265  
FXUS61 KPHI 090252  
AFDPHI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ  
952 PM EST FRI NOV 8 2024  
   
SYNOPSIS
 
 
A COLD FRONT CROSSES THE AREA TONIGHT, THEN HIGH PRESSURE WELL  
TO THE NORTHWEST BUILDS IN DURING SATURDAY BEFORE SHIFTING  
OFFSHORE SUNDAY. A WARM FRONT LIFTS NORTH OF OUR AREA SUNDAY  
AFTERNOON, THEN A COLD FRONT CROSSES THE AREA MONDAY. HIGH  
PRESSURE BUILDS IN FOR THE MIDDLE OF NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH SATURDAY/
 
 
WE ARE WATCHING THE COLD FRONT CROSS THE AREA THIS EVENING AS  
WINDS SHIFT TO NW AND GUST 20 TO 30 KTS AS IT MOVES THRU. THE  
GUSTY WINDS (AT LOWER SPEEDS) WILL CONTINUE FOR A FEW HOURS  
ONCE THE FRONT MOVES THRU. TEMPERATURES WILL FALL MORE SHARPLY  
FOLLOWING THE FROPA. JUST SOME ADJUSTMENTS TO WINDS/TEMPS FOR  
THE UPDATE. NO PRECIP WITH THE FRONT (OR EVEN CLOUDS!)  
 
FAIR WEATHER WILL CONTINUE DURING THE NEAR TERM AS HIGH  
PRESSURE ACROSS THE UPPER GREAT LAKES REGION GRADUALLY BUILDS  
TOWARDS THE MIDDLE ATLANTIC. SKIES WILL REMAIN CLEAR TONIGHT AND  
SUNNY ON SATURDAY. IT'LL BE SEASONABLY COLD TONIGHT AND  
NOTICEABLY COLDER SATURDAY (COMPARED TO FRIDAY). LOWS TONIGHT  
WILL FAVOR THE LOW 40S FOR THE METRO/SUBURBAN AREAS AND 30S  
ELSEWHERE. TOMORROW, INSTEAD OF HIGHS IN THE UPPER 60S AND LOW  
70S LIKE TODAY, READINGS WILL FAVOR THE 50S. WINDS WILL REMAIN  
WEST TO NORTHWEST AT AROUND 5 MPH TONIGHT AND TURN MORE NORTH ON  
SATURDAY AT AROUND 10 MPH.  
 

 
   
SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/
 
 
THE AREA WILL LIE BENEATH AN UPPER LEVEL RIDGE ON SATURDAY  
NIGHT WITH THE RIDGE AXIS SLIDING OFFSHORE ON SUNDAY. AS THIS  
OCCURS, AN UPPER LEVEL TROUGH WILL LIFT ACROSS THE GREAT LAKES  
AND OVER THE NORTHEAST US ON SUNDAY NIGHT INTO MONDAY. AT THE  
SURFACE, HIGH PRESSURE WILL LIE OVERHEAD ON SATURDAY NIGHT  
BEFORE SHIFTING OFFSHORE ON SUNDAY. A WEAK WARM FRONT WILL LIFT  
NORTH OF THE AREA ON SUNDAY WITH A COLD FRONTAL PASSAGE OCCURING  
ON MONDAY.  
 
WITH THIS BEING SAID, ANOTHER DRY AND SEASONABLY COOL NIGHT IS  
IN STORE FOR SATURDAY NIGHT. THANKS TO LIGHT WINDS AND CLEAR  
SKIES, AN EFFICIENT RADIATIONAL COOLING NIGHT LOOKS TO OCCUR.  
HOWEVER, THE TRANQUIL WEATHER WILL BE SHORT-LIVED AS SKIES  
BECOME MORE CLOUD- FILLED DURING THE DAY ON SUNDAY AS OUR NEXT  
WEATHER SYSTEM APPROACHES. LOW PRESSURE WILL BE TRACKING ACROSS  
THE NORTHERN GREAT LAKES REGION ON SUNDAY AND ACROSS SOUTHERN  
ONTARIO/QUEBEC ON SUNDAY NIGHT AND MONDAY. ASSOCIATED WITH THIS  
LOW WILL BE A TRAILING COLD FRONT WHICH IS EXPECTED TO CROSS  
THROUGH THE REGION ON MONDAY. BELIEVE IT OR NOT, PERIODS OF  
LIGHT RAIN CERTAINLY LOOK PLAUSIBLE AS SOME MOISTURE ASSOCIATED  
WITH HURRICANE RAFAEL OVER THE GULF OF MEXICO WILL BE DRAWN  
NORTHWARD INTO THE MID-ATLANTIC REGION. THIS WILL BRING SOME  
BENEFICIAL RAINFALL TO THE REGION BEGINNING LATE SUNDAY INTO  
SUNDAY NIGHT WITH POPS AROUND 90% IN MOST AREAS. AS THE COLD  
FRONT CROSSES THROUGH THE REGION ON MONDAY, RAIN IS EXPECTED TO  
END FROM WEST TO EAST BY MONDAY MORNING. A FEW LINGERING SHOWERS  
MAY HANG UP ALONG THE COAST, BUT OVERALL SHOULD LEAD TO A DRY  
DAY BY MONDAY AFTERNOON. IN TERMS OF TOTAL RAINFALL, WE ARE  
EXPECTING ROUGHLY 0.25-0.50 INCHES OF RAIN AREAWIDE. ALTHOUGH,  
THIS CERTAINLY WILL NOT BE ENOUGH TO BREAK THE ONGOING DROUGHT  
CONDITIONS, IT WILL DEFINITELY BE APPRECIABLE CONSIDERING HOW  
DRY IT HAS BEEN OVER THE LAST 2 MONTHS.  
 
IN TERMS OF TEMPERATURES FOR THE PERIOD, WE ARE LOOKING AT  
HIGHS IN THE UPPER 50S TO MID 60S ON SUNDAY WITH MID 60S TO LOW  
70S ON MONDAY. LOWS WILL MAINLY BE IN THE UPPER 20S TO MID 30S  
ON SATURDAY NIGHT WITH A MUCH MILDER NIGHT ON SUNDAY NIGHT  
EXPECTED WITH LOWS ONLY IN THE UPPER 40S TO MID 50S.  
 

 
   
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
 
 
THE LONG TERM FORECAST REMAINS LARGELY UNCHANGED HOWEVER, THERE  
REMAINS SOME UNCERTAINTY WITH WHAT MAY OCCUR LATE IN THE WEEK.  
 
CYCLONIC FLOW IS FORECAST TO REMAIN IN PLACE TUESDAY BEFORE  
UPPER- LEVEL RIDGING ARRIVES ON WEDNESDAY. THE NEXT UPPER-LEVEL  
TROUGH IS THEN PROGGED TO APPROACH LATE WEDNESDAY INTO THURSDAY,  
WHILE BECOMING NEGATIVELY TILTED AND/OR CUTTING OFF BY FRIDAY.  
AT THE SURFACE, A SECONDARY COLD FRONT WILL ARRIVE ON TUESDAY  
AHEAD OF HIGH PRESSURE LATER TUESDAY INTO WEDNESDAY. A COLD  
FRONT THEN ARRIVES WITH POSSIBLE COAST LOW DEVELOPMENT LATER  
THURSDAY INTO FRIDAY.  
 
SO FOR RIGHT NOW, EXPECT DRY AND MOSTLY SEASONABLE CONDITIONS  
TO OCCUR MONDAY NIGHT THROUGH WEDNESDAY. BY WEDNESDAY NIGHT AND  
THROUGH THE END OF THE WEEK, WE'LL NEED TO MONITOR HOW THE UPPER  
LEVEL PATTERN EVOLVES OVER THE NEXT SEVERAL DAYS AS THIS PLAYS  
A BIG FACTOR ON WHAT WILL OCCUR LATER IN THE WEEK. ALL MAJOR  
GLOBAL GUIDANCE SUGGEST THAT THERE WILL POSSIBLY BE SOME SORT OF  
COASTAL LOW DEVELOPING ALONG THE MID-ATLANTIC COAST. THE GFS IS  
MOST AGGRESSIVE WITH THIS SCENARIO, DEVELOPING A STRONG COASTAL  
LOW MOVING UP INTO NEW ENGLAND. THE ECMWF AND CMC ARE MUCH  
WEAKER WITH THIS SCENARIO, BUT BOTH DO INCLUDE SOME SORT OF  
CYCLOGENESIS OFF THE MID-ATLANTIC. IT IS WORTH MONITORING  
NONETHELESS, AS THIS WILL LIKELY BRING ANOTHER PERIOD OF RAINY  
WEATHER TO THE AREA LATE NEXT WEEK.  
 

 
   
AVIATION /03Z SATURDAY THROUGH WEDNESDAY/
 
 
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,  
KILG, KMIV, KACY AND SURROUNDING AREAS.  
 
REST OF TONIGHT... VFR. CLEAR SKIES. WEST WINDS SHIFTING TO  
NORTHWEST AND GUSTING TO AROUND 20 TO 25 KTS WITH A FRONTAL  
PASSAGE THEN MOSTLY 10 TO 12 KTS OVERNIGHT. HIGH CONFID.  
 
SATURDAY... VFR. MOSTLY SUNNY SKIES. NORTH WINDS INCREASING TO  
AROUND 10 KNOTS BY LATE MORNING. HIGH CONFID.  
 
OUTLOOK...  
 
SATURDAY NIGHT...VFR. NO SIGNIFICANT WEATHER EXPECTED.  
 
SUNDAY THROUGH SUNDAY NIGHT...VFR FOR MOST OF SUNDAY, WITH SUB-  
VFR LIKELY ON SUNDAY NIGHT. PERIODS OF LIGHT RAIN LIKELY.  
 
MONDAY THROUGH WEDNESDAY...VFR. NO SIGNIFICANT WEATHER  
EXPECTED.  
 

 
   
MARINE
 
 
A SCA FLAG TONIGHT AS COLD AIR ADVECTION AND A DECENT PRESSURE  
GRADIENT AHEAD OF THE BUILDING HIGH ACROSS THE WATERS. NORTHWEST  
WINDS WITH GUSTS OF 25 TO 30 KNOTS ARE EXPECTED OVERNIGHT WHILE  
SEAS BUILD TO 4 TO 5 FT ON THE OCEAN. THE SEAS ACROSS DELAWARE  
BAY WILL BECOME CHOPPY OVERNIGHT. FAIR WEATHER. WINDS AND SEAS  
DECREASE SATURDAY, SO THE SCA FLAG WILL BE DOWN FOR THE DAY.  
WINDS WILL BE MOSTLY FROM THE NORTH AT 10 TO 15 KTS.  
 
OUTLOOK...  
 
SATURDAY NIGHT...NO MARINE HEADLINES EXPECTED.  
 
SUNDAY THROUGH MONDAY...A PERIOD OF SCA CONDITIONS IS LIKELY  
BEGINNING LATE SUNDAY AFTERNOON INTO MONDAY MORNING WITH GUSTS  
UP TO 25-30 KTS AND SEAS AROUND 4-5 FEET.  
 
MONDAY NIGHT THROUGH WEDNESDAY...NO MARINE HEADLINES EXPECTED.  
 

 
   
FIRE WEATHER
 
 
VERY DRY CONDITIONS CONTINUEM, BUT RH'S HAVE COME UP ABOVE RED  
FLAG CRITERIA. WINDS ARE KICKING UP WITH THE PASSING COLD FRONT  
BUT SHOULD DIMINISH AGAIN OVERNIGHT.  
 
FOR SATURDAY, A VERY DRY AIR MASS WILL BE IN PLACE WITH DEW  
POINTS DOWN INTO THE UPPER TEENS TO LOWER 20S. DAYTIME MINIMUM  
RELATIVE HUMIDITY VALUES ARE FORECAST TO BE IN THE 20-30 PERCENT  
RANGE. NORTHERLY WINDS 10-15 MPH SHOULD DIMINISH SOME DURING  
THE AFTERNOON. ALTHOUGH THE WINDS ARE LIGHTER COMPARED TO  
FRIDAY, THE CONDITIONS CONTINUE TO BE VERY DRY AND THUS AN  
ELEVATED RISK FOR FIRE SPREAD REMAINS. AN SPS WILL LIKELY BE  
ISSUED THIS EVENING AFTER THE RED FLAG WARNING COMES DOWN.  
 
SHOWERS ARE FORECAST TO RESULT IN A WETTING RAIN (0.25-0.50  
INCHES CURRENTLY FORECAST) LATER SUNDAY, ESPECIALLY AT NIGHT,  
INTO MONDAY MORNING.  
 
CONTINUE TO FOLLOW BURN RESTRICTIONS AND CHECK WITH YOUR STATE  
AND LOCAL FIRE OFFICIALS FOR MORE INFORMATION.  
 

 
   
CLIMATE
 
 
RECORD STRETCH (CONSECUTIVE DAYS) WITHOUT MEASURABLE  
PRECIPITATION:  
 
CURRENT  
SITE RECORD RECORD DATES THRU 11/7  
AC AIRPORT (ACY) 34 DAYS AUG-SEP 1995 36 DAYS  
AC MARINA (55N) 39 DAYS AUG-SEP 1995 37 DAYS  
GEORGETOWN (GED) 34 DAYS OCT-NOV 2001 41 DAYS  
PHILADELPHIA (PHL) 29 DAYS OCT-NOV 1874 40 DAYS  
TRENTON (TTN) 38 DAYS APR-MAY 1903 40 DAYS  
WILMINGTON (ILG) 34 DAYS JAN-FEB 1909 40 DAYS  
 

 
   
PHI WATCHES/WARNINGS/ADVISORIES
 
 
PA...NONE.  
NJ...NONE.  
DE...NONE.  
MD...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ430-431.  
SMALL CRAFT ADVISORY UNTIL 9 AM EST SATURDAY FOR ANZ450>455.  
 

 
 

 
 
SYNOPSIS...GORSE/OHARA  
NEAR TERM...OHARA/RCM  
SHORT TERM...DESILVA/GORSE  
LONG TERM...DESILVA/GORSE  
AVIATION...DESILVA/GORSE/OHARA/RCM  
MARINE...DESILVA/GORSE/OHARA/RCM  
FIRE WEATHER...PHI  
CLIMATE...PHI  
 
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