801
FXUS61 KPHI 150549
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
149 AM EDT MON JUN 15 2026
WHAT HAS CHANGED
SEVERE THUNDERSTORM WATCH AND THE COASTAL FLOOD ADVISORY HAVE
BEEN ALLOWED TO EXPIRE. UPDATED THESE KEY MESSAGES AND ALSO
UPDATED AVIATION SECTION FOR 06Z TAFS.
KEY MESSAGES
1. THE SEVERE WEATHER THREAT HAS ENDED BUT THERE ARE STILL
LINGERING SHOWERS. SHOWERS SHOULD BE LARGELY OUT OF THE AREA BY
3 AM HOWEVER THERE MAY CONTINUE TO BE SOME LINGERING AREAS OF
FLOODING THROUGH THE OVERNIGHT AS WATER LEVELS ON CREEKS AND
STREAMS NEAR THE I-95 CORRIDOR ARE ELEVATED.
2. THE COASTAL FLOOD ADVISORY HAS BEEN ALLOWED TO EXPIRE HOWEVER
ANOTHER ROUND OF MINOR COASTAL FLOODING WILL BE POSSIBLE WITH
THE MONDAY EVENING HIGH TIDE CYCLE.
3. SOME SEVERE THUNDERSTORMS POSSIBLE THURSDAY AFTERNOON AND EVENING.
DISCUSSION
KEY MESSAGE 1..THE SEVERE WEATHER THREAT HAS ENDED BUT THERE
ARE STILL LINGERING SHOWERS. SHOWERS SHOULD BE LARGELY OUT OF
THE AREA BY 3 AM HOWEVER THERE MAY CONTINUE TO BE SOME LINGERING
AREAS OF FLOODING THROUGH THE OVERNIGHT AS WATER LEVELS ON
CREEKS AND STREAMS NEAR THE I-95 CORRIDOR ARE ELEVATED.
AS OF 1 AM, THE COLD FRONT IS MOVING THROUGH OUR EASTERN PA
ZONES. THE FRONT WILL CONTINUE MOVING EASTWARD AND WILL CLEAR
THE COAST BY AROUND 5 AM. AS THIS OCCURS LINGERING SHOWERS WILL
EXIT THE REGION. HOWEVER WATER LEVELS ON CREEKS AND STREAMS NEAR
THE I-95 CORRIDOR ARE ELEVATED SO LOCALIZED FLOODING WILL
REMAIN A CONCERN THROUGH MOST OF THE NIGHT. NO ADDITIONAL SEVERE
WEATHER IS EXPECTED THOUGH.
KEY MESSAGE 2...THE COASTAL FLOOD ADVISORY HAS BEEN ALLOWED TO EXPIRE HOWEVER
ANOTHER ROUND OF MINOR COASTAL FLOODING WILL BE POSSIBLE WITH
THE MONDAY EVENING HIGH TIDE CYCLE.
A NEW MOON IS OCCURRING THIS WEEKEND AND RESULTING IN HIGHER
THAN NORMAL ASTRONOMICAL TIDES. THE TIDAL FLOODING THREAT WITH
THIS PAST EVENING'S HIGH TIDE CYCLE HAS COME TO AN END BUT AT
LEAST ONE MORE ROUND OF SOME MINOR COASTAL FLOODING APPEARS
LIKELY WITH THE MONDAY EVENING HIGH TIDE CYCLE FOR THE ATLANTIC
COAST AND DELAWARE BAY.
TIDAL FLOODING IS NOT CURRENTLY EXPECTED ALONG THE EASTERN
SHORE OF CHESAPEAKE BAY.
KEY MESSAGE 3...SOME SEVERE THUNDERSTORMS POSSIBLE THURSDAY AFTERNOON
AND EVENING.
AN UPPER-LEVEL TROUGH CENTERED OVER SOUTH-CENTRAL CANADA IS FORECAST
TO STRENGTHEN EASTWARD AND ALSO SOUTHWARD ACROSS THE GREAT LAKES TO
END THE WEEK. A STRONG SHORTWAVE ROUNDING THE BASE OF THIS TROUGH
MAY RESULT IN A PORTION OF IT TAKING ON A NEGATIVE TILT ACROSS THE
EASTERN GREAT LAKES AND TOWARD NEW ENGLAND LATE WEDNESDAY AND THURSDAY.
THIS FEATURE IS A BIT STRONGER IN THE ECMWF SOLUTION, WHILE THE
GFS ENSEMBLES ARE MOSTLY A LITTLE WEAKER. A DEEPENING SURFACE LOW
WILL ACCOMPANY IT AND TRACK ACROSS THE EASTERN GREAT LAKES AND INTO
ADJACENT CANADA DURING THURSDAY. A STRONG COLD FRONT WILL THEN ARRIVE
INTO OUR AREA THURSDAY AFTERNOON OR THURSDAY EVENING.
AS THE SYNOPTIC PATTERN EVOLVES, THE FLOW WILL INCREASE OUT OF THE
SOUTH AND SOUTHWEST. THIS WILL ADVECT DEEPER MOISTURE NORTHWARD, AND
IN TANDEM WITH STRENGTHENING WARM AIR ADVECTION WILL LEAD TO
INCREASED INSTABILITY DURING THE DAY THURSDAY. IN ADDITION, A STRONG
MID TO UPPER LEVEL JET IS FORECAST TO EXTEND EASTWARD FROM THE
EASTERN GREAT LAKES. WHILE THE CORE OF THE 500 MB JET (80-100 KNOTS)
IS FORECAST TO REMAIN MAINLY NORTHWEST OF OUR AREA, 40-70 KNOTS OF
FLOW AT 500 MB IS STILL FORECAST ACROSS OUR AREA THURSDAY AFTERNOON
INTO THE EVENING. THIS INCREASED FLOW WILL RESULT IN GREATER SHEAR
MAGNITUDES. WHILE THERE REMAINS SOME TIMING DIFFERENCES AMONG THE
GUIDANCE REGARDING THE MAIN FEATURES, THE CONSENSUS IS THAT ENOUGH
INSTABILITY SHOULD OVERLAP WITH THE STRONGER SHEAR ALONG WITH
INCOMING STRONGER FORCING. AS A RESULT, THERE CONTINUES TO BE SOME
SEVERE THUNDERSTORM POTENTIAL THURSDAY AFTERNOON AND EVENING. AS OF
NOW, LOCALLY DAMAGING WINDS ARE THE PRIMARY THREAT ESPECIALLY IF
CONVECTION DEVELOPS INTO A SQUALL LINE. HOWEVER IF SHEAR AND
INSTABILITY ENDS UP BEING EVEN GREATER, THAN ALL SEVERE THUNDERSTORM
HAZARDS MAY COME INTO PLAY ESPECIALLY IF THE MODE IS DISCRETE FOR A
TIME. THE DETAILS REMAIN MUCH LESS CERTAIN AT THIS TIME RANGE GIVEN
THE TYPICAL UNCERTAINTY WITH INSTABILITY AND THE THERMODYNAMIC
PROFILES. THE FORECAST SYNOPTIC SETUP HOWEVER WITH A DEEPENING
SURFACE LOW TRACKING TO OUR NORTHWEST WITH STRONG FLOW WITHIN A
WARMER AND MORE MOIST ENVIRONMENT SUGGESTS SOME RISK FOR SEVERE
THUNDERSTORMS. IN ADDITION, THE MAIN TROUGH MAY END UP ARRIVING ON
FRIDAY WITH SOME ADDITIONAL CHANCES FOR SHOWERS AND SOME
THUNDERSTORMS.
THE I-95 CORRIDOR AND THE COASTAL PLAIN (AWAY FROM THE IMMEDIATE
COAST) LOOKS TO BE THE HOTTEST DURING THURSDAY AHEAD OF THE
CONVECTION, WITH THE HEAT INDICES POTENTIALLY GETTING VERY CLOSE TO
100 DEGREES.
AVIATION /06Z MONDAY THROUGH FRIDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF OVERNIGHT...LINGERING MVFR CONDITIONS WILL IMPROVE TO
VFR BETWEEN 6 AND 9Z AS A COLD FRONT SWEEPS THROUGH THE AREA. AS
THIS OCCURS WSW WINDS WILL SHIFT TO NW AROUND 10 KNOTS. HIGH
CONFIDENCE.
MONDAY...VFR WITH A FEW/SCATTERED CLOUDS IN THE
AFTERNOON. NORTHWEST WINDS AROUND 10-15 KT, OCCASIONALLY GUSTING
UP TO 20 KT. HIGH CONFIDENCE.
OUTLOOK...
MONDAY NIGHT...VFR. NORTHWEST WINDS QUICKLY DIMINISH AND BECOMING
LIGHT AND VARIABLE.
TUESDAY...MAINLY VFR.
WEDNESDAY...SOME SUB-VFR CONDITIONS WITH A FEW SHOWERS OR A
THUNDERSTORM POSSIBLE.
THURSDAY...A PERIOD OF SUB-VFR CONDITIONS PROBABLE IN THE AFTERNOON
AND EVENING AS SHOWERS AND SOME THUNDERSTORMS INCREASE.
FRIDAY...SOME SHOWERS AND THUNDERSTORMS MAY LINGER WITH AREAS OF SUB-
VFR CONDITIONS POSSIBLE AT TIMES.
MARINE
THE SMALL CRAFT ADVISORY FOR PORTION OF OUR ATLANTIC COASTAL
WATERS AND THE DELAWARE BAY HAS BEEN EXTENDED UNTIL 3 AM.
WINDS WILL DIMINISH OVERNIGHT AS WINDS TURN NORTHWESTERLY
BEHIND A COLD FRONT. NORTHWEST WINDS WILL GENERALLY REMAIN
AROUND 15-20 KT THROUGH MONDAY MORNING, HOWEVER A FEW ROGUE
GUSTS UP TO 22-23 KT ARE POSSIBLE BEFORE FURTHER DIMINISHING
THROUGHOUT THE DAY. SEAS GENERALLY AROUND 2-4 FEET, LOCALLY 5
FEET TONIGHT, AND AROUND 2-3 FEET ON MONDAY.
SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH TONIGHT, WHICH MAY
CAUSE LOCALIZED HIGHER WINDS/SEAS. SOME MARINE FOG POSSIBLE TONIGHT
AS WELL. ON MONDAY, FAIR WEATHER EXPECTED.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...THE CONDITIONS ARE ANTICIPATED TO
BE BELOW SMALL CRAFT ADVISORY CRITERIA.
THURSDAY...A PERIOD OF SMALL CRAFT ADVISORY CONDITIONS PROBABLE.
SOUTHERLY WIND GUSTS COULD NEAR GALE FORCE FOR A TIME LATER THURSDAY.
SOME GUSTY THUNDERSTORMS LATE IN THE AFTERNOON AND EVENING POSSIBLE.
FRIDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW SMALL CRAFT
ADVISORY CRITERIA.
RIP CURRENTS...
FOR MONDAY, WINDS BECOME NORTHWEST 10-20 MPH WITH A CONTINUED
MEDIUM SOUTHERLY SWELL OF 6-7 SECONDS. WITH BREAKING WAVES 2
FEET OR LESS, HAVE GONE WITH A LOW RISK FOR THE DEVELOPMENT OF
DANGEROUS RIP CURRENTS AT ALL BEACHES.
FOR TUESDAY, WINDS START NORTHERLY BEFORE SHIFTING SOUTHEASTERLY,
BUT ONLY AT AROUND 5 MPH WITH A CONTINUED MEDIUM SOUTHERLY
SWELL OF 6-7 SECONDS. WITH BREAKING WAVES 2 FEET OR LESS, HAVE
GONE WITH A LOW RISK FOR THE DEVELOPMENT OF DANGEROUS RIP
CURRENTS AT ALL BEACHES.
FOR SPECIFIC BEACH FORECASTS, VISIT WEATHER.GOV/BEACH/PHI
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT EARLY THIS MORNING FOR
ANZ430-431-450>454.
DISCUSSION...DESILVA/FITZSIMMONS/GORSE/HOEFLICH
AVIATION...DESILVA/FITZSIMMONS/GORSE
MARINE...FITZSIMMONS/GORSE
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