797
FXUS61 KPHI 161759
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
159 PM EDT TUE SEP 16 2025
SYNOPSIS
A SURFACE LOW LOCATED NEAR THE MID-ATLANTIC COAST TODAY WILL
TRACK SLOWLY NORTHEASTWARD TOWARDS THE AREA THROUGH WEDNESDAY
NIGHT, BRINING UNSETTLED WEATHER. THURSDAY AND BEYOND, THE LOW
IS EXPECTED TO TRACK NORTHEAST AWAY FROM THE AREA WHILE
WEAKENING. A COLD FRONT WILL MOVE THROUGH THE AREA ON FRIDAY,
WITH STRONG HIGH PRESSURE IN ITS WAKE REMAINING IN CONTROL
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
NEAR TERM /THROUGH WEDNESDAY/
HIGH PRESSURE CENTERED OVER THE PROVINCE OF QUEBEC NORTH OF NEW
YORK STATE WILL SLIDE TOWARDS THE CANADIAN MARITIMES TONIGHT
AND THEN WILL MOVE OFFSHORE AND OVER THE WESTERN ATLANTIC OCEAN
ON WEDNESDAY. MEANWHILE, LOW PRESSURE OFF THE VIRGINIA/NORTH
CAROLINA COAST WILL SLOWLY RETROGRADE INLAND TONIGHT THROUGH
WEDNESDAY, WHERE IT WILL MEANDER.
THE FIRST WAVES OF SHOWERS IMPACTED DELMARVA, SOUTHERN NEW
JERSEY, AND PORTIONS OF THE DELAWARE VALLEY, AND THESE INITIAL
WAVES WILL WIND DOWN DURING THE LATE AFTERNOON HOURS. THERE
SHOULD BE A LULL THROUGH THIS EVENING, AND THEN WAVES OF SHOWERS
WILL RAMP UP AGAIN TONIGHT THROUGH WEDNESDAY.
THE HIGHEST QPF WILL BE OVER DELMARVA AND SOUTHERN NEW JERSEY
UP TO THE I-95 CORRIDOR, WHERE 1/2 INCH TO 1 INCH OF RAIN WILL
FALL DURING THIS TIME. NORTH AND WEST OF THE I-95 CORRIDOR, UP
TO 1/4 INCH OF RAIN IS EXPECTED.
A TIGHT PRESSURE GRADIENT WILL FORM BETWEEN THE TWO SYSTEMS.
EAST TO NORTH WINDS WILL RANGE FROM 10 TO 20 MPH NORTH AND WEST
OF THE I-95 CORRIDOR, AND FROM 15 TO 25 MPH WITH GUSTS UP TO 35
MPH SOUTH AND EAST OF THE I-95 CORRIDOR, WITH THE STRONGEST
WINDS RIGHT ALONG THE COAST.
SOME SHORTWAVE ENERGY MAY PROVIDE ENOUGH INSTABILITY TO TRIGGER
A COUPLE OF THUNDERSTORMS, SOME OF WHICH COULD RESULT IN
LOCALLY HEAVY DOWNPOURS WITH ENHANCED RAINFALL IN THOSE AREAS,
AND BRIEF WIND GUSTS AS HIGH AS 45 MPH. BEST CHANCES FOR
CONVECTION WILL BE OVER DELMARVA, SOUTHERN NEW JERSEY, AND THE
DELAWARE VALLEY.
LOWS TONIGHT WILL GENERALLY BE IN THE UPPER 50S TO LOW 60S AND
HIGHS ON WEDNESDAY WILL BE IN THE UPPER 60S TO LOW 70S, THOUGH
POSSIBLY AS WARM AS THE MID 70S IN SOUTHERN DELMARVA.
SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/
BY WEDNESDAY NIGHT, THE COASTAL LOW WILL BE WEAKENING
SUBSTANTIALLY TO THE SOUTHWEST OF THE AREA. IT WILL CONTINUE TO
MOVE EAST TO NORTHEAST AWAY FROM THE AREA WHILE WEAKENING INTO
THURSDAY AFTERNOON. LINGERING SHOWERS ARE EXPECTED WEDNESDAY
NIGHT, PRIMARILY ACROSS SOUTHEASTERN PORTIONS OF NJ AND THE
EASTERN DELMARVA. A FEW ISOLATED SHOWERS ARE POSSIBLE ACROSS THE
REST OF THE AREA AS WELL, BUT COVERAGE WILL BE MUCH LESS
WIDESPREAD. WITH LOW CLOUDS AND SHOWERS, LOW TEMPERATURES WILL
GENERALLY BE IN THE LOW 60S. ACROSS THE POCONOS AND INTO FAR
NORTHERN NJ, SOME CLEARING IS POSSIBLE, WHICH WOULD ALLOW
TEMPERATURES TO DROP INTO THE MID-UPPER 50S.
ANY REMAINING SHOWERS WILL DEPART THE AREA BY THURSDAY
AFTERNOON, WITH CLOUD COVER DECREASING FROM NORTHWEST TO
SOUTHEAST THROUGHOUT THE DAY. AFTERNOON HIGHS LOOK TO BE IN THE
MID-UPPER 70S. THURSDAY NIGHT, UNDER PARTLY TO MOSTLY CLEAR
SKIES, SLIGHTLY COOLER TEMPERATURES ARE EXPECTED, RANGING FROM
THE MID-UPPER 50S ACROSS EASTERN PA AND NORTHERN NJ TO THE LOW
60S ACROSS SOUTHEASTERN PA, SOUTHERN NJ, AND THE DELMARVA.
FRIDAY LOOKS TO BE A NICE, WARM DAY ACROSS THE AREA. UNDER
MOSTLY CLEAR SKIES, TEMPERATURES SHOULD RISE INTO THE LOW 80S
FOR MOST LOCATIONS. A COLD FRONT WILL BEGIN TO APPROACH FROM THE
NORTHWEST, AND DEPENDING ON TIMING, IT IS POSSIBLE THAT IT
COULD LIMIT WARMING ACROSS NORTHERN PARTS OF THE AREA IF IT
MOVES IN A LITTLE FASTER THAN CURRENTLY ANTICIPATED. THE COLD
FRONT WILL MOVE THROUGH THE ENTIRE AREA THROUGH FRIDAY NIGHT. NO
PRECIPITATION IS EXPECTED, BUT THIS FRONT WILL USHER IN COOLER
TEMPERATURES. LOWS FRIDAY NIGHT WILL GENERALLY BE IN THE MID-
UPPER 50S, WITH UPPER 40S ACROSS THE POCONOS AND FAR NORTHERN
NJ.
LONG TERM /SATURDAY THROUGH MONDAY/
AFTER THE PASSAGE OF FRIDAY'S COLD FRONT, STRONG HIGH PRESSURE
CENTERED OVER PORTIONS OF ONTARIO, QUEBEC, AND NORTHERN NEW
ENGLAND WILL SHIFT SOUTHEAST INTO THE AREA. THIS WILL LEAD TO
COMFORTABLE TEMPERATURES WITH BENIGN WEATHER THROUGH THE
WEEKEND, WITH A SLOW WARMING TREND. SATURDAY AND SUNDAY SHOULD
FEATURE HIGH TEMPERATURES IN THE LOW-MID 70S AREAWIDE, WITH LOWS
GENERALLY IN THE MID 50S.
MONDAY AND TUESDAY LOOK TO BE SLIGHTLY WARMER, WITH HIGHS IN
THE MID- UPPER 70S AND LOWS IN THE UPPER 50S TO LOWER 60S. LOW
PRESSURE OFF THE EAST COAST WILL APPROACH THE AREA MONDAY INTO
MONDAY NIGHT, THIS WILL LEAD TO SOME INCREASE IN CLOUD COVER AND
PERHAPS A SHOWER OR TWO ALONG THE IMMEDIATE COAST, BUT THAT
SHOULD BE THE EXTENT OF THE IMPACTS.
IT CONTINUES TO LOOK LIKE THE UPPER-PATTERN WILL BECOME
SLIGHTLY MORE UNSETTLED TOWARDS TUESDAY AND BEYOND, BUT FOR NOW
IT LOOKS LIKE ANY MORE ACTIVE WEATHER WILL HOLD OFF UNTIL JUST
BEYOND THE FORECAST TIMEFRAME.
AVIATION /18Z TUESDAY THROUGH SUNDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
REST OF TODAY...GENERALLY VFR, THOUGH BRIEF MVFR OR IFR
CONDITIONS POSSIBLE AT KMIV/KACY IN RA. E-NE WINDS GENERALLY 8
TO 12 KT, THOUGH 10 TO 15 KT WITH GUSTS UP TO 20 KT AT
KMIV/KACY. LOW CONFIDENCE.
TONIGHT...CONDITIONS LOWER TO MVFR/IFR THROUGHOUT IN LOW CLOUDS
AND RAIN, THOUGH CONDITIONS MAY NOT LOWER TO SUB-VFR AT
KRDG/KABE UNTIL AFTER 09Z. E-NE WINDS 5 TO 10 KT AT KRDG/KABE,
AND 10 TO 15 KT WITH GUSTS UP TO 20 KT ELSEWHERE. WINDS 15 TO 20
KT WITH GUSTS UP TO 30 KT POSSIBLE AT KMIV/KACY. A FEW EMBEDDED
THUNDERSTORMS MAY IMPACT KMIV/KACY. LOW CONFIDENCE.
WEDNESDAY...MVFR/IFR IN LOW STRATUS AND RAIN. NE WINDS 10 TO 15
KT WITH GUSTS UP TO 20 KT, THOUGH GUSTS UP TO 25 KT LIKELY AT
KACY. A FEW EMBEDDED THUNDERSTORMS MAY IMPACT KMIV/KACY. LOW
CONFIDENCE.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY...PERIODS OF SUB-VFR
CONDITIONS ARE POSSIBLE IN SCATTERED SHOWERS AND LOW CLOUDS,
ESPECIALLY FOR THE I- 95 TERMINALS SOUTH AND EAST. CONDITIONS
SHOULD IMPROVE THROUGH THURSDAY, BUT LINGERING PERIODS OF SUB-
VFR CONDITIONS CAN'T BE RULED OUT.
THURSDAY NIGHT THROUGH SUNDAY...VFR. NO SIGNIFICANT WEATHER.
MARINE
A COASTAL LOW WILL AFFECT THE WATERS TONIGHT THROUGH AT LEAST
WEDNESDAY.
GALE WARNINGS REMAIN IN EFFECT FOR LOWER DELAWARE BAY UNTIL 6
PM, AND FOR THE COASTAL WATERS FROM GREAT EGG INLET TO FENWICK
ISLAND UNTIL 10 PM TONIGHT. SMALL CRAFT ADVISORIES ARE IN EFFECT
FOR UPPER DELAWARE BAY THROUGH TONIGHT AND FOR THE COASTAL
WATERS FROM GREAT EGG INLET TO SANDY HOOK THROUGH WEDNESDAY.
ONCE THE GALE WARNINGS END, A SCA WILL BE NEEDED FOR THOSE
WATERS THROUGH AT LEAST WEDNESDAY.
EAST TO NORTHEAST WINDS 15 TO 25 KT WITH 35 TO 40 KT GUSTS
WHERE THE GALE WARNINGS ARE IN EFFECT AND GUSTS UP TO 30 KT
ELSEWHERE. SEAS 6 TO 10 FEET WILL SUBSIDE TO 5 TO 8 FEET
TONIGHT, AND THEN TO 3 TO 5 FEET ON WEDNESDAY.
VISIBILITY RESTRICTIONS IN RAIN AND FOG. A FEW EMBEDDED
THUNDERSTORMS MAY AFFECT THE WATERS TONIGHT THROUGH WEDNESDAY.
OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY NIGHT...WINDS AND SEAS ARE
EXPECTED TO HAVE DIMINISHED BELOW SCA CRITERIA BY WEDNESDAY
NIGHT, AND SHOULD REMAIN SO THROUGH FRIDAY NIGHT. NO MARINE
HEADLINES ARE EXPECTED.
SATURDAY THROUGH SATURDAY NIGHT...A PERIOD OF ENHANCED
NORTHERLY WINDS AND ELEVATED SEAS ARE POSSIBLE BEHIND A COLD
FRONT. CURRENTLY, IT APPEARS THAT WINDS SHOULD REMAIN BELOW 25
KT AND SEAS BELOW 5 FEET, BUT THIS WILL NEED TO BE MONITORED AS
IT GETS CLOSER IN TIME.
SUNDAY...NO MARINE HEADLINES EXPECTED. FAIR WEATHER.
RIP CURRENTS...
FOR TODAY, NORTHEAST WINDS FURTHER INCREASE TO AROUND 15 TO 25
MPH WITH BREAKING WAVES INCREASING TO 4 TO 6 FEET WITH A FEW 7
FOOT SEAS POSSIBLE ALONG THE DELAWARE COAST. FURTHERMORE, A
STRONG 9 FOOT 9 SECOND EAST TO EAST-NORTHEAST SWELL WILL
CONTRIBUTE SIGNIFICANTLY. THIS WILL RESULT IN A HIGH RISK FOR
THE DEVELOPMENT OF DANGEROUS RIP CURRENTS.
FOR WEDNESDAY, NORTHEAST WINDS DIMINISH TO AROUND 10 TO 15 MPH
WITH BREAKING WAVES OF 3 TO 5 FEET. THE EAST TO EAST-NORTHEAST
SWELL DOES SUBSIDE TO AROUND 5 TO 7 FEET AT 8 SECONDS, BUT WILL
REMAIN QUITE STRONG. AS A RESULT, A HIGH RISK FOR THE
DEVELOPMENT OF DANGEROUS RIP CURRENTS IS EXPECTED TO CONTINUE.
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI
TIDES/COASTAL FLOODING
A COASTAL LOW OFF THE CAROLINA COASTLINE WILL BRING A PERSISTENT
FETCH OF NORTHEAST WINDS ACROSS THE REGION. THIS IS EXPECTED TO
CAUSE WATER ALONG THE DELAWARE BAY TO BUILD UP ALONG THE
SOUTHERN SIDE ALONG THE TIDAL WATERWAYS ALONG THE DELAWARE
COAST. AS A RESULT, MINOR COASTAL FLOODING IS EXPECTED FOR THE
SHORELINES AND TIDAL WATERWAYS OF KENT AND SUSSEX COUNTY
DELAWARE DURING THE TUESDAY LATE AFTERNOON/EVENING HIGH TIDE
CYCLE.
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...HIGH RISK FOR RIP CURRENTS UNTIL 8 PM EDT THIS EVENING FOR NJZ014-
024>026.
DE...COASTAL FLOOD ADVISORY UNTIL 9 PM EDT THIS EVENING FOR
DEZ002>004.
HIGH RISK FOR RIP CURRENTS UNTIL 8 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ430.
GALE WARNING UNTIL 6 PM EDT THIS EVENING FOR ANZ431.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR ANZ450>452.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR ANZ453>455.
SYNOPSIS...COOPER
NEAR TERM...MPS
SHORT TERM...COOPER
LONG TERM...COOPER
AVIATION...COOPER/MPS
MARINE...COOPER/MPS
TIDES/COASTAL FLOODING...
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page