405  
FXUS61 KPHI 111007  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
607 AM EDT SAT OCT 11 2025  
   
SYNOPSIS  
 
HIGH PRESSURE WILL CONTINUE TO MOVE FURTHER OFFSHORE TODAY. A  
COASTAL STORM WILL THEN AFFECT THE REGION TONIGHT THROUGH EARLY  
NEXT WEEK BRINGING SIGNIFICANT IMPACTS TO PARTS OF OUR AREA.  
IMPROVING CONDITIONS EXPECTED BY TUESDAY AS THE STORM WEAKENS  
AND MOVES OUT TO SEA. HIGH PRESSURE WILL BEGIN BUILDING BACK  
INTO THE REGION DURING THE MIDDLE TO END OF NEXT WEEK.  
 
 
   
NEAR TERM /THROUGH TONIGHT/  
 
LATEST ANALYSIS DEPICTS HIGH PRESSURE EAST OF CAPE COD,  
CONTINUING EASTWARD INTO TO THE ATLANTIC. ONE LOW PRESSURE IS  
DEVELOPING JUST EAST OF FLORIDA, HEADING NORTH, WHILE ANOTHER IS  
OVER LAKE HURON, HEADING SOUTHEAST. BOTH SURFACE LOWS ARE  
ACCOMPANIED BY CLOSED UPPER LEVEL LOWS, WITH THE NORTHERN ONE  
BEING NOTABLY STRONGER AT PRESENT, WITH AN UPPER RIDGE ALIGNED  
NORTH-SOUTH FROM JUST EAST OF CAPE COD SOUTHWARD INTO THE OPEN  
ATLANTIC.  
 
THROUGH THE NEXT 24 HOURS, THE TWO UPPER LEVEL LOW PRESSURE  
SYSTEMS WILL CONTINUE MOVING IN THEIR RESPECTIVE DIRECTIONS,  
BUT THEIR MOTION WILL SLOW CONSIDERABLY, RESULTING IN THE  
SOUTHERN ONE BEING NEAR THE SOUTH CAROLINA COAST AND THE  
NORTHERN ONE BEING OVER UPSTATE NEW YORK IN 24 HOURS. THE  
SURFACE LOW FOR THE NORTHERN SYSTEM WILL WASH OUT AS ENERGY  
BEGINS TO TRANSFER TO A NEW SURFACE LOW DEVELOPING OFF THE  
ATLANTIC COAST, WHILE THE SOUTHERN LOW WILL HEAD TOWARDS THE  
SOUTH CAROLINA/NORTH CAROLINA BORDER. THE BOTTOM LINE FROM ALL  
THIS IS THAT WHILE THE EASTERLY WIND WILL START TO INCREASE,  
CLOUDS WILL BECOME MORE DOMINANT, AND THE CHANCE OF RAIN WILL  
ALSO BE INCREASING THROUGH THE NEXT 24 HOURS, THE MAIN SHOW  
STILL LOOKS TO BE BEYOND THE NEAR-TERM PERIOD, DESPITE A SLOW  
BUT STEADY TREND TOWARDS MORE UNPLEASANT CONDITIONS. SHOWER  
CHANCES DURING THE DAY TODAY STILL LOOK RELATIVELY LOW, BELOW 50  
PERCENT OVERALL, AND WHILE ODDS DO INCREASE DURING THE NIGHT  
TONIGHT, WIDESPREAD RAIN ACROSS THE ENTIRE REGION STILL LIKELY  
WON'T ARRIVE IN THE NEXT 24 HOURS, WITH RAIN TONIGHT BEING A BIT  
MORE PATCHY AND ALSO CONCENTRATED ON SOUTHERN PARTS OF THE  
FORECAST REGION.  
 
THE WARM ADVECTION ALOFT AHEAD OF THESE TWO SYSTEMS SHOULD HELP  
ELEVATE HIGHS A BIT TODAY DESPITE THE INCREASED CLOUD COVER AND  
SPOTTY SHOWERS, MAINLY IN THE MID-UPPER 60S, WITH LOW 70S IN THE  
FAR SOUTH. LOWS TONIGHT WON'T DROP MUCH WITH THE ONSHORE FLOW,  
CLOUDS AND INCREASING RAIN COVERAGE, WITH 60S FAR SOUTH, MID-  
UPPER 50S MOST OTHER AREAS, EXCEPT NEAR 50 POCONOS AND NW NJ.  
 
 
   
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/  
 
***SIGNIFICANT IMPACTS POSSIBLE FROM A STRONG COASTAL STORM  
SUNDAY THROUGH MONDAY***  
 
OVERVIEW: WE CONTINUE TO CLOSELY MONITOR THE POTENTIALLY  
SIGNIFICANT COASTAL STORM THAT IS EXPECTED TO DEVELOP NEAR THE  
NORTH CAROLINA COAST ALONG A STALLED FRONT BEGINNING TODAY. THIS  
STORM IS ANTICIPATED TO STRENGTHEN AND LIFT NORTHWARD SUNDAY  
INTO EARLY NEXT WEEK. THE PRIMARY IMPACTS WILL BE FROM COASTAL  
FLOODING, BEACH EROSION, DUNE BREACHING, STRONG TO POTENTIALLY  
DAMAGING WINDS, AND HEAVY RAIN. THE HEAVIEST RAINFALL AND  
STRONGEST WINDS ARE STILL ANTICIPATED TO BE NEAR THE ATLANTIC  
COAST.  
 
WHAT HAS CHANGED: LATEST DETERMINISTIC MODEL GUIDANCE HAS  
TRENDED WEAKER AND EAST WITH A MORE ELONGATED LOW PRESSURE  
SYSTEM COMPARED TO PREVIOUS FORECASTS. WHAT THIS MEANS IS THAT  
THE QPF FORECAST HAS BEEN LOWERED. EVEN WITH THIS CURRENT TREND,  
COASTAL IMPACTS ARE STILL EXPECTED TO BE SIGNIFICANT. ALSO,  
WITH THESE RUN TO RUN VARIATIONS OF THE DETERMINISTIC GUIDANCE,  
IT IS IMPORTANT TO LOOK AT THE ENSEMBLES GUIDANCE WHICH DOES  
STILL HAVE BOTH OUTCOMES OF A STRONGER AND MORE WEST PLACEMENT  
OF THE LOW ALONG WITH THE WEAKER EASTWARD LOW. DUE TO THIS  
SPREAD AND UNCERTAINTY, NOT TOO MANY CHANGES WERE MADE OVERALL  
ASIDE FROM THE QPF FORECAST. GUIDANCE WILL LIKELY CONTINUE TO  
STRUGGLE AND VARY FROM RUN TO RUN WITH THIS SYSTEM UNTIL IT  
ACTUALLY FORMS A WELL DEFINED LOW PRESSURE CENTER SOMETIME TODAY  
OR TONIGHT. OUR MARINE HAZARDS WERE UPGRADED DUE TO CONSISTENT  
CONFIDENCE FOR GALE TO STORM WARNING CRITERIA BEING MET. THERE  
IS MORE UNCERTAINTY FOR THE HIGH WIND WATCH, SO THAT REMAINS  
UNCHANGED AT THIS TIME.  
 
COASTAL STORM FORECAST DETAILS...  
 
THE PERIOD SUNDAY THROUGH MONDAY WILL BE WHEN OUR AREA LIKELY  
EXPERIENCES THE BRUNT OF THE IMPACTS FROM THE COASTAL STORM.  
RIGHT NOW, WINDS ARE EXPECTED TO BE SUSTAINED AT 15-25 MPH  
INLAND AND 30- 40 MPH AT THE COAST. FOR WIND GUSTS, 30-40 MPH  
FOR INLAND AREAS WITH 50-60 MPH ALONG THE COAST. SUNDAY MORNING  
THROUGH MONDAY IS WHEN THE STRONGEST WINDS ARE EXPECTED. DUE TO  
THE UNCERTAINTY IN THE INTENSITY AND FORECAST TRACK OF THE  
COASTAL STORM, THERE WERE NO CHANGES MADE TO THE HIGH WIND WATCH  
WITH THIS UPDATE AS MENTIONED ABOVE. REGARDLESS, POWER OUTAGES  
AND TREE DAMAGE ARE POSSIBLE, ESPECIALLY TOWARD THE COAST.  
 
IN ADDITION TO THE WIND, HEAVY RAIN IS FORECAST, AND A MARGINAL  
(1/4) RISK EXCESSIVE RAINFALL OUTLOOK IS IN PLACE FOR THE  
SOUTHERN HALF OF DELMARVA AND MAINLY THE COASTAL AREAS OF NEW  
JERSEY FOR SUNDAY THROUGH SUNDAY NIGHT. A WIDESPREAD 1-2 INCHES  
OF RAIN IS FORECAST ACROSS OUR ENTIRE AREA, WITH LOCALLY HIGHER  
AMOUNTS OF 2-3 INCHES POSSIBLE, ESPECIALLY NEAR THE COAST. THESE  
TOTALS HAVE LOWERED COMPARED TO PREVIOUS FORECASTS DUE TO MODEL  
TRENDS. NOW, THIS MAY SEEM LIKE A LOT OF RAIN, BUT IT IS  
IMPORTANT TO KEEP IN MIND THAT THIS WILL BE FALLING OVER A 48-60  
HOUR PERIOD. IT HAS ALSO BEEN QUITE DRY. GIVEN THIS FORECAST,  
THE THINKING IS THAT FLOODING DUE TO HEAVY RAIN ALONE WILL BE  
LIMITED TO POOR DRAINAGE AND URBAN AREAS. HOWEVER, THIS RAINFALL  
COULD EXACERBATE IMPACTS NEAR THE COAST WITH MODERATE AND  
POTENTIALLY MAJOR COASTAL FLOODING ONGOING. SIGNIFICANT HIGH  
TIDES ARE EXPECTED DUE TO STRONG NORTHEAST WINDS RESULTING IN  
WATER PILING UP ALONG THE COAST.  
 
THE SETUP IS OVERALL VERY COMPLEX. THE SURFACE LOW WILL BE  
DEVELOPING OVER THE GULF STREAM ALONG A STALLED BOUNDARY, AND  
ITS NORTHWARD MOVEMENT WILL DEPEND ON HOW IT INTERACTS WITH A  
SURFACE HIGH OVER NOVA SCOTIA, AN UPPER LEVEL LOW OVER THE GREAT  
LAKES, AND EVEN DISTANT TROPICAL STORM JERRY. THE EXTENT AND  
SEVERITY OF IMPACTS IN OUR AREA WILL BE DIRECTLY RELATED TO THE  
EXACT TRACK AND EVOLUTION OF THE LOW PRESSURE CENTER. STAY TUNED  
TO THE LATEST BRIEFING PACKAGES AND FORECAST UPDATES AS THE  
FORECAST CONTINUES TO EVOLVE AND DETAILS BECOME MORE APPARENT  
OVER THE NEXT 24 HOURS.  
 
 
   
LONG TERM /TUESDAY THROUGH FRIDAY/  
 
THE EARLY WEEK COASTAL STORM WILL BE WEAKENING SIGNIFICANTLY BY  
TUESDAY, BUT IT'S REMNANT LOW COULD STILL LINGER IN THE  
VICINITY OF THE COAST YIELDING A CHANCE OF SHOWERS AND SOMEWHAT  
BREEZY CONDITIONS. THE LOW WILL EVENTUALLY WEAKEN AND PUSH OUT  
TO SEA BY TUESDAY NIGHT. THEREAFTER, BROAD AND RELATIVELY WEAK  
HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES REGION. ITS  
COOLER AIRMASS WILL ARRIVE TOWARD THE END OF THE WEEK, WITH  
BELOW NORMAL TEMPERATURES AND FAIR WEATHER ANTICIPATED FOR  
THURSDAY AND FRIDAY.  
 
 
   
AVIATION /10Z SATURDAY THROUGH WEDNESDAY/  
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
TODAY...MOSTLY VFR EARLY THIS MORNING LIKELY DEGRADES SLIGHTLY  
TO MVFR LATE TODAY AS A FEW SHOWERS AND LOWER CIGS OVERSPREAD  
THE REGION WELL IN ADVANCE OF AN APPROACHING COASTAL STORM.  
WINDS EAST TO NORTHEAST 10-15 KTS, STRONGER AT KACY. MODERATE  
CONFIDENCE.  
 
TONIGHT...RAIN BECOMES MORE PREDOMINATE BY LATE TONIGHT WITH  
MVFR CONDITIONS LIKELY AT TIMES. WINDS WILL ALSO INCREASE CLOSER  
TO 20 KTS, HIGHER AT KACY. MODERATE CONFIDENCE.  
 
OUTLOOK...  
SUNDAY THROUGH MONDAY...MVFR TO IFR CONDITIONS EXPECTED WITH  
MODERATE TO HEAVY RAIN MOVING THROUGH AND GUSTY WINDS. NORTHEAST  
WIND GUSTS NEAR 45 KT POSSIBLE AT KACY. GUSTS OUT OF THE  
NORTHEAST AROUND 25-35 KT EXPECTED AT THE I-95 TERMINALS AND  
KMIV, WITH 20-30 KT ANTICIPATED WITHIN THE LEHIGH VALLEY.  
 
MONDAY NIGHT...RESTRICTIONS EXPECTED WITH SHOWERS AND LOW  
CLOUDS. WIND GUSTS DIMINISH TO AROUND 15-25 KT OUT OF THE  
NORTH/NORTHEAST.  
 
TUESDAY...CONDITONS IMPROVE BUT SUB-VFR CONDITIONS POSSIBLE  
WITH LINGERING SHOWERS AND CLOUDS. WIND GUSTS COULD GET NEAR 20  
KT AT TIMES.  
 
WEDNESDAY..VFR WITH NO SIGNIFICANT WEATHER.  
 
 
   
MARINE  
 
INCREASING EASTERLY FLOW AHEAD OF AN APPROACHING COASTAL STORM,  
ALONG WITH BUILDING SEAS, WILL BRING SCA CONDITIONS TO ALL  
OCEAN WATERS BY AFTERNOON, SO HAVE EXPANDED AND EXTENDED SCA.  
SUB-SCA CONDITIONS WILL REMAIN ON THE BAY DURING DAYLIGHT TODAY.  
APPROACHING STORM WILL CAUSE BUILDING SEAS AND WINDS ACROSS ALL  
WATERS TONIGHT AND ESPECIALLY BEYOND, NECESSITATING GALE AND  
STORM WARNINGS.  
 
OUTLOOK...  
SUNDAY THROUGH MONDAY...A STORM WARNING IS IN PLACE THROUGH  
MONDAY FOR ALL MARINE ZONES EXCEPT THE UPPER DELAWARE BAY WHERE  
A GALE WARNING HAS BEEN ISSUED. NORTHEAST WINDS 35-45 KT AND  
GUSTS UP TO 50- 55 KT EXPECTED WITHIN THE ATLANTIC COASTAL  
WATERS AND MOUTH OF DELAWARE BAY. FOR THE UPPER DELAWARE BAY,  
WINDS 25-35 KT WITH GUSTS NEAR 45 KTS WHERE THE GALE WARNING IS.  
DANGEROUS SEAS UPWARD OF 15 TO 20 FEET EXPECTED. PERIODS OF  
MODERATE TO HEAVY RAIN AND SEA SPRAY RESTRICTING VISIBILITY AT  
TIMES.  
 
MONDAY NIGHT THROUGH WEDNESDAY...CONDITIONS WILL BEGIN TO  
IMPROVE AS THE STORM WEAKENS AND BEGINS TO MOVE AWAY. HOWEVER,  
GALE FORCE WINDS MAY LINGER THROUGH TUESDAY AND ELEVATED SEAS  
ABOVE 5 FEET MAY LINGER THROUGH WEDNESDAY.  
 
 
   
TIDES/COASTAL FLOODING  
 
MINOR COASTAL FLOODING IS FORECAST WITH THIS MORNING'S HIGH  
TIDE, MAINLY FOR ATLANTIC, CAPE MAY, AND CUMBERLAND COUNTIES IN  
NJ AND SUSSEX AND KENT COUNTIES IN DE. AS A RESULT, THE COASTAL  
FLOOD ADVISORY REMAINS IN EFFECT. AS WATER LEVELS WILL START  
BUILDING THEREAFTER, CONTINUED ADVISORY INTO EARLY SUNDAY EVEN  
THOUGH SOME AREAS MAY NOT QUITE REACH ADVISORY LEVELS ON  
TONIGHT'S CYCLE.  
 
MEANWHILE, THERE IS AN INCREASING RISK OF MODERATE TO MAJOR  
COASTAL FLOODING IMPACTS BEGINNING SUNDAY THROUGH MONDAY AS A  
STRONG COASTAL STORM IMPACTS THE REGION. GUIDANCE STILL VARIES  
IN POTENTIAL OUTCOMES OF THIS STORM WITH REGARD TO SEVERITY OF  
COASTAL FLOOD IMPACTS LOCALLY, HOWEVER WE REMAIN VERY CONCERNED  
ABOUT THE POTENTIAL FOR SIGNIFICANT IMPACTS FROM THIS STORM  
ALONG OUR COASTS. AT THIS TIME, THE GREATEST THREAT OF IMPACTS  
ARE ANTICIPATED TO OCCUR ALONG THE ATLANTIC COASTS OF NEW JERSEY  
AND DELAWARE, AND DELAWARE BAY. CONFIDENCE HAS INCREASED ENOUGH  
SUCH THAT WE'VE UPGRADED THE COASTAL FLOOD WATCH TO A WARNING  
SUNDAY THROUGH MONDAY.  
 
SEVERE BEACH EROSION AND DUNE BREACHING ARE POSSIBLE ALONG THE  
ENTIRE NEW JERSEY SHORE AND FOR DELAWARE BEACHES DUE TO THE VERY  
HIGH SURF CONDITIONS THAT ARE EXPECTED. INTERESTS ALONG THE  
ATLANTIC COAST, DELAWARE BAY, BACK BAYS, AND TIDAL WATERWAYS  
SHOULD REMAIN ALERT FOR FORECAST UPDATES REGARDING THIS  
POTENTIALLY SIGNIFICANT COASTAL FLOOD EVENT.  
 
 
   
PHI WATCHES/WARNINGS/ADVISORIES  
 
PA...COASTAL FLOOD ADVISORY FROM 2 PM SUNDAY TO 11 PM EDT MONDAY  
FOR PAZ070-071-106.  
NJ...COASTAL FLOOD WARNING FROM 11 AM SUNDAY TO 9 PM EDT MONDAY FOR  
NJZ016.  
COASTAL FLOOD ADVISORY UNTIL 8 AM EDT SUNDAY FOR NJZ021>025.  
COASTAL FLOOD WARNING FROM 8 AM SUNDAY TO 8 PM EDT MONDAY FOR  
NJZ012>014-020>027.  
HIGH WIND WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT  
FOR NJZ013-014-020-022>027.  
COASTAL FLOOD ADVISORY FROM 2 PM SUNDAY TO 11 PM EDT MONDAY  
FOR NJZ017>019.  
DE...COASTAL FLOOD WARNING FROM 11 AM SUNDAY TO 9 PM EDT MONDAY FOR  
DEZ001.  
COASTAL FLOOD ADVISORY UNTIL 8 AM EDT SUNDAY FOR DEZ002>004.  
COASTAL FLOOD WARNING FROM 8 AM SUNDAY TO 8 PM EDT MONDAY FOR  
DEZ002>004.  
HIGH WIND WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT  
FOR DEZ003-004.  
MD...NONE.  
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 8 PM EDT MONDAY FOR  
ANZ430.  
STORM WARNING FROM 6 PM THIS EVENING TO 8 PM EDT MONDAY FOR  
ANZ431-450>455.  
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 PM EDT THIS EVENING  
FOR ANZ450.  
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR  
ANZ451>455.  
 
 
 
 
 
SYNOPSIS...GUZZO/RCM  
NEAR TERM...RCM  
SHORT TERM...GUZZO  
LONG TERM...GUZZO  
AVIATION...GUZZO/RCM  
MARINE...GUZZO/RCM  
TIDES/COASTAL FLOODING...  
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