693
FXUS61 KPHI 290013
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
813 PM EDT FRI MAR 28 2025
SYNOPSIS
A STRONG WARM FRONT WILL LIFT NORTH ACROSS THE REGION TONIGHT.
THE FRONT WILL STALL OVER NEW ENGLAND SATURDAY, THEN SLIDE BACK
SOUTHWESTWARD INTO THE REGION AS A COLD FRONT SATURDAY NIGHT. IT
WILL STALL ACROSS THE AREA ON SUNDAY. THIS FRONT FINALLY LIFTS
BACK TO THE NORTHEAST ONCE AND FOR ALL SUNDAY NIGHT INTO EARLY
MONDAY, BEFORE A MORE POWERFUL FRONT MOVES INTO THE REGION FROM
THE NORTHWEST LATE MONDAY AND MONDAY NIGHT. HIGH PRESSURE RETURNS
TUESDAY AND WEDNESDAY BEFORE ANOTHER SYSTEM APPROACHES FOR THURSDAY
INTO FRIDAY.
NEAR TERM /THROUGH SATURDAY/
A BATCH OF LIGHT RAIN SHOWERS ASSOCIATED WITH THE WARM FRONT IS
CROSSING EASTERN PENNSYLVANIA AND NEW JERSEY AT THIS TIME. RADAR
IS ALSO SHOWING MORE SHOWERS (A BIT MORE INTENSE) ACROSS NORTHERN
PA WHICH ARE TRACKING ESE. WE HAVE ADJUSTED POPS/WX GRIDS TO ACCOUNT
FOR THESE RECENT CHANGES. POPS ACROSS THE NORTH WILL REMAIN HIGHER/LONGER
SINCE THE SECOND BATCH OF SHOWERS WILL ARRIVE THERE A LITTLE BEFORE
MIDNIGHT. ANY ADJUSTMENTS TO OTHER GRIDS (TEMPS, WINDS, SKY) WERE
RATHER MINOR.
WARM FRONT STALLS TO OUR NORTHEAST ON SATURDAY, BUT STILL FAR
ENOUGH AWAY TO ENVELOPE OUR WHOLE REGION IN A TRULY WARM AIR
MASS. HIGHS REGION WIDE, EXCEPT IN THE HIGHER ELEVATIONS AND
NEAR THE COOLER MARINE WATERS, SHOULD BE CLOSE TO IF NOT ABOVE
80 DEGREES FOR THE FIRST TIME THIS YEAR. THE LAST TIME PHILLY
HIT 80 WAS NOVEMBER 6TH. SOME GUIDANCE DOES SUGGEST SOME SHOWERS
COULD POP UP CLOSE TO WHERE THE FRONT STALLS DURING THE
AFTERNOON, SO HAVE SOME CHANCE POPS IN NORTHWESTERN NJ TOMORROW
AFTERNOON. ASIDE FROM THE WARMTH, IT WILL BE QUITE BREEZY, WITH
SOUTHWEST WINDS SUSTAINED UP TO 15 MPH WITH GUSTS UP TO 30 MPH.
WITH THE WARMTH, THIS POSES A FIRE WX RISK...SEE FIRE WEATHER
SECTION BELOW.
SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/
BACKDOOR COLD FRONT LOOKS TO SLIP SOUTHWESTWARD BACK ACROSS THE
REGION SATURDAY NIGHT INTO SUNDAY AS STRONGER HIGH PRESSURE
BUILDS OVER SOUTHEASTERN CANADA. NOT EXPECTING MUCH IF ANY
PRECIP WITH IT, BUT CERTAINLY A CHANCE OF A FEW SHOWERS OR SOME
SPOTTY DRIZZLE/MIST. A SOUTHWEST-NORTHEAST GRADIENT IN LOWS IS
EXPECTED SATURDAY NIGHT, WITH DELMARVA NOT DROPPING FAR BELOW 60
WHILE THE POCONOS AND NORTHERN NJ DROP INTO THE MID 40S.
FRONT STALLS ACROSS THE CWA ON SUNDAY, MAKING FOR A HIGHLY
UNCERTAIN TEMPERATURE FORECAST. RIGHT NOW WHAT WE HAVE IS THE
BEST CHANCE GIVEN LATEST GUIDANCE, BUT SHOULD THE FRONT MEANDER
OR MAKE BETTER OR WORSE PROGRESS SATURDAY NIGHT THAN CURRENTLY
ANTICIPATED, THESE READINGS COULD BE QUITE A BIT OFF. OTHERWISE,
MOST FORCING ON SUNDAY STAYS OFF TO THE NORTH AND WEST, SO ONLY
A SMALL CHANCE OF ANY SHOWERS DURING THE DAY, WHILE CLOUDS WILL
BE MORE ABUNDANT THAN SATURDAY. HIGHS WELL INTO THE 70S FROM
PHILLY SOUTH AND WEST, BUT ONLY UPPER 50S IN PARTS OF NORTHERN
AND EASTERN NJ...AGAIN, WITH THE CAVEAT THAT UNCERTAINTY HERE IS
RATHER HIGH.
LEADING ENERGY AND WARM ADVECTION MOVING IN SUNDAY NIGHT INTO
MONDAY MORNING MAY BRING A FEW SHOWERS INTO THE REGION, BUT NOT
EXPECTING SIGNIFICANT WIDESPREAD PRECIP JUST YET. STILL, THE
INCREASING LOW LEVEL JET AHEAD OF THE NEXT STRONG COLD FRONT
SHOULD HELP PUSH THE STALLED BACKDOOR FRONT BACK TO OUR
NORTHEAST BY MIDDAY MONDAY, REESTABLISHING THE WARMTH ONCE
AGAIN, THOUGH NOT QUITE AS WARM AS SATURDAY. AFTER LOWS IN THE
50S NORTHEAST AND 60S SOUTHWEST ON SUNDAY NIGHT, WIDESPREAD
HIGHS IN THE 70S ARE EXPECTED ON MONDAY.
THIS WILL OCCUR JUST AHEAD OF THE AFOREMENTIONED STRONG FRONT.
GUIDANCE HAS SLOWED THIS FEATURE A BIT, WHICH MAY HELP REDUCE
SEVERE WEATHER RISK SOMEWHAT, BUT THE DYNAMICS ARE CERTAINLY
STRONG. WE REMAIN IN A SLIGHT RISK FOR SEVERE. BEST ODDS NOW
LOOK LIKE DURING THE EVENING MONDAY, WITH THE FRONT PUSHING
THROUGH AND COOLING US DOWN OVERNIGHT. LOWS WILL FOLLOW A MORE
TRADITIONAL NORTHWEST TO SOUTHEAST GRADIENT, WITH 30S POCONOS
AND CLOSER TO 50 ALONG THE COAST.
LONG TERM /TUESDAY THROUGH FRIDAY/
HIGH PRESSURE WILL MAKE FOR A BREEZY AND MUCH COOLER DAY
TUESDAY, WITH SUNSHINE RETURNING. HIGHS MAINLY IN THE 50S. COLD
CANADIAN AIR MASS BUILDS OVERHEAD FOR TUESDAY NIGHT WITH
REDUCING WINDS, SO MOST AREAS AWAY FROM THE COAST AND MARINE
WATERS MAY BE NEAR OR BELOW FREEZING TUESDAY NIGHT. DEPENDING
ON HOW IT PLAYS OUT, MIGHT NEED FROST ADVISORIES OR FREEZE
WARNINGS FOR THE DELMARVA SOUTH OF WILMINGTON, WHERE THE GROWING
SEASON IS DEFINED TO BEGIN ON APRIL 1, THOUGH AT THIS MOMENT WE
ARE NOT FORECASTING TEMPS TO DROP QUITE THAT MUCH. WEDNESDAY
STARTS WITH SOME SUN, THEN CLOUDS INCREASE AS THE NEXT SYSTEM
APPROACHES. HIGHS AGAIN IN THE 50S FOR MOST. ONE OR MORE WAVES
OF LOW PRESSURE THEN MOVE INTO THE REGION THURSDAY AND FRIDAY
NEXT WEEK, WITH CONSIDERABLE UNCERTAINTY ON TIMING, BUT PLENTY
OF CHANCES OF CLOUDS AND RAIN. THAT SAID, GUIDANCE DOES WANT TO
LIFT A WARM FRONT NORTH OF THE REGION DURING THIS TIME, PUSHING
TEMPS BACK TOWARDS THE 70S DURING THE DAY WITH LOWS CLOSER TO 50
AT NIGHT.
AVIATION /00Z SATURDAY THROUGH WEDNESDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THROUGH OZ...VFR. A SW WIND AROUND 5-10 KNOTS. CLOUDS CONTINUE
TO INCREASE AND CEILINGS LOWER TO AROUND 5000 FEET. AROUND 23Z,
ISOLATED LIGHT SHOWERS MOVE IN FROM THE WEST. MODERATE
CONFIDENCE.
TONIGHT...GENERALLY VFR, HOWEVER, A BRIEF PERIOD OF MVFR
VISIBILITY IS POSSIBLE FROM AROUND 00Z TO 06Z IN LIGHT RAIN
SHOWERS WITH CEILINGS DROPPING TO AROUND 4000 FEET. CEILINGS
AROUND 4000 FT, LIFT QUICKLY AFTER 6Z TO OVER 10000 FEET. LLWS
IS PRESENT AT 2000 FEET FROM THE SW AT 40-50 KNOTS FROM AROUND
2Z THROUGH 12Z SATURDAY. MODERATE CONFIDENCE.
SATURDAY...VFR. WINDS INCREASE OUT OF THE SW AFTER 12Z.
SUSTAINED WINDS ARE 10-15 KNOTS WITH GUSTS 20-25 KNOTS. CEILINGS
CONTINUE TO LIFT THROUGHOUT THE DAY AND REMAIN ABOVE 10000
FEET. HIGH CONFIDENCE.
OUTLOOK...
MOSTLY VFR SATURDAY NIGHT AND SUNDAY, THOUGH BACKDOOR FRONT
COULD PRESENT LOW CIG ISSUES, WITH HIGHEST CHANCE AT KTTN.
SCATTERED SHOWERS MAY BE MORE OF AN ISSUE SUNDAY NIGHT INTO
MONDAY MORNING AS THE BACKDOOR COLD FRONT LIFTS BACK NORTH AS A
WARM FRONT, THEN WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS
WILL BE THE BIGGEST CONCERN LATE MONDAY INTO MONDAY NIGHT. VFR
TUESDAY AND WEDNESDAY.
MARINE
INCREASING SOUTH TO SOUTHWEST FLOW AS A WARM FRONT LIFTS
NORTHWARD ACROSS THE REGION TONIGHT INTO SATURDAY WILL BRING
SMALL CRAFT ADVISORY LEVEL WAVES TO THE OCEAN WATERS, WITH SEAS
POSSIBLY UP TO 7 FEET. WINDS LIKELY STAY MOSTLY BELOW 25 KTS,
HOWEVER. SEAS SHOULD DIMINISH LATER ON SATURDAY, BUT MAY REMAIN
AT MARGINAL SCA LEVELS THROUGH THE AFTERNOON ESPECIALLY ACROSS
THE NORTHERN OCEAN WATERS.
OUTLOOK...
MARGINAL SCA CONDITIONS DUE TO LINGERING WAVE HEIGHTS UP TO 5
FEET ARE POSSIBLE SATURDAY NIGHT, BUT OVERALL SHOULD BE
SUBSIDING.
MOST OF SUNDAY LOOKS SUB-SCA, BUT LATE IN THE DAY WAVE HEIGHTS
INCREASE AGAIN. SOUTHERLY WINDS ALSO INCREASE WITH GUSTS UP TO
30 KTS SUNDAY NIGHT AND MONDAY, THEN BECOME NORTHWESTERLY MONDAY
NIGHT THROUGH TUESDAY BEHIND A COLD FRONT BEFORE SUBSIDING. AN
INTERVAL OF GALES IS POSSIBLE MONDAY NIGHT OR TUESDAY BEHIND THE
FRONT. WHILE WINDS WILL DIMINISH BY TUESDAY NIGHT, SEAS MAY
REMAIN ELEVATED AT SCA LEVELS THROUGH WEDNESDAY.
FIRE WEATHER
SPOTTY SHOWERS ARE EXPECTED ACROSS THE REGION TONIGHT, BUT WETTING
RAINS ARE NOT ANTICIPATED IN MOST OF THE REGION. RAPID WARMING
AND DRYING IS EXPECTED ON SATURDAY, WITH RELATIVE HUMIDITY DROPPING
TO NEAR 30 PERCENT AS TEMPERATURES SOAR TO NEAR 80 ACROSS MUCH
OF THE REGION. GUSTY SOUTHWEST WINDS WILL ALSO REACH 30 MPH AT
TIMES. FOR THIS REASON, HAVE OPTED TO ISSUE A SPECIAL WEATHER
STATEMENT FOR FIRE SPREAD ACROSS THE REGION FOR SATURDAY.
CONDITIONS SHOULD BE LESS VOLATILE SUNDAY AS A BACKDOOR FRONT
BRINGS COOLER, MOISTURE AIR TO AT LEAST NORTHEASTERN PORTIONS OF
THE REGION, WHILE THE CHANCE OF SHOWERS WILL BE A BIT HIGHER AND
CLOUD COVER LOOKS MORE WIDESPREAD.
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT
SATURDAY FOR ANZ450>453.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 2 PM EDT
SATURDAY FOR ANZ454-455.
SYNOPSIS...RCM
NEAR TERM...OHARA/RCM
SHORT TERM...RCM
LONG TERM...RCM
AVIATION...GUZZO/RCM
MARINE...RCM
FIRE WEATHER...
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