548
FXUS61 KPHI 141859
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
259 PM EDT WED OCT 14 2026
WHAT HAS CHANGED
SMALL CRAFT ADVISORIES HAVE BEEN ISSUED FOR THE ATLANTIC COASTAL
WATERS FROM CAPE MAY TO FENWICK ISLAND FOR EARLY THURSDAY
MORNING.
GALE WATCH ISSUED FOR ALL ATLANTIC WATERS AND DELAWARE BAY FOR
FRIDAY NIGHT THROUGH SATURDAY.
THE WIND FORECAST FOR FRIDAY INTO FRIDAY NIGHT HAS LESSENED
SOME.
KEY MESSAGES
1. A COLD FRONT WILL SINK SOUTH THROUGH THE REGION THIS EVENING
YIELDING COOLER WEATHER FOR THURSDAY.
2. A STRONG COLD FRONT PASSAGE FRIDAY EVENING WILL BRING WINDY
CONDITIONS, SHOWERS AND POTENTIAL FOR SOME THUNDERSTORMS, AND
COLDER TEMPERATURES INTO THE WEEKEND.
3. WIDESPREAD FROST AND FREEZE CONDITIONS ARE INCREASINGLY
LIKELY SATURDAY NIGHT.
DISCUSSION
KEY MESSAGE 1...A COLD FRONT WILL SINK SOUTH THROUGH THE REGION
THIS EVENING YIELDING COOLER WEATHER FOR THURSDAY.
LOW PRESSURE TRACKING ACROSS NORTHERN NEW ENGLAND WILL MOVE
INTO NOVA SCOTIA TONIGHT. ASSOCIATED WITH THIS LOW IS A FRONTAL
BOUNDARY THAT EXTENDS SOUTHWEST INTO THE OHIO VALLEY. THIS FRONT
WILL CONTINUE TO SLIDE SOUTH ACROSS THE REGION THIS AFTERNOON
AND INTO THIS EVENING. AFTER A ROUND OF SHOWERS AND SOME RUMBLES
OF THUNDER EARLIER TODAY, TEMPERATURES HAVE BEEN KNOCKED DOWN
INTO THE 70S FOR MANY AREAS. SOME RECOVERY IS POSSIBLE FOR THE
REST OF THE AFTERNOON WITH HIGHS STILL FORECAST TO TOP OUT IN
THE LOW 80S FOR THESE AREAS. ELSEWHERE, TEMPERATURES HAVE
REMAINED WELL INTO MID TO UPPER 80S UNDER MOSTLY SUNNY SKIES.
SOME SHOWERS REMAIN POSSIBLE IN SOUTHERN AREAS THROUGH THE EARLY
EVENING HOURS BEFORE DIMINISHING.
AFTER THE FRONT PASSES BY THIS EVENING, COOLER AIR WILL BRIEFLY
RETURN OVERNIGHT TONIGHT INTO THURSDAY. WITH SKIES CLEARING
ACROSS NORTHERN AREAS OVERNIGHT, LOWS IN THE 50S ARE EXPECTED
FOR MOST AREAS, WITH 40S IN THE HIGHER ELEVATIONS. FOR SOUTHERN
AREAS, MORE IN THE WAY OF CLOUD COVER IS EXPECTED TO PERSIST,
WHICH WILL KEEP OVERNIGHT LOWS MOSTLY IN THE 60S. FOR THURSDAY,
MUCH OF THE DAY IS EXPECTED TO BE DRY WITH A MIX OF SUN AND
CLOUDS. HOWEVER, THE FRONT WILL BEGIN TO SLOWLY WORK ITS WAY
BACK NORTH LATE IN THE DAY, SO CANNOT RULE OUT A FEW SHOWERS
ACROSS THE DELMARVA AS A RESULT. HIGHS WILL BE GENERALLY UNIFORM
IN THE LOW TO MID 60S WITH ONSHORE FLOW.
KEY MESSAGE 2...A STRONG COLD FRONT PASSAGE FRIDAY EVENING WILL
BRING WINDY CONDITIONS, SHOWERS AND POTENTIAL FOR SOME
THUNDERSTORMS, AND COLDER TEMPERATURES INTO THE WEEKEND.
A SHARP UPPER-LEVEL TROUGH IS FORECAST TO ARRIVE ACROSS THE
EAST COAST ON FRIDAY, THEN GRADUALLY LIFT OUT OVER THE WEEKEND.
THIS WILL DRIVE RAPIDLY STRENGTHENING SURFACE LOW PRESSURE JUST
NORTH OF OUR AREA FRIDAY, WITH AN ASSOCIATED STRONG COLD FRONT
SWEEPING THROUGH. A CONSENSUS OF GUIDANCE HAS SLOWED THE PASSAGE
OF THE FRONT LATER IN THE DAY, MOST LIKELY DURING THE EVENING
HOURS (4-8 PM), LIKELY MOVING FROM OUR WESTERN MOST ZONES AND
OFFSHORE WITHIN ABOUT 3 HOURS OR SO.
A WARM AND INCREASINGLY MOIST AIRMASS AHEAD OF THIS SYSTEM WILL
PROVIDE MODEST INSTABILITY AND DECENT BOUNDARY LAYER MIXING AS
THE STRONG COLD FRONT APPROACHES ON FRIDAY. LARGE SCALE FORCING
FOR ASCENT WILL INCREASE WITH THE ARRIVAL OF THE ROBUST UPPER-
LEVEL TROUGH AND COLD FRONT. IT APPEARS THERE WILL BE A ROUND OF
SHOWERS AND A FEW THUNDERSTORMS OVERNIGHT THURSDAY NIGHT INTO
EARLY FRIDAY MORNING ASSOCIATED WITH THE WARM ADVECTION SURGE
ALOFT. THERE SHOULD THEN BE A BREAK IN CONVECTION BY MIDDAY
PRIOR TO THE COLD FRONT'S ARRIVAL LATE IN THE DAY AND INTO THE
EVENING. A LINE OR BROKEN LINE OF SHOWERS AND STORMS SHOULD
DEVELOP ALONG OR JUST AHEAD OF THE FRONT. CANNOT RULE OUT SOME
SEVERE THUNDERSTORM POTENTIAL, ESPECIALLY IF ANY MORE ROBUST
CONVECTION CAN MATERIALIZE ALONG THE COLD FRONT.
WHILE IT WILL BE MOSTLY CLOUDY, STRONG WARM ADVECTION WILL
BOOST TEMPERATURES UP WELL INTO THE 70S AND LOW 80S AHEAD OF THE
FRONT. AS SURFACE PRESSURE FALLS RAPIDLY AMID A STRENGTHENING
SOUTHWESTERLY GRADIENT, BREEZY CONDITIONS WILL LIKELY DEVELOP
OUTSIDE OF ANY SHOWERS AND STORMS WITH GUSTS OF 20-30 MPH
POSSIBLE.
DURING AND AFTER COLD FRONTAL PASSAGE, STRONG COLD AIR
ADVECTION WILL OCCUR AS THE SHARP TROUGH ALOFT SWEEPS THROUGH.
HOWEVER, THE TIMING OF THIS NOW LOOKS TO TRAIL BEHIND THE FRONT
UNTIL SOMETIME AFTER MIDNIGHT. THIS WILL SUPPORT EFFICIENT
MIXING OF WINDS ALOFT DOWN TOWARD THE SURFACE IN THE FORM OF
FREQUENT WIND GUSTS AS TEMPERATURES PLUMMET INTO THE 50S THEN
40S OVERNIGHT. BOUNDARY LAYER WINDS COULD BE AS HIGH AS 40-50
MPH FOR A FEW HOURS IN THE WAKE OF THE FRONT, WHICH COULD
WARRANT A WIND ADVISORY. HOWEVER, THE THREAT OF WINDS OF THIS
MAGNITUDE HAVE LESSENED SOME GIVEN THE LATER TIMING OF THE
SYSTEM. THE TIMING OF THE PEAK WINDS NOW APPEARS TO BE FOCUSED
DURING THE OVERNIGHT HOURS AND INTO SATURDAY MORNING, WITH GUSTS
OF 30-40 MPH LIKELY.
THE COLDEST AIRMASS SO FAR THIS SEASON WILL SETTLE INTO THE
AREA SATURDAY INTO SATURDAY NIGHT. HIGH TEMPERATURES SATURDAY
ARE ONLY IN THE LOW TO MID 50S IN MOST AREAS (40S NORTH OF
I-78). BREEZY CONDITIONS WILL CONTINUE, WITH NORTHWEST WINDS
GUSTING 30-40 MPH POSSIBLE IN THE MORNING BEFORE GRADUALLY
DIMINISHING LATER IN THE DAY.
KEY MESSAGE 3...WIDESPREAD FROST AND FREEZE CONDITIONS ARE
INCREASINGLY LIKELY SATURDAY NIGHT.
AS STRONG SURFACE HIGH PRESSURE SETTLES NEARLY OVERHEAD INTO
SATURDAY NIGHT, TEMPERATURES WILL COOL SIGNIFICANTLY WITH
RADIATIONAL COOLING. THIS SHOULD RESULT IN WIDESPREAD LOW
TEMPERATURES IN THE 30S SATURDAY NIGHT INTO SUNDAY MORNING, AND
POTENTIALLY INTO THE UPPER 20S NORTH OF I-78. THIS WILL
INTRODUCE OUR FIRST WIDESPREAD FROST AND FREEZE POTENTIAL OF THE
SEASON. A FREEZE APPEARS UNLIKELY SOUTH OF I-78, BUT THE USUAL
COLD SPOTS (INCLUDING THE PINE BARRENS) COULD DROP TO NEAR THE
FREEZING MARK. ASIDE FROM THE FREEZE POTENTIAL, AREAS OF FROST
ARE ANTICIPATED, ESPECIALLY ACROSS MUCH OF OUR NJ, PA, AND
NORTHERN DE AREAS. DELMARVA COULD ALSO GET IN ON THE FROST
THREAT.
THE AIRMASS WILL START TO MODIFY SUNDAY AND INTO EARLY NEXT
WEEK. HIGHS SUNDAY SHOULD REBOUND INTO THE MID 50S TO NEAR 60
DEGREES IN MOST AREAS WITH WINDS 5-10 MPH MAKING FOR A MUCH MORE
PLEASANT DAY COMPARED TO SATURDAY. THERE COULD BE SOME FROST
POTENTIAL SUNDAY NIGHT, BUT LOWS ARE LIKELY TO REBOUND INTO THE
UPPER 30S TO LOW 40S IN MOST AREAS. TEMPERATURES WILL THEN
REBOUND TO NEAR NORMAL VALUES, WITH HIGHS WELL INTO THE 60S
EARLY NEXT WEEK AND DRY WEATHER EXPECTED.
AVIATION /18Z WEDNESDAY THROUGH MONDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF TODAY...VFR. SHOWERS POSSIBLE FOR THE NEXT FEW HOURS,
DIMINISHING AFTER 21Z FROM NORTH TO SOUTH. WEST WINDS GENERALLY
AROUND 10 KT, GUSTING UP TO 15-18 KT DURING THE AFTERNOON.
MODERATE-HIGH CONFIDENCE OVERALL.
TONIGHT...VFR. A SLIGHT CHANCE OF SHOWERS AT MIV AND ACY IN THE
EARLY EVENING, WANING AFTER MIDNIGHT. NORTHWEST WINDS AROUND
5-10 KT WILL SETTLE OUT OF THE NORTH-NORTHEAST OVERNIGHT. HIGH
CONFIDENCE.
THURSDAY...VFR. MOSTLY CLEAR SKIES FOR MUCH OF THE DAY, WITH
INCREASING CLOUDS LATE. NORTHEAST WINDS AROUND 5-10 KT IN THE
MORNING, SETTLE OUT OF THE EAST-SOUTHEAST IN THE AFTERNOON. HIGH
CONFIDENCE.
OUTLOOK...
THURSDAY NIGHT AND FRIDAY...PERIODS OF RESTRICTIONS PROBABLE
DURING THIS PERIOD IN SHOWERS AND LOW CEILINGS. POTENTIAL FOR
THUNDERSTORMS AS WELL. SOUTHWEST WINDS FRIDAY SHIFTING NORTHWEST
FRIDAY EVENING WITH GUSTS UP TO 40 KTS POSSIBLE.
SATURDAY THROUGH MONDAY...VFR. NORTHWEST WINDS GUSTING UP TO 30
KTS ON SATURDAY.
MARINE
SMALL CRAFT ADVISORIES HAVE BEEN ISSUED FOR THE ATLANTIC
COASTAL WATERS FROM CAPE MAY TO FENWICK ISLAND BEGINNING AT 5 AM
THURSDAY.
WEST-SOUTHWEST WINDS AROUND 10-15 KT THIS AFTERNOON WILL BECOME
NORTHWEST THIS EVENING. AFTER MIDNIGHT, A SURGE IN NORTH-
NORTHEAST WINDS IS EXPECTED AROUND 15-20 KT WITH GUSTS UP TO 25
KT POSSIBLE, MAINLY ACROSS SOUTHERN WATERS THROUGH THURSDAY
MORNING. NORTHEAST WINDS WILL THEN DIMINISH TO AROUND 10-20 KT
FOR THE REST OF THURSDAY. SEAS OF 3-4 FEET.
ASIDE FOR A SLIGHT CHANCE OF SHOWERS THIS EVENING, FAIR WEATHER
IS EXPECTED OUTSIDE OF SCA AREAS.
OUTLOOK...
FRIDAY AND SATURDAY...SMALL CRAFT ADVISORY CONDITIONS
DEVELOPING DURING THE DAYTIME FRIDAY, THEN GALE FORCE WINDS
POSSIBLE FRIDAY NIGHT INTO SATURDAY AS A STRONG COLD FRONT
PUSHES OFFSHORE FRIDAY EVENING. SEAS BUILDING OVER 5 FEET. HEAVY
SHOWERS AND A FEW THUNDERSTORMS WILL ACCOMPANY THE FRONT AS IT
PUSHES OFFSHORE FRIDAY NIGHT, ALONG WITH LOCALLY STRONGER WINDS
AND HIGHER SEAS. A GALE WATCH WAS ISSUED FOR ALL ATLANTIC
WATERS AND DELAWARE BAY FOR FRIDAY NIGHT THROUGH SATURDAY.
SATURDAY NIGHT THROUGH MONDAY...LINGERING SCA CONDITIONS EARLY
SATURDAY NIGHT. OTHERWISE, NO MARINE HAZARDS ARE ANTICIPATED.
CLIMATE
NEAR RECORD BREAKING HIGH TEMPERATURES ARE FORECAST FOR TODAY.
RECORDS FOR OUR CLIMATE STATIONS ARE LISTED BELOW:
RECORD HIGH TEMPERATURES
OCTOBER 14
SITE RECORD/YEAR
ALLENTOWN (ABE) 86/1975
AC AIRPORT (ACY) 83/1990
AC MARINA (55N) 84/1975 & 1990
GEORGETOWN (GED) 87/1954
MOUNT POCONO (MPO) 79/1995
PHILADELPHIA (PHL) 88/1975
READING (RDG) 82/1920
TRENTON (TTN) 86/1975
WILMINGTON (ILG) 87/1975
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR
ANZ430-431-450>455-480>483-485.
SMALL CRAFT ADVISORY FROM 5 AM TO 11 AM EDT THURSDAY FOR
ANZ454-455.
DISCUSSION...DESILVA/MJL/STAARMANN
AVIATION...DESILVA/STAARMANN
MARINE...DESILVA/STAARMANN
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