344
FXUS61 KPHI 061915
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
315 PM EDT SUN JUL 6 2025
SYNOPSIS
HIGH PRESSURE WILL RETREAT OFFSHORE TODAY, RESULTING IN
INCREASING HUMIDITY. BERMUDA HIGH PRESSURE WILL THEN REMAIN IN
PLACE THROUGH THE UPCOMING WEEK. CHANTAL'S REMNANTS WILL PASS TO
OUR SOUTH LATE MONDAY, THEN A FEW ADDITIONAL WEAK SYSTEMS WILL
IMPACT THE REGION THROUGH THE REMAINDER OF THE WEEK.
NEAR TERM /THROUGH MONDAY/
TONIGHT
WE'LL START THE PERIOD WITH A SOME SCATTERED SHOWERS AND
TSTMS ACROSS THE EASTERN SHORE OF MD AND DELAWARE WHICH WILL ONLY
LAST UNTIL AROUND SUNSET BEFORE DIMINISHING. THESE ARE THE RESULT OF
THE INCREASING HUMIDITY AND DAYTIME WARMTH ALONG WITH A MINOR
SHORTWAVE MOVING IN FROM THE SOUTH. A COUPLE DOWNPOURS ARE POSSIBLE.
WE'LL CONTINUE WITH THE CHANCE POPS FOR THE PERIOD.
IT'LL BECOME INCREASINGLY HUMID OVERNIGHT AND TEMPERATURES WILL BE
SEASONABLY WARM WITH LOWS ONLY DROPPING BELOW 70 DEGREES ACROSS THE
FAR N/W AREAS. LOW CLOUDS WILL MOVE IN TOWARDS DAWN WHILE SOME LIGHT
FOG COULD DEVELOP TOO. LIGHT S TO SE EXPECTED.
MONDAY
THE INFLUENCE OF (THE REMNANTS OF) CHANTAL ARRIVE MONDAY
WITH DEEPER MOISTURE ALONG WITH MORE UPPER SHORTWAVES AND DECENT
INSTABILITY. WE EXPECT INCREASING CHANCES FOR SHOWERS AND SCATTERED
TSTMS AS THE MORNING PROGRESSES AND INTO THE AFTERNOON. DOWNPOURS
AND LOCALIZED FLOODING ARE EXPECTED. THE OVERALL COVERAGE OF
FLOODING IS EXPECTED TO BE SMALL AND LIKELY RESTRICTED TO DELMARVA
AND PERHAPS SOUTH NJ. THERE MAY BE A FEW HIGH RAINFALL TOTALS (OVER
2 INCHES) BUT THE OVERALL SPEED OF THE SYSTEM SHOULD KEEP MOST
REPORTS IN THE 1 TO 2 INCH RANGE FOR THE S/E AREAS. THESE ALSO COULD
BE A FEW STRONG GUSTS TOO WITH ISOLATED SEVERE WEATHER POSSIBLE.
WE'LL INCLUDE THE POSSIBLE HAZARDS IN THE NEXT BRIEFING PACKAGE WHICH
WILL BE ISSUED LATER TODAY.
THE LATEST FCST HAS HIGH TEMPS ON MONDAY A DEGREE OR TWO COOLER THAN
YESTERDAY. THIS ALONG WITH THE HIGHER DEW POINTS WILL KEEP APPARENT
TEMPS JUST SHORT OF HEAT ADVISORY CRITERIA.
SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/
THE OVERALL ATMOSPHERIC SETUP FOR MONDAY NIGHT THROUGH TUESDAY NIGHT
IS A CONTINUATION OF MONDAY. COVERAGE OF SHOWERS AND THUNDERSTORMS
WILL BE ISOLATED MONDAY NIGHT BEFORE COVERAGE PICKS BACK UP DURING
THE DAY TUESDAY. A COLD FRONT WILL BE SINKING SOUTHWARD MONDAY NIGHT
BUT DOES NOT ACTUALLY START TO FULLY MOVE INTO THE AREA UNTIL
TUESDAY AND STALLS OUT ACROSS THE SOUTHERN HALF OF THE AREA BY
TUESDAY NIGHT OR WEDNESDAY MORNING.
DURING THE DAY TUESDAY, THE COVERAGE OF SHOWERS AND
THUNDERSTORMS INCREASES AS THE COLD FRONT SINKING SOUTHWARD
ACTS AS AN INCREASING TRIGGER MECHANISM TO AN ALREADY CONDUCIVE
ENVIRONMENT FOR DIURNALLY DRIVEN CONVECTION. WE WILL BE WELL
INTO A TROPICAL AIR MASS WITH TEMPERATURES REACHING THE MID 80S
TO MID 90S AND DEW POINTS WILL BE WELL INTO THE 70S. THIS MEANS
HEAT INDEX VALUES WILL NEAR 100 DEGREES FOR THE URBAN CORRIDOR,
SOUTHERN NEW JERSEY, AND DELMARVA. A HEAT ADVISORY MIGHT BE
NEEDED FOR THE URBAN CORRIDOR IF THE TREND CONTINUES. THIS
ENVIRONMENT WILL SUPPORT GROWING INSTABILITY. MLCAPE VALUES ARE
UPWARDS OF 2000-3000 J/KG BUT SHEAR WILL BE ON THE LOWER SIDE.
AS A RESULT, THE POTENTIAL IS THERE FOR ISOLATED SEVERE
THUNDERSTORMS WITH WATER LOADED DOWNDRAFTS LEADING TO THE
PRIMARY CONCERN BEING DAMAGING WIND GUSTS. OUR WHOLE AREA IS IN
A MARGINAL (1/5) RISK FOR SEVERE WEATHER FOR THIS EXACT REASON.
ANOTHER CONCERN IS THE LOCALIZED FLASH FLOODING THREAT. FORECAST
SOUNDINGS ON TUESDAY SHOW A PRIME HEAVY RAIN PROFILE WITH TALL
SKINNY CAPE, PWAT VALUES OF 2-2.3 INCHES WITH OCCASIONAL PERIODS OF
2.5 INCHES, A SUITABLE WARM CLOUD LAYER DEPTH, AND THE POTENTIAL FOR
TRAINING SHOWERS AND STORMS THAT WILL BE SUFFICIENT RAINFALL
PRODUCERS. OUR WHOLE AREA IS IN A MARGINAL (1/4) RISK IN THE
EXCESSIVE RAINFALL OUTLOOK FOR THE RISK OF LOCALIZED FLASH FLOODING.
BY TUESDAY NIGHT, THE COVERAGE BECOMES MORE ISOLATED AS THE
DIURNALLY DRIVEN CONVECTION STARTS TO DIMINISH BUT THE COLD
FRONT DOES STALL OVER THE SOUTHERN PORTION OF OUR AREA.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
WE STAY UNSETTLED INTO THE LONG TERM WITH THE COLD FRONT STAYING
STALLED ACROSS THE AREA AND MULTIPLE DISTURBANCES MOVING THROUGH. ON
WEDNESDAY, THERE WILL BE ISOLATED SHOWERS AND THUNDERSTORMS AROUND
BUT THERE IS THE POTENTIAL FOR SOME MORE SCATTERED COVERAGE NEAR THE
STALLED FRONT LOCATED CLOSE TO DELMARVA AND SOUTHERN NEW JERSEY AS
THIS FRONT MIGHT ACT AS A FOCAL POINT TO ENHANCE THE DAYTIME
CONVECTION. ON THURSDAY AND FRIDAY, A WEAK DISTURBANCE LOOKS TO MOVE
THROUGH WHICH WILL LEAD TO SCATTERED SHOWERS AND THUNDERSTORMS BOTH
DAYS. ANOTHER WEAK DISTURBANCE MOVES IN FOR SATURDAY KEEPING SHOWERS
AND THUNDERSTORMS GOING.
DURING THE SECOND HALF OF THE WEEK AND INTO THE BEGINNING OF THE
WEEKEND, HIGH TEMPERATURES WILL BE MAINLY IN THE 80S. DEW POINTS
WILL REMAIN IN THE 60S AND 70S, SO WE CONTINUE TO HOLD ONTO THE
HUMIDITY.
AVIATION /19Z SUNDAY THROUGH FRIDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF TODAY...VFR. SOUTH TO SOUTHWEST AND INCREASING TO 5-10
KT. HIGH CONFIDENCE.
TONIGHT... VFR MUCH OF THE NIGHT BUT THEN IFR OR LOW-END MVFR
CIGS ARRIVE AS LOW LEVEL WINDS TURN MORE ONSHORE. LIGHT FOG
POSSIBLE TOO. LIGHT S/SE WINDS. MEDIUM CONFID OVERALL.
MONDAY... IFR OR LOW-END MVFR CONDITIONS EARLY THEN MIXING OUT
TO VFR 14Z/15Z MOST SPOTS. CHANCE OF SHOWERS/TSTMS AFTER 16Z
MOST AREAS INTO THE AFTERNOON. VCSH AND PROB30 USED FOR THE
ENDING PERIODS OF THE TAFS. SOUTH TO SOUTHWEST WINDS INCREASING
TO 10 TO 15 KTS. MEDIUM CONFID OVERALL.
OUTLOOK...
MONDAY THROUGH FRIDAY...PREVAILING VFR WITH DAILY CHANCES FOR
THUNDERSTORMS, ESPECIALLY IN THE AFTERNOON AND EVENING HOURS.
AREAS OF FOG POSSIBLE AT NIGHT.
MARINE
WINDS AND SEAS WILL REMAIN BELOW SCA LEVELS TONIGHT AND INTO MONDAY.
WINDS AND SEAS DO INCREASE MONDAY AFTERNOON AND COME UP JUST SHORT
OF SCA LEVELS. WE'LL HOLD ON ANY FLAG ATTM. ISOLATED SHOWERS/TSTMS
INTO THE EARLY EVENING FOR DELAWARE BAY AND DELAWARE COASTAL WATERS
TODAY THEN MORE SCATTERED SHOWERS/TSTMS MONDAY AFTERNOON/EVENING. AS
ALWAYS, HIGHER WINDS AND SEAS LOCALLY NEAR TSTMS.
OUTLOOK...
MONDAY THROUGH FRIDAY...WIND AND SEAS ARE FORECAST TO REMAIN
BELOW ADVISORY CRITERIA. DAILY CHANCES OF SHOWERS AND
THUNDERSTORMS, OTHERWISE FAIR WEATHER.
RIP CURRENTS...
FOR TODAY, SOUTHERLY WINDS WILL REMAIN 5-10 MPH. BREAKING WAVE
HEIGHTS OF 1-2 FEET WITH A PRIMARY SE SWELL AROUND 2 FEET AND A
6-8 SECOND PERIOD. THERE DO APPEAR TO BE SOME LONGER PERIOD
SWELLS SETTING UP AT 44009 THIS MORNING, WITH OBS SHOWING THE
DOMINANT PERIOD AS OF 3AM AROUND 16 SECONDS. HOWEVER THE
DOMINATE SWELL IS BETWEEN 1.5-2 FEET SO WE'LL OPT TO STAY WITH
LOW FOR DANGEROUS RIP CURRENTS FOR ALL BEACHES TODAY.
FOR MONDAY, SOUTHERLY WINDS WILL INCREASE TO 10-15 MPH.
BREAKING WAVE HEIGHTS INCREASE TO 2-3 FEET WITH A PRIMARY S
SWELL AROUND 3 FEET AND A 6-8 SECOND PERIOD. GIVEN SLIGHTLY
STRONGER WINDS AND SLIGHTLY HIGHER WAVES WITH SLIGHTLY HIGHER
SWELL, WENT WITH MODERATE AT THE MORE SOUTHERLY FACING NJ
BEACHES OF CAPE MAY, ATLANTIC AND OCEAN, AND LOW FOR THE
EASTERLY FACING BEACHES OF MONMOUTH AND DE.
RIP CURRENTS OCCUR OFTEN IN THE VICINITIES OF JETTIES AND PIERS
AND THE SPEED OF THE CURRENTS ARE GENERALLY MAXIMIZED AT LOW
TIDES.
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
SYNOPSIS...GUZZO/STAARMANN
NEAR TERM...OHARA
SHORT TERM...GUZZO
LONG TERM...GUZZO
AVIATION...GUZZO/OHARA/STAARMANN
MARINE...GUZZO/OHARA/STAARMANN
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