND BREAKING WAVES OF AROUND 2-3 FEET WILL RESULT IN  
A MODERATE RISK FOR THE JERSEY SHORE. WITH WIND DIRECTION MAINLY  
OFFSHORE ALONG THE DELAWARE BEACHES, A LOW RISK FOR RIP  
CURRENTS IS IN PLACE. SIMILAR CONDITIONS ARE EXPECTED FOR  
THURSDAY SO WE'LL CONTINUE WITH A MODERATE RISK FOR THE JERSEY  
SHORE AND A LOW RISK OF RIP CURRENTS FOR THE DELAWARE BEACHES.  
 
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  
 
 
   
HYDROLOGY  
 
A FLOOD WATCH WAS ISSUED FOR AREAS ALONG AND SOUTH OF I-78 FOR  
WEDNESDAY. RAINFALL OF AROUND 0.5 INCHES TO UPWARDS OF 3 TO 4  
INCHES FELL ACROSS THE WATCH AREA. THIS RESULTS IN A SATURATED  
SURFACE AND LOW FFG VALUES WITHIN THE WATCH AREA. IT WILL NOT  
TAKE MUCH TO CAUSE FURTHER FLOODING ISSUES, ESPECIALLY IN SE PA,  
WHERE WIDESPREAD FLOODING WAS REPORTED TODAY. RAINFALL RATES OF  
2 TO 3 INCHES PER HOUR ARE POSSIBLE WITH THUNDERSTORMS ROLLING  
THROUGH WEDNESDAY EVENING.  
 
 
   
PHI WATCHES/WARNINGS/ADVISORIES  
 
PA...FLOOD WATCH FROM THIS AFTERNOON THROUGH LATE TONIGHT FOR  
PAZ060>062-070-071-101>106.  
NJ...FLOOD WATCH FROM THIS AFTERNOON THROUGH LATE TONIGHT FOR  
NJZ009-010-012>027.  
DE...FLOOD WATCH FROM THIS AFTERNOON THROUGH LATE TONIGHT FOR  
DEZ001>004.  
MD...FLOOD WATCH FROM THIS AFTERNOON THROUGH LATE TONIGHT FOR  
MDZ012-015-019-020.  
MARINE...NONE.  
 
 
 
 
 
SYNOPSIS...FITZSIMMONS/MPS  
NEAR TERM...DESILVA/FITZSIMMONS/HOEFLICH/STAARMANN  
SHORT TERM...FITZSIMMONS/MPS  
LONG TERM...FITZSIMMONS/MPS  
AVIATION...DESILVA/FITZSIMMONS/MPS  
MARINE...DESILVA/FITZSIMMONS/MPS  
HYDROLOGY...  
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