523  
FXUS61 KCTP 151328  
AFDCTP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE STATE COLLEGE PA  
828 AM EST FRI NOV 15 2024  
   
SYNOPSIS  
 
LIGHT RAIN SHOWERS FOCUSED ACROSS THE CENTRAL MOUNTAINS AND  
SUSQUEHANNA VALLEY EARLY TODAY WILL DECREASE IN COVERAGE  
DURING THE MID TO LATE MORNING HOURS AS UPPER LEVEL LOW  
PRESSURE CONTINUES TO DRIFT SOUTHEAST ACROSS VIRGINIA AND TOWARD  
THE DELMARVA PENINSULA.  
 
DRY AND MILDER WEATHER IS ANTICIPATED FOR THE WEEKEND, WITH  
BREEZIER CONDITIONS LEADING TO AN ELEVATED WILDFIRE SPREAD RISK  
ON SATURDAY. A PASSING RAIN SHOWER WILL BE POSSIBLE ON MONDAY;  
OTHERWISE CONTINUED SEASONABLY MILD AND DRY THROUGH EARLY NEXT  
WEEK  
 
 
   
NEAR TERM /UNTIL 6 PM THIS EVENING/  
 
1012 MB, SLOWLY WEAKENING SURFACE LOW OVER THE NORTH SHORE OF  
LAKE ERIE EARLY THIS MORNING HAS A SFC TROUGH EXTENDING SSE  
THROUGH THE UPPER OHIO RIVER VALLEY AND CENTRAL APPALACHIANS TO  
A SECONDARY LOW (~1002 MB) JUST SOUTH OF THE OUTER BANKS.  
 
UPPER LEVEL LOW PRESSURE SINKING SE FROM NORTHERN VA THIS  
MORNING WILL INJECT ENERGY INTO THIS LOW CAUSING QUITE RAPID  
INTENSIFICATION, BUT LITTLE IMPACT TO OUR CWA.  
 
RIDGING ALOFT FROM THE WEST AND LLVL RIDGING FROM THE NORTH WILL  
COMBINE TO FIRST DECREASE THE MID AND UPPER LEVEL CLOUD DECK  
THEN GRADUALLY ERODE THE LOWER STRATUS/STRATOCU DECK FROM NE TO  
SW ACROSS THE REGION LATE THIS MORNING THROUGH THIS AFTERNOON.  
BUFKIT SOUNDINGS WITH HIGH MOISTURE UP THROUGH ABOUT 5 KFT AGL  
ARE MORE PESSIMISTIC THAN THE HREF/NBM APPROACH WITH RESPECT TO  
THE TIMING OF THE CLEARING TREND AND DELAY IT BY UP TO 2-3 HOURS  
AT ANY ONE LOCATION THIS AFTERNOON.  
 
THE CLOSE PROXIMITY TO THE AFOREMENTIONED SFC TROUGH WILL KEEP  
THE LOW CLOUDS LINGERING THE LONGEST ACROSS THE WESTERN MTNS OF  
PA WITH EVEN SOME DRIZZLE POSSIBLE INTO EARLY THIS AFTERNOON.  
 
TEMPS TO START THE DAY WILL RANGE FROM THE UPPER 30S TO  
LOW 40S. HIGHS THIS AFTERNOON WILL BE IN A RATHER TIGHT RANGE OF  
ONLY 5-7 DEG F - IN THE UPPER 40S (NORTHERN AND WESTERN MTNS)  
TO LOW AND MID 50S THROUGHOUT THE CENTRAL AND SOUTHERN VALLEYS.  
 
 
   
SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/  
 
LOW CLOUDS WILL LIKELY LINGER OVER THE WESTERN ALLEGHENIES AND  
LAUREL HIGHLANDS TONIGHT WITH DECREASING CLOUD COVER (SCT-BKN)  
FURTHER EAST.  
 
HIGH PRESSURE BUILDING IN FROM THE GRT LKS SHOULD SUPPLY FAIR  
WEATHER SATURDAY. HOWEVER, MODEL SOUNDINGS INDICATE LOW LEVEL  
MOISTURE TRAPPED BENEATH A SUBSIDENCE INVERSION COULD RESULT IN  
STUBBORN LOW CLOUDS THE FIRST HALF OF THE DAY WHERE THE  
NORTHWEST FLOW ASCENDS THE ALLEGHENY PLATEAU.  
 
VERTICAL MIXING UP TO BETWEEN 2.5-3 KFT AGL SATURDAY WITH  
PROGGED 900MB TEMPS OF 4-6C YIELDS HIGH TEMPS RANGING FROM  
AROUND 50F OVER THE HIGHEST ELEVATIONS OF THE N MTNS/LAURELS, TO  
AROUND 60F IN THE SUSQ VALLEY.  
 
A MODERATELY TIGHT LLVL PRESSURE GRADIENT ACCENTUATED BY LARGER  
SCALE DESCENT WITHIN THE THERMALLY INDIRECT/RIGHT EXIT REGION  
OF AN 80KT NW JET MAX WILL LEAD TO PEAK NW WIND GUSTS IN THE 25  
TO 30 MPH RANGE ON SATURDAY.  
 
POTENTIAL FOR ELEVATED TO CRITICAL FIRE WX CONDITIONS WILL  
BE THE RESULT AND A FIRE WEATHER WATCH REMAINS IN EFFECT FOR THE  
EASTERN THIRD OF THE CWA ON SATURDAY - WHICH MATCHES UP WELL  
WITH PA DCNR/BOF CATEGORICAL VERY HIGH FIRE DANGER RISK.  
 
LOOK FOR A FROSTY START TO SUNDAY WITH LOWS IN THE 25-35F  
RANGE. HIGH PRESSURE DOME MIGRATES OVER CENTRAL PA ON SUNDAY  
PROVIDING A MOSTLY SUNNY AND PLEASANT END TO THE WEEKEND WITH  
LIGHT WINDS. HIGHS IN THE MID 50S TO LOW 60S REMAIN ABOVE  
AVERAGE FOR MID NOVEMBER.  
 
 
   
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/  
 
A SUBTLE SHORTWAVE IS STILL PROGGED TO PASS NORTH OF US SUNDAY  
NIGHT INTO MONDAY MORNING. A WEAK AND MOISTURE STARVED  
COLD FRONT WILL SLIDE ACROSS THE STATE AS A RESULT, BUT GIVEN  
HOW DRY THE AIRMASS WILL BE POPS HAVE BEEN CAPPED NEAR 30% AND  
ARE ONLY PRESENT ACROSS THE NW WHERE MOISTURE WILL BE SUFFICIENT  
FOR LIGHT PRECIPITATION.  
 
SURFACE HIGH PRESSURE WILL BUILD IN ALONG WITH UPPER LEVEL  
RIDGING PROVIDING FAIR AND TRANQUIL WEATHER FOR MONDAY AFTERNOON  
BEFORE CLOUDS BEGIN BUILDING IN AGAIN FOR TUESDAY AHEAD OF A  
DIGGING UPPER LEVEL TROUGH. HIGH TEMPERATURES FOR THE MIDDLE OF  
NEXT WEEK WILL MODERATE AND BECOME 10-15 DEGREES ABOVE NORMAL  
GIVEN RELATIVELY WARM 850MB TEMPS ALOFT. ADDITIONALLY A SLIGHT  
CHANCE OF RAIN WILL PERSIST FOR TUE AND WED GIVEN THE  
UNCERTAINTY OF THE SURFACE LOWS POSITION OFF TO OUR WEST.  
 
WEDNESDAY AND BEYOND COULD BE THE FIRST SIGNAL FOR A PATTERN  
CHANGE ACROSS THE REGION TO BECOME MORE COLD AND SEASONABLE.  
STRONG HIGH PRESSURE WILL BUILD ACROSS THE WESTERN UNITED STATES  
WITH A DEEP CLOSED LOW OVER THE HIGH PLAINS THAT WILL LIKELY  
PROGRESS NORTH EASTWARD INTO THE END OF NEXT WEEK. CURRENT  
GUIDANCE HAS A DEEP SURFACE LOW SPINNING OVER THE WESTERN GREAT  
LAKES AT THE END OF NEXT WEEK WHICH COULD BRING IN OUR FIRST  
WAVE OF CONTINENTAL POLAR AIR FOR THE SEASON.  
 
 
   
AVIATION /13Z FRIDAY THROUGH TUESDAY/  
 
CONFIDENCE REMAINS HIGH (90%) IN LIFR TO IFR CONDITIONS FOR THE  
REST OF THE DAY AT JST AND BFD, WITH LOW CIGS AS WELL AS  
MORNING FOG. AOO AND UNV WILL SEE SUB IFR CONDS THROUGH AT LEAST  
17Z, AND POTENTIALLY AS LONG AS 20-23Z. THE EASTERN TERMINALS  
(IPT/MDT/LNS) WILL STAY OUT OF IFR, BUT TEMPO MVFR CIGS ARE  
POSSIBLE AT IPT AND MDT. -DZ IS EXPECTED PERIODICALLY UNTIL  
MID- MORNING AT JST/AOO/UNV. CROSS-LAKE FLOW THEN REINFORCES THE  
LOW LEVEL MOISTURE FRI NIGHT, AND COULD EVEN TAKE IPT BACK TO  
MVFR AFTER 08Z SAT.  
 
THE NW WIND ABOVE THE SUBSIDENCE INVERSION INCREASES AGAIN FRI  
EVENING AND LASTS INTO MID-DAY SAT, BRINGING ABOUT SOME WEAK  
LLWS LATE FRI NIGHT INTO EARLY SAT. THE SIGNAL IS STRONGEST  
OVER THE SRN, ESP 2 SERN TERMINALS, WHERE A TIGHT GRADIENT  
DEVELOPS BETWEEN THE DEPARTING LOW AND THE HIGH MOVING IN FROM  
THE WEST. SAT AFTN SFC GUSTS INTO THE M20S AT MDT AND LNS. MVFR  
CIGS STAY IN FOR THE NW UNTIL SAT AM, THEN IMPROVE TO VFR  
(EVERYWHERE) AS HIGH PRESSURE FLOATS OVERHEAD.  
 
OUTLOOK...  
 
SUN...IFR BFD/JST EARLY. IMPROVEMENT TO VFR FOR ALL TERMINALS  
THROUGH THE DAY.  
 
SUN PM-MON AM...CFROPA. MVFR CIGS/VIS IN -SHRA, MAINLY N HALF.  
 
MON PM-TUES...NW FLOW. IFR/MVFR CIGS NW, VFR SE.  
 
 
   
FIRE WEATHER  
 
A FAIRLY TIGHT PRESSURE GRADIENT BETWEEN THE UPSTREAM HIGH AND  
LOW PRESSURE OVER THE CANADIAN MARITIMES SHOULD RESULT IN WIND  
GUSTS SAT AFTERNOON IN THE 20-30 MPH RANGE OVER THE EASTERN  
PART OF THE FORECAST AREA PER LATEST BUFKIT SOUNDINGS. THE  
WINDS, COMBINED WITH RH VALUES DIPPING TO NEAR 30PCT AND VERY  
DRY FINE FUELS, WILL LIKELY RESULT IN AN ELEVATED RISK OF  
WILDFIRE SPREAD.  
 
 
   
CTP WATCHES/WARNINGS/ADVISORIES  
 
FIRE WEATHER WATCH FROM SATURDAY MORNING THROUGH SATURDAY  
AFTERNOON FOR PAZ051>053-057>059-066.  
 
 
 
 
 
SYNOPSIS...LAMBERT/BAUCO  
NEAR TERM...LAMBERT/BAUCO  
SHORT TERM...LAMBERT/BAUCO  
LONG TERM...BOWEN  
AVIATION...DANGELO/COLBERT  
FIRE WEATHER...FITZGERALD/STEINBUGL  
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