105  
FXUS61 KPHI 290735  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
335 AM EDT SAT MAR 29 2025  
   
SYNOPSIS  
 
A WARM FRONT WILL STALL OVER NEW ENGLAND TODAY, THEN SLIDE BACK  
SOUTHWESTWARD INTO THE REGION AS A COLD FRONT TONIGHT. 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 MONDAY NIGHT. HIGH PRESSURE RETURNS TUESDAY AND  
WEDNESDAY BEFORE ANOTHER SYSTEM APPROACHES FOR THURSDAY INTO  
FRIDAY.  
 
 
   
NEAR TERM /THROUGH TONIGHT/  
 
THE WARMEST DAY SO FAR THIS YEAR IS EXPECTED TODAY, WITH  
TEMPERATURES CLIMBING TO NEAR 80 DEGREES FOR MUCH OF THE REGION  
THIS AFTERNOON. BREEZY AND DRY WITH PERIODS OF CLOUDS AND SUN.  
 
UPPER RIDGING WILL BUILD FROM THE WEST TODAY THROUGH TONIGHT.  
AT THE SURFACE, HIGH PRESSURE WILL REMAIN CENTERED NEAR BERMUDA.  
A FRONTAL BOUNDARY WILL BE STALLED TO THE NORTH OF OUR AREA,  
PUSHING SOUTHWEST INTO NEW JERSEY AND SOUTHEAST PENNSYLVANIA  
INTO TONIGHT BEFORE STALLING OUT LOCALLY.  
 
THE MAIN STORY TODAY WILL BE THE UNSEASONABLE WARMTH ACROSS THE  
REGION. MODEST WSW FLOW WITHIN A VAST, DRY SUBTROPICAL AIRMASS  
WITH 850 MB TEMPERATURES NEAR 10C TO 13C WILL SUPPORT SURFACE  
TEMPERATURES CLIMBING QUICKLY INTO THE 70S BY AFTERNOON.  
FORECAST AFTERNOON HIGHS ARE MOSTLY IN THE UPPER 70S TO LOW 80S  
FOR MOST AREAS. EVEN THE IMMEDIATE COASTAL AREAS SHOULD WARM UP  
QUITE WELL BY MIDDAY BEFORE ANY MARINE INFLUENCE TAKES HOLD INTO  
THE AFTERNOON. DELAWARE BEACHES AND THE NEW JERSEY SHORE AREAS  
NORTH OF SEASIDE HEIGHTS WILL HAVE A SHOT AT REACHING 80 DEGREES  
GIVEN THE STRONG OFFSHORE WSW WINDS. FOR IBSP/LBI AND SOUTH  
(BARRIER ISLANDS) IN NEW JERSEY, THE SEA BREEZE WILL PROBABLY  
START INCHING INLAND A BIT INTO THE AFTERNOON, BUT TEMPERATURES  
SHOULD STILL CLIMB TO AT LEAST NEAR 70 DEGREES IN THOSE AREAS  
TOO. THE HIGHER ELEVATIONS IN OUR NORTHWEST ZONES SHOULD TOP OUT  
IN THE LOW TO MID 70S TOO.  
 
WHILE IT WILL BE QUITE WARM FOR LATE MARCH STANDARDS, IT WILL  
ALSO BE BREEZY AND DRY. SO IT SHOULD BE A RELATIVELY COMFORTABLE  
WARMTH. WE SHOULD BE SAFE FROM RECORDS, AS THIS DATE IN 1945  
EXPERIENCED SOME VERY IMPRESSIVE TEMPERATURES IN THE MID TO  
UPPER 80S AT MOST SITES. DAILY RECORD HIGHS HAVE BEEN INCLUDED  
IN THE CLIMATE SECTION BELOW. WSW WINDS WILL INCREASE TO AROUND  
10-20 MPH, WITH GUSTS NEAR 25-35 MPH. THE STRONGER WINDS AND  
GUSTS WILL BE MAINLY FROM AROUND THE I-95 CORRIDOR AND  
NORTH/WEST OF THERE. CLOUDS WILL BE VARIABLE IN NATURE, WITH  
PERIODS OF MOSTLY CLOUDY AND MOSTLY SUNNY SKIES. THE CLOUDS WILL  
BE A LIMITING FACTOR IN TEMPERATURES OVER ACHEIVING FORECAST  
VALUES.  
 
THE FRONTAL BOUNDARY WILL RETURN SOUTHWEST INTO OUR AREA AS A  
BACKDOOR COLD FRONT BEGINNING IN THE EVENING. GUIDANCE VARIES ON  
EXACTLY WHERE IT WILL STALL OUT OVERNIGHT, BUT THE GENERAL  
CONSENSUS IS FOR THIS TO BE SOMEWHERE AROUND A LINE FROM  
ATLANTIC CITY TO THE PHILLY METRO TO THE LEHIGH VALLEY OR BERKS  
COUNTY. NORTHEAST OF THE FRONTAL BOUNDARY, TEMPERATURES WILL  
FALL INTO THE 40S AND LOW 50S TONIGHT WITH ENE WINDS, LOW  
CLOUDS, AND PERHAPS SOME AREAS OF FOG OR DRIZZLE DEVELOPING  
LATE. SOUTHWEST OF THE BOUNDARY, WILL MAINTAIN THE SOUTHWEST  
FLOW WITH TEMPERATURES GRADUALLY FALLING TO THE MID 50S TO NEAR  
60 DEGREES OVERNIGHT. MOSTLY CLOUDY SOUTHWEST OF THE BOUNDARY AS  
WELL WITH PLENTY OF MID LEVELS CLOUDS AROUND.  
 
TONIGHT WILL BE DRY FOR MOST AREAS. THE EXCEPTION (ASIDE FROM  
ANY POTENTIAL DRIZZLE) WILL BE THE POTENTIAL FOR SOME SHOWERS  
AND THUNDERSTORMS DEVELOPING NEAR AND NORTH OF I-80 CORRIDOR AS  
A WEAK WAVE PASSES TO THE NORTH.  
 
 
   
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/  
 
FRONT STALLS ACROSS THE CWA ON SUNDAY, MAKING FOR AN UNCERTAIN  
TEMPERATURE FORECAST. RIGHT NOW WHAT WE HAVE IS THE BEST CHANCE  
GIVEN LATEST GUIDANCE BUT SHOULD THE FRONT END UP A BIT FARTHER  
NORTH OR SOUTH THAN CURRENTLY FORECAST, 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  
WILL BE WELL INTO THE 70S FROM PHILLY SOUTH AND WEST BUT ONLY  
UPPER 50S TO LOW 60S 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  
WILL 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 LOW 50S  
NORTHEAST AND LOW 60S SOUTHWEST ON SUNDAY NIGHT, WIDESPREAD  
HIGHS IN THE 70S ARE EXPECTED ON MONDAY.  
 
A STRONG COLD FRONT WILL APPROACH THE AREA LATE DAY MONDAY.  
FORECAST GUIDANCE CONTINUES TO FAVOR A SOMEWHAT LATER ARRIVAL  
TIME OF THE FRONT COMPARED TO EARLIER THINKING WITH IT LIKELY  
ARRIVING SOMETIME IN THE LATE EVENING OR OVERNIGHT HOURS. THAT  
SAID, THERE IS STILL SOME UNCERTAINTY ON THIS TIMING. SHOWERS  
AND STORMS ARE EXPECTED AHEAD OF THE FRONT WITH POPS RAMPING UP  
ACROSS THE AREA BEGINNING LATE AFTERNOON WITH THE HIGHEST  
CHANCES OCCURRING DURING THE EVENING TIMEFRAME. CAPE DOES NOT  
LOOK TO BE TERRIBLY IMPRESSIVE HOWEVER THERE WILL BE VERY STRONG  
DYNAMICS AND SHEAR SO THE AREA REMAINS IN A SLIGHT RISK OF  
SEVERE WEATHER FROM THE STORM PREDICTION CENTER. ALSO WORTH  
NOTING, PWATS WILL BE MAXING OUT AROUND 1.5 INCHES WHICH IS NEAR  
THE CLIMATOLOGICAL MAX FOR THIS TIME OF YEAR SO THERE WILL ALSO  
BE THE THREAT FOR HEAVY RAINFALL AND EVEN SOME POSSIBLE  
LOCALIZED FLOODING. ONCE THE COLD FRONT PUSHES THROUGH,  
OVERNIGHT LOWS WILL COOL DOWN INTO THE 40S WITH EVEN SOME 30S  
OVER THE POCONOS AND NW NJ.  
 
 
   
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 PARTIAL SUN, THEN CLOUDS INCREASE AS THE NEXT  
SYSTEM APPROACHES. HIGHS AGAIN IN THE 50S FOR MOST. MULTIPLE  
WAVES OF LOW PRESSURE LOOK TO THEN MOVE THROUGH THE AREA LATER  
NEXT WEEK IN THE THURSDAY THROUGH SATURDAY TIMEFRAME. WHILE  
THERE IS UNCERTAINTY REGARDING THE DETAILS, THE GENERAL TREND  
WILL BE FOR IT TO BECOME MORE UNSETTLED WITH PLENTY OF CHANCES  
FOR CLOUDS AND RAIN DURING THIS TIMEFRAME. TEMPERATURES,  
HOWEVER, WILL BE WARMING WITH HIGHS IN THE 60S AND 70S THROUGH  
THIS PERIOD.  
 
 
   
AVIATION /07Z SATURDAY THROUGH WEDNESDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
THROUGH 15Z...VFR CONDITIONS. SOUTH TO SOUTHWEST WINDS  
INCREASING TO NEAR 5-10 KTS. LLWS WITH WINDS NEAR 2KFT AROUND 40  
KTS FROM THE SOUTHWEST. HIGH CONFIDENCE.  
 
TODAY...VFR WITH VARIABLE CLOUDS. WSW WINDS INCREASING TO 10-20  
KTS WITH GUSTS NEAR 25-30 KTS. HIGH CONFIDENCE.  
 
TONIGHT...INITIALLY VFR. MVFR CEILINGS WILL PUSH INLAND, LIKELY  
IMPACTING MOST TERMINALS BY 06-09Z. RDG, ILG, AND MIV COULD  
STAY VFR FOR THE PERIOD HOWEVER. INITIALLY SW WINDS 5-10 KTS  
WILL SHIFT ENE WHEN AND WHERE LOW CEILINGS ARRIVE. MODERATE  
CONFIDENCE ON THE OVERALL FORECAST PROGRESSION, BUT LOWER  
CONFIDENCE ON EXACT TIMING OF MVFR CEILINGS ARRIVING.  
 
OUTLOOK...  
 
MOSTLY VFR 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 WITH RESTRICTIONS  
LIKELY. VFR TUESDAY AND WEDNESDAY.  
 
 
   
MARINE  
 
ADVISORY CONDITIONS DEVELOPING ACROSS THE ATLANTIC COASTAL  
WATERS THIS MORNING INTO THE AFTERNOON. SOUTHWEST WINDS  
INCREASING TO 15-20 KTS, WITH SOME NEARSHORE GUSTS NEAR 25 KTS  
POSSIBLE FOR ALL COASTAL WATERS, INCLUDING DELAWARE BAY. HAVE  
HELD OFF ON EXPANDING THE CURRENT SMALL CRAFT ADVISORY TO THE  
BAY FOR NOW, HOWEVER WOULD NOT BE SURPRISED IF THIS IS WARRANTED  
IN A FUTURE UPDATE IF 25 KT GUSTS MATERIALIZE NEARSHORE. SEAS  
BUILDING TO 3-6 FEET ACROSS THE ATLANTIC WATERS. SEAS AND WINDS  
DIMINSHING INTO THE EVENING.  
 
A BACKDOOR COLD FRONT WILL PUSH SOUTHWEST FROM SOUTHERN NEW  
ENGLAND AND LONG ISLAND THIS EVENING, WHICH WILL SHIFT WINDS  
FROM SOUTHWEST TO NORTHEAST AROUND 10-15 KTS FOR AREAS MAINLY  
NORTH OF ATLANTIC CITY. THIS AREA WILL ALSO HAVE POTENTIAL FOR  
FOG AND DRIZZLE DEVELOPMENT, WHICH COULD LOWER VISIBILITY TO  
NEAR 1 NM AT TIMES.  
 
OUTLOOK...  
 
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.  
WHILE WINDS WILL DIMINISH BY TUESDAY NIGHT, SEAS MAY REMAIN  
ELEVATED AT SCA LEVELS THROUGH WEDNESDAY.  
 
 
   
FIRE WEATHER  
 
CONDITIONS WILL BE NEAR CRITICAL FIRE WEATHER THRESHOLDS TODAY.  
WSW WINDS INCREASING TO 10-20 MPH, WITH GUSTS OF 25-35 MPH  
POSSIBLE. THIS WILL BE COMBINED WITH MINIMUM RELATIVE HUMIDITY  
VALUES NEAR 30-35% AND TEMPERATURES CLIMBING INTO THE UPPER 70S  
TO LOW 80S IN MOST AREAS. THE SPECIAL WEATHER STATEMENT FOR  
INCREASED RISK OF RAPID FIRE SPREAD WILL REMAIN IN EFFECT  
THROUGH TODAY.  
 
CONDITIONS SHOULD BE LESS VOLATILE SUNDAY AS A BACKDOOR FRONT  
BRINGS SLIGHTLY COOLER AND MORE HUMID 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.  
MINIMUM RELATIVE HUMIDITY WILL BE NEAR 50%.  
 
 
   
PHI WATCHES/WARNINGS/ADVISORIES  
 
PA...NONE.  
NJ...NONE.  
DE...NONE.  
MD...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR  
ANZ450>453.  
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ454-  
455.  
 
 
 
 
 
SYNOPSIS...FITZSIMMONS/RCM  
NEAR TERM...STAARMANN  
SHORT TERM...FITZSIMMONS/RCM  
LONG TERM...FITZSIMMONS/RCM  
AVIATION...FITZSIMMONS/STAARMANN  
MARINE...FITZSIMMONS/STAARMANN  
FIRE WEATHER...STAARMANN  
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