492
FXUS61 KPHI 301909
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
309 PM EDT THU OCT 30 2025
SYNOPSIS
A STRONG LOW PRESSURE SYSTEM WILL CONTINUE TO TRACK THROUGH THE
REGION INTO TONIGHT. THE SYSTEM WILL TRACK NORTHEASTWARD AWAY
FROM THE AREA FRIDAY, WITH HIGH PRESSURE BUILDING IN THIS
WEEKEND. A COLD FRONT WILL MOVE THROUGH MONDAY NIGHT INTO
TUESDAY. HIGH PRESSURE WILL RETURN THROUGH MID-WEEK, WITH
ANOTHER POTENTIAL STORM SYSTEM APPROACHING THE AREA THURSDAY.
NEAR TERM /THROUGH FRIDAY NIGHT/
LOW PRESSURE LIES OVER EASTERN OHIO AND WESTERN PENNSYLVANIA
AND WILL CONTINUE TO LIFT TO THE NORTH AND EAST. A WEAK LOW MAY
DEVELOP OVER NEW JERSEY THIS EVENING, AND THAT LOW LIFTS
NORTHEAST INTO LONG ISLAND LATE TONIGHT AND INTO FRIDAY MORNING.
A LINE OF SHOWERS PRODUCING HEAVY RAIN IS LIFTING THROUGH NEW
JERSEY, AND THE HEAVIEST OF THIS RAIN SHOULD END IN THE NEXT
COUPLE OF HOURS. LINGERING RAIN WILL OTHERWISE TAPER OFF THROUGH
THIS EVENING. WINDS DIMINISH THIS EVENING, AND TURN TO THE WEST
BEHIND THE DEPARTING LOW. THOUGH 30 TO 35 MPH GUSTS WILL
CONTINUE FOR A COUPLE OF MORE HOURS, IT DOES LOOK LIKE THE WIND
ADVISORY THAT WAS IN EFFECT UNTIL 5 PM FOR PORTIONS OF NORTHEAST
NEW JERSEY CAN BE CANCELLED.
LOW PRESSURE INTENSIFIES OVER EASTERN CANADA AND THE PRESSURE
GRADIENT TIGHTENS BETWEEN THAT LOW AND HIGH PRESSURE BUILDING
INTO THE CENTRAL PLAINS AND MIDWEST. WINDS INCREASE TO 10 TO 20
MPH LATE TONIGHT.
ON FRIDAY, A SURGE OF WINDS AT 850 MB OR SO WILL RANGE FROM 45
TO 50 MPH. WITH SKIES CLEARING OUT AND STRONG MIXING DEVELOPING,
THIS WILL RESULT IN WEST WINDS 20 TO 30 MPH WITH 40 TO 50 MPH
GUSTS. WILL GO AHEAD AND ISSUE A WIND ADVISORY FOR SOUTHEAST
PENNSYLVANIA, NEW JERSEY, AND DELAWARE FOR FRIDAY AND FRIDAY
EVENING.
WINDS DIMINISH FRIDAY NIGHT.
LOWS IN THE MID AND UPPER 40S TONIGHT. COLD AIR ADVECTION WILL
BE UNDERWAY ON FRIDAY, AND HIGHS WILL BE SOME 10 DEGREES COOLER
COMPARED TO TODAY, TOPPING OFF IN THE MID AND UPPER 50S. LOWS IN
THE LOW TO MID 40S FRIDAY NIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
ENHANCED QUASI-ZONAL FLOW ALOFT WILL BE IN PLACE ACROSS THE
REGION TO START SATURDAY AS AN UPPER-LOW TRACKS EASTWARD AWAY
FROM NORTHERN PORTIONS OF NEW ENGLAND. MEANWHILE, A CLOSED LOW
EMBEDDED WITHIN BROADER SCALE TROUGHING WILL PROGRESS
SOUTHEASTWARD OUT OF THE GREAT LAKES TO THE EASTERN SEABOARD
THROUGH SUNDAY NIGHT. AT THE SURFACE, HIGH PRESSURE WILL BUILD
IN TO THE AREA THROUGH SATURDAY AND INTO SUNDAY. MODELS AGREE
THAT AT LEAST MODEST SURFACE PRESSURE FALLS ARE LIKELY WITH THE
APPROACH OF THE CLOSED LOW SUNDAY INTO SUNDAY NIGHT.
IN TERMS OF SENSIBLE WEATHER, SATURDAY AND SUNDAY WILL LIKELY
BE VERY SIMILAR TO ONE ANOTHER, FEATURING PARTLY CLOUDY SKIES
AREAWIDE WITH AFTERNOON HIGHS RANGING FROM THE MID 50S ACROSS
MOST OF EASTERN PA AND NORTHERN NJ TO LOW 60S ACROSS SOUTHERN NJ
AND THE DELMARVA. BOTH NIGHTS WILL BE CHILLY, THOUGH SOME CLOUD
COVER WILL LIKELY HANG ON ACROSS THE AREA MAKING IT SLIGHTLY
WARMER THAN IT OTHERWISE WOULD BE. NEVERTHELESS, TEMPERATURES
WILL FALL INTO THE MID 30S FOR MOST, SLIGHTLY WARMER FOR COASTAL
LOCATIONS, THE URBAN CORRIDOR, AND THE DELMARVA, WITH A FREEZE
POSSIBLE FOR THE HIGHER ELEVATIONS OF THE POCONOS AND INTO FAR
NORTHERN NJ.
GIVEN THE ANTECEDENT HIGH PRESSURE AND PRESENT DRY AIR, WHILE A
SHOWER OR TWO CAN'T BE RULED OUT SUNDAY AFTERNOON INTO SUNDAY
NIGHT, THE CURRENT EXPECTATION IS FOR THE REGION TO REMAIN DRY.
LONG TERM /MONDAY THROUGH THURSDAY/
A SOMEWHAT COMPLEX AND UNCERTAIN UPPER PATTERN IS EXPECTED TO
EVOLVE THROUGH THE FIRST PART OF NEXT WEEK. AS THE UPPER-LOW
TRACKS OFF OF THE EAST COAST, BROAD TROUGHING WILL REMAIN OVER
THE EASTERN TIER OF THE US. AN EMBEDDED IMPULSE IS EXPECTED TO
PASS THROUGH THE AREA MONDAY INTO MONDAY NIGHT. AT THE SURFACE,
AN ASSOCIATED COLD FRONT WILL PASS THROUGH THE REGION.
MODEL SPREAD IS HIGH REGARDING THE EVOLUTION OF UPPER LEVEL AND
SURFACE FEATURES. FOR EXAMPLE, THE GFS DEVELOPS A SURFACE
CYCLONE OFF THE MID ATLANTIC COAST MONDAY WHICH COULD BRING
RAINFALL TO SOUTHERN PARTS OF THE AREA IF IT WERE TO DEVELOP.
THE DETERMINISTIC ECM DID NOT DEVELOP THIS LOW UNTIL ITS MOST
RECENT RUN, AND ENSEMBLE SUPPORT IS LIMITED. SO FOR NOW, IT
LOOKS LIKE THE BEST CHANCE FOR RAINFALL WILL BE WITH THE PASSAGE
OF THE COLD FRONT MONDAY NIGHT, WITH RELATIVELY LIGHT AMOUNTS.
POPS THIS FORECAST CYCLE ARE GENERALLY AROUND 30% NORTH OF I-78
AND 20% SOUTH.
TUESDAY INTO WEDNESDAY WILL FEATURE HEIGHT RISES ALOFT AND
SURFACE HIGH PRESSURE LOOKS TO ONCE AGAIN ESTABLISH ACROSS THE
AREA. PARTLY TO MOSTLY CLEAR SKIES ARE EXPECTED. WEDNESDAY
NIGHT, OUR NEXT STORM SYSTEM MAY BEGIN TO APPROACH THE AREA
BRINGING INCREASING CLOUDS. SOME SHOWER ACTIVITY IS POSSIBLE
WITH THIS SYSTEM ON THURSDAY. THE NBM HAS CHANCE (30% OR
GREATER) POPS FOR THE NORTHERN HALF OR SO OF THE AREA, AND SEE
NO REASON TO STRAY FROM THAT AT THIS POINT IN TIME.
IT CURRENTLY APPEARS THAT TEMPERATURES DURING THE ENTIRE
EXTENDED PERIOD WILL BE SEASONABLE TO SLIGHTLY BELOW NORMAL.
AVIATION /18Z THURSDAY THROUGH TUESDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF TODAY...MVFR AND IFR CIGS/VSBYS IN RA. RA TAPERS OF BY
22Z. CONDS LIFT TO VFR BETWEEN 22Z AND 00Z. SE WINDS 10 TO 20 KT
WITH 20 TO 30 KT GUSTS, DIMINISHING TO LESS THAN 10 KT BY 22Z.
MODERATE CONFIDENCE.
TONIGHT...VFR EARLY, THEN A ROUND OF MVFR CIGS AFTER 06Z. SW
WINDS 5 TO 10 KT, BECOMING W 15 TO 20 KT WITH GUSTS UP TO 25 KT
LATE. MODERATE CONFIDENCE.
FRIDAY...MVFR CIGS EARLY, THEN VFR BY 15Z. W WINDS 20 TO 25 KT
WITH 30 TO 40 KT GUSTS. HIGH CONFIDENCE.
FRIDAY NIGHT...VFR. W TO NW WINDS 15 TO 20 KT WITH GUSTS UP TO
25 KT IN THE EVENING, DIMINISHING TO 5 TO 10 KT. HIGH
CONFIDENCE.
OUTLOOK...
SATURDAY THROUGH SUNDAY NIGHT...VFR. NO SIGNIFICANT WEATHER.
MONDAY THROUGH MONDAY NIGHT...PRIMARILY VFR. BRIEF PERIODS OF
SUB- VFR CONDITIONS ARE POSSIBLE IN RAIN.
TUESDAY...VFR. NO SIGNIFICANT WEATHER.
MARINE
GALES CONTINUE ON OCEAN WATERS NORTH OF LITTLE EGG INLET
THROUGH THIS EVENING. ONCE THAT ENDS, A SMALL CRAFT ADVISORY
WILL BE NEEDED. ON ALL OTHER WATERS, SCA REMAINS IN EFFECT FOR
TONIGHT.
ON FRIDAY, ANOTHER GALE WARNING IS IN EFFECT AS STRONG WEST
WINDS DEVELOP WITH 35 TO 45 KT GUSTS. GALES END FRIDAY NIGHT,
AND A SCA WILL BE NEEDED ONCE THAT GALE WARNING ENDS.
OUTLOOK...
SATURDAY...SCA CONDITIONS COULD LINGER INTO THE DAY ON SATURDAY
WITH WESTERLY WIND 20-25 KT AND SEAS 5-7 FEET. CONDITIONS
SHOULD IMPROVE THROUGHOUT THE DAY.
SATURDAY NIGHT THROUGH MONDAY NIGHT...NO MARINE HEADLINES ARE
CURRENTLY ANTICIPATED WITH WINDS GENERALLY LESS THAN 25 KT AND
SEAS LESS THAN 5 FEET.
TUESDAY...SCA CONDITIONS ARE POSSIBLE BEHIND A COLD FRONT WITH
ENHANCED WESTERLY WINDS AND ELEVATED SEAS.
TIDES/COASTAL FLOODING
A PROLONGED PERIOD OF COASTAL FLOOD IMPACTS WITH POTENTIAL FOR
BEACH EROSION IS ANTICIPATED TO IMPACT THE ATLANTIC COASTS OF
NEW JERSEY, DELAWARE, THE DELAWARE BAY, THE EASTERN SHORE OF THE
CHESAPEAKE BAY, AND THE TIDAL DELAWARE RIVER THROUGH FRIDAY
MORNING. THIS IS DUE TO A STRENGTHENING STORM SYSTEM ACROSS THE
MID-ATLANTIC TODAY WHICH WILL STRENGTHEN ONSHORE WINDS. SURGE
AND TIDE LEVELS WILL CONTINUE TO INCREASE THROUGH TODAY AS A
RESULT. WINDS WILL THEN SHIFT OFFSHORE FROM THE WEST TONIGHT
INTO EARLY FRIDAY, PUTTING AN END TO THE COASTAL FLOOD THREAT.
IN TERMS OF HAZARDS, THE COASTAL FLOOD ADVISORIES FOR ATLANTIC
AND CAPE MAY COUNTIES IN NEW JERSEY, AND SUSSEX AND KENT
COUNTIES IN DELAWARE REMAIN UNCHANGED. OCEAN COUNTY HAS BEEN
UPGRADED TO A COASTAL FLOOD WARNING.
A COASTAL FLOOD ADVISORY HAS ALSO BEEN ISSUED FOR THE SOUTH
SHORE OF THE RARITAN BAY, NORTHERN NEW JERSEY COAST, THE
REMAINDER OF THE DELAWARE BAY AND THE EASTERN SHORE OF THE
CHESAPEAKE BAY FOR TODAY AND TONIGHT'S HIGH TIDE CYCLES. KENT
COUNTY MARYLAND WAS ALSO UPGRADED TO A COASTAL FLOOD WARNING.
FOR THE TIDAL DELAWARE RIVER, CONFIDENCE HAS INCREASED THAT
BETWEEN WINDS CONTINUING TO PUSH WATER UPSTREAM INTO THE RIVER
AS WELL AS FRESHWATER RUNOFF FROM RAINFALL INCREASING WATER
LEVELS, THAT WE WILL SEE WIDESPREAD MINOR TIDAL FLOODING AT HIGH
TIDE LATER THIS EVENING. AS A RESULT, THE COASTAL FLOOD
ADVISORY HAS BEEN EXPANDED TO INCLUDE THE TIDAL DELAWARE RIVER
FOR THIS EVENING'S HIGH TIDE.
REMAIN ALERT FOR ADDITIONAL FORECAST UPDATES AND INFORMATION
REGARDING THIS LONG DURATION COASTAL FLOOD EVENT.
CLIMATE
WIDESPREAD MODERATE TO HEAVY RAINFALL HAS OCCURRED ACROSS THE
AREA TODAY, THURSDAY, OCTOBER 30TH. BELOW IS A LIST OF THE DAILY
PRECIPITATION RECORDS FOR THE DATE:
OCTOBER 30TH DAILY PRECIPITATION RECORDS
ALLENTOWN (ABE) 1.50" IN 1917 & 1935
AC AIRPORT (ACY) 1.28" IN 2021
AC MARINA (55N) 6.02" IN 1886
GEORGETOWN (GED) 0.97" IN 1955
MOUNT POCONO (MPO) 4.00" IN 1935
PHILADELPHIA (PHL) 1.77" IN 1935
READING (RDG) 1.22" IN 1973
TRENTON (TTN) 2.90" IN 1866
WILMINGTON (ILG) 1.24" IN 1935
PHI WATCHES/WARNINGS/ADVISORIES
PA...WIND ADVISORY FROM 10 AM TO 8 PM EDT FRIDAY FOR PAZ054-055-
060>062-070-071-101>106.
COASTAL FLOOD ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR PAZ070-071-106.
NJ...COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ016.
WIND ADVISORY FROM 10 AM TO 8 PM EDT FRIDAY FOR NJZ001-007>010-
012-013-015>023-027.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
NJZ012>014-021>025-027.
WIND ADVISORY FROM 10 AM TO 11 PM EDT FRIDAY FOR NJZ014-
024>026.
COASTAL FLOOD ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR NJZ017>019.
COASTAL FLOOD WARNING UNTIL 10 PM EDT THIS EVENING FOR NJZ020-
026.
DE...COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DEZ001.
WIND ADVISORY FROM 10 AM TO 8 PM EDT FRIDAY FOR DEZ001>004.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
DEZ002>004.
MD...COASTAL FLOOD WARNING UNTIL 6 PM EDT THIS EVENING FOR MDZ012.
COASTAL FLOOD ADVISORY UNTIL 3 AM EDT FRIDAY FOR MDZ015-019-
020.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR ANZ430-431-
452>455.
GALE WARNING FROM 6 AM FRIDAY TO MIDNIGHT EDT FRIDAY NIGHT FOR
ANZ430-431.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR ANZ450-451.
GALE WARNING FROM 6 AM FRIDAY TO 2 AM EDT SATURDAY FOR
ANZ450>455.
SYNOPSIS...COOPER
NEAR TERM...MPS
SHORT TERM...COOPER
LONG TERM...COOPER
AVIATION...COOPER/MPS
MARINE...COOPER/MPS
TIDES/COASTAL FLOODING...
CLIMATE...
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page