819
FXUS61 KPHI 261857
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
257 PM EDT WED AUG 26 2026
WHAT HAS CHANGED
SEVERE AND FLASH FLOOD POTENTIAL HAS INCREASED FOR THURSDAY.
KEY MESSAGES
1. A WARM FRONT ON THURSDAY WILL BRING THE NEXT CHANCE FOR
WIDESPREAD RAIN.
2. A COLD FRONT IS EXPECTED TO FOLLOW CLOSE BEHIND ON FRIDAY.
DISCUSSION
KEY MESSAGE 1...A WARM FRONT TOMORROW WILL BRING THE NEXT
CHANCE FOR WIDESPREAD RAIN.
HIGH PRESSURE MOVES OFFSHORE WITH SOUTHERLY RETURN FLOW BEHIND
A WARM FRONT WILL BRING DEW POINTS INTO THE LOW 70S. SHOWERS AND THUNDERSTORMS
WILL START MOVING INTO WESTERN AREAS BEFORE DAYBREAK AND CONTINUE
THROUGH THE DAY. CAMS PRODUCING SOME ORGANIZATION TO CONVECTIVE
ACTIVITY LARGELY FOCUSED ON THE I-95 URBAN CORRIDOR.
AS FOR THE HAZARDS, THERE IS A SLIGHT (2 OUT OF 4) RISK FOR
EXCESSIVE RAINFALL. PRECIPITABLE WATER VALUES INCREASE TO
PERHAPS AS HIGH AS 150% OF NORMAL FOR THIS TIME OF YEAR.
THE HIRES GUIDANCE SUGGESTS THAT HEAVIEST PRECIPITATION WILL BE
GENERALLY ALONG THE I-95 CORRIDOR AND POINTS NORTHWEST.
GENERALLY AROUND 1-2 INCHES OF RAIN WITH OCALIZED QPF VALUES IN
EXCESS OF 3 INCHES. WIDESPREAD FLASH FLOODING STILL SEEMS
UNLIKELY, BUT THE LOCALIZED THREAT HAS INCREASED AND HAVE ISSUED
A FLOOD WATCH FOR THE URBAN CORRIDOR FROM ILG-NORTHERN NJ
FOR SEVERE HAZARDS, LATEST CAMS AND HREF GUIDANCE HAS COME COME
INTO LINE WITH MORE INSTABILITY AVAILABLE FOR STORMS TO WORK
WITH TOMORROW. HREF MEAN SBCAPE VALUES ARE AROUND 1500-2500
J/KG WITH ENSEMBLE MAXIMUMS IN EXCESS 3000 J/KG. DEEP LAYER
SHEAR FORECASTS HAVE NOW INCREASED TO AROUND 30KT. BOUNDARY
LAYER FLOW IS NOT PARTICULARLY STRONG BUT SURFACE WINDS ARE MORE
BACKED THAN PREVIOUS FORECASTS SO AN ISOLATED TORNADO IS
POSSIBLE PRIMARILY ALONG AND WEST OF I-95. DOMINANT MODE SHOULD
BE MULTICELL CONVECTION BUT A SUPERCELL CAN'T BE RULED OUT
ESPECIALLY WHERE CLOUD BEARING SHEAR IS MAXIMIZED. SPC HAS
EXPANDED THE AREA OF A SLIGHT RISK (2 OUT OF 4) TO NOW INCLUDE
MUCH OF THE AREA.
KEY MESSAGE 2...A COLD FRONT WILL CROSS THE AREA FRIDAY.
THE TIMING OF THIS COLD FRONT WILL BE CRITICAL IN THE RISK FOR
THUNDERSTORM HAZARDS. THERE ARE DIFFERENCES BETWEEN MODELS IN
BOTH THE TIMING, AND IF THIS WILL BE A SINGLE COLD FRONT, OR AN
INITIAL COLD FRONT WITH A REINFORCING SHOT OF COLD AIR ADVECTION
COMING IN BEHIND IT. SATURDAY AND SUNDAY APPEAR TO BE DRY ACROSS
MOST OF THE AREA WITH THE EXCEPTION OF SOUTHERN AREAS SATURDAY
WHERE LOW PROBABILITIES OF SHOWERS AND STORMS WILL EXIST.
AVIATION /18Z WEDNESDAY THROUGH MONDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT (THROUGH 12Z)...VFR. WINDS LIGHT AND VARIABLE.
THURSDAY...PREDOMINANTLY VFR. LIGHT SOUTH WINDS IN THE MORNING
BECOME MORE OUT OF THE SOUTH SOUTHWEST AT AROUND 10 KNOTS DURING
THE AFTERNOON. SHOWERS AND THUNDERSTORMS ARE POSSIBLE FROM MID
DAY ON, BUT DETAILS ON TIMING ARE TOO UNCERTAIN TO INCLUDE
CATEGORICAL GROUPS. HAVE VCTS AND PROB30S.
OUTLOOK...
FRIDAY...PERIODS OF MVFR OR LOWER ARE POSSIBLE IN SHOWERS AND
STORMS.
SATURDAY THROUGH MONDAY...PREVAILING VFR CONDITIONS.
MARINE
NO MARINE HAZARDS EXPECTED. LIGHT WINDS AND NO RESTRICTIONS TO
VISIBILITY EXPECTED WEDNESDAY.
OUTLOOK...
THURSDAY AND FRIDAY...GUSTS NEAR 20 KT ARE POSSIBLE,
PARTICULARLY ON THURSDAY WITH SOUTHERLY WINDS BEHIND A WARM
FRONT.
SATURDAY AND SUNDAY...NO MARINE HAZARDS EXPECTED.
RIP CURRENTS...
ON WEDNESDAY, WINDS WILL SHIFT SOUTHERLY AND INCREASE TO NEAR
10 TO 15 MPH IN THE AFTERNOON. A MEDIUM PERIOD SWELL WILL
PERSIST WITH BREAKING WAVES AROUND 2 FEET DURING MUCH OF THE
DAYTIME. AS A RESULT, THERE IS A LOW RISK FOR THE DEVELOPMENT OF
DANGEROUS AND LIFE THREATENING RIP CURRENTS AT THE JERSEY SHORE
AND AT DELAWARE BEACHES.
FOR THURSDAY, WINDS REMAIN SOUTHERLY AT 10 TO 15 MPH WITH GUSTS
TO 20 MPH. AN EAST-SOUTHEASTERLY SWELL REMAINS WITH A PERIOD OF
8-9 SECONDS WITH BREAKING WAVES AROUND 2-3 FEET. AS A RESULT,
THERE IS A MODERATE RISK FOR THE DEVELOPMENT OF DANGEROUS AND
LIFE THREATENING RIP CURRENTS AT THE JERSEY SHORE AND A LOW RISK
AT DELAWARE BEACHES.
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI
PHI WATCHES/WARNINGS/ADVISORIES
PA...FLOOD WATCH FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY
NIGHT FOR PAZ070-071-101>106.
NJ...FLOOD WATCH FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY
NIGHT FOR NJZ001-008>010-012-013-015-017>019.
DE...FLOOD WATCH FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY
NIGHT FOR DEZ001.
MD...NONE.
MARINE...NONE.
DISCUSSION...WFO PHI
AVIATION...WFO PHI
MARINE...WFO PHI
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