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FXUS61 KCTP 151817
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
117 PM EST FRI NOV 15 2024
SYNOPSIS
*GRADUAL CLEARING THROUGH TONIGHT; BEST VIEWING OF THE SUPER
BEAVER MOON & ISS FLYOVER = AREAS EAST OF THE ALLEGHENY MTNS
*DRY, BREEZY, AND MILDER START TO THE WEEKEND WITH AN ELEVATED
WILDFIRE SPREAD RISK PARTICULARLY IN EASTERN PENNSYLVANIA
*CONTINUED SEASONABLY MILD AND DRY THROUGH TUESDAY; NEXT
RAINFALL LIKELY DURING THE SECOND HALF OF NEXT WEEK
NEAR TERM /UNTIL 7 PM THIS EVENING/
VISIBLE SATELLITE TRENDS SHOW LOW CLOUDS LOCKED IN ACROSS THE
ALLEGHENIES WITH AREAS OF FOG AND DRIZZLE LATE THIS MORNING;
MEANWHILE SIGNIFICANT CLEARING IS DETECTED OVER THE EXTREME
SOUTHEASTERN PORTION OF THE FORECAST AREA PARTICULARLY IN
LANCASTER COUNTY.
ON BALANCE, THE OVERALL SKY TREND WILL BE TOWARD PARTIAL/GRADUAL
CLEARING ESPECIALLY TO THE EAST OF THE ALLEGHENY FRONT THANKS
TO A DOWNSLOPING NORTHWEST BREEZE. CONVERSELY, THE NORTHWEST
FLOW ASCENDING THE HIGHER TERRAIN FAVORS CLOUDY SKIES INTO
TONIGHT OVER THE WESTERN ALLEGHENIES AND LAUREL HIGHLANDS.
MAX TEMPS TODAY RANGE FROM THE MID 40S TO MID 50S OR NEAR TO
SLIGHTLY ABOVE (+1-5F) DAILY CLIMO.
SHORT TERM /7 PM THIS EVENING THROUGH MONDAY/
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.
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.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
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. A SLIGHT CHANCE OF RAIN
WILL PERSIST FOR TUE AND WED GIVEN THE UNCERTAINTY OF THE
SURFACE LOWS POSITION OFF TO OUR WEST. IN SPITE OF THE RAIN
CHANCES, IT MAY BE A GOOD IDEA TO CONSIDER TAKING CARE OF ANY
LINGERING OUTDOOR PROJECTS (YARDWORK, HOLIDAY DECORATIONS, ETC.)
PRIOR TO A BIG PATTERN CHANGE THAT WILL ARRIVE LATER WEDNESDAY.
BY LATER WEDNESDAY, CONFIDENCE CONTINUES TO INCREASE IN A
PATTERN FLIP FOR THE EASTERN US. STRONG HIGH PRESSURE WILL
BUILD ACROSS THE WESTERN UNITED STATES WITH A DEEP CLOSED LOW
OVER THE HIGH PLAINS THAT IS PROGGED TO MOVE INTO THE NORTHEAST
SOMETIME IN THE LATER WEDNESDAY - EARLY THURSDAY TIMEFRAME.
LATEST GUIDANCE KEEPS THE SWIRLING UPPER LOW OVER THE GREAT
LAKES REGION INTO AT LEAST THE FIRST HALF OF THE WEEKEND. SUCH A
PATTERN WOULD SUPPORT TEMPERATURES TRENDING COOLER THAN NORMAL
FOR THE FIRST TIME IN AWHILE WITH A TRUE CONTINENTAL POLAR
AIRMASS MOVING INTO THE REGION. PREVAILING NORTHWEST FLOW OVER
THE ANOMALOUSLY WARM GREAT LAKES WATERS WOULD SUPPORT LAKE
EFFECT/UPSLOPE SNOW SHOWERS IN THE TYPICAL FAVORED REGIONS OF
WESTERN AND NORTHERN PA.
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
CONFIDENCE REMAINS HIGH (90%) IN LIFR TO IFR CONDITIONS FOR THE
REST OF THE DAY AT JST AND BFD. MAIN QUESTION IS HOW LONG THE
1/4 SM VSBY REMAINS AT JST. WINDS HAVE VEERED AROUND TO BECOME
NW, WHICH MAY HELP THE VSBY TREND UP TO A MILE OR MORE BY 19-20Z,
BUT CAN'T RULE OUT THAT LOWER VSBY CONTINUES THROUGH MUCH OF
THE DAY WITH CIGS BEING SO LOW.
CIGS AT UNV REMAIN IFR, WITH LOW END MVFR / HIGH END IFR AT AOO.
EXPECT THESE CONDITIONS TO CONTINUE THROUGH 20-23Z BEFORE SLIGHT
IMPROVEMENT. THE EASTERN TERMINALS (IPT/MDT/LNS) WILL STAY OUT
OF IFR, BUT TEMPO MVFR CIGS ARE LIKELY AT IPT, MDT, AND LNS.
FLOW OFF THE GREAT LAKES WILL REINFORCE THE LOW LEVEL MOISTURE
TONIGHT, AND COULD TAKE IPT, MDT, AND LNS BACK TO MVFR AFTER
07Z SAT (LOWER CHANCES TOWARDS THE SOUTHEAST).
THE NW WIND ABOVE THE SUBSIDENCE INVERSION WILL INCREASE THIS
EVENING, BRINGING ABOUT SOME WEAK LLWS LATE TONIGHT INTO EARLY
SAT. THE SIGNAL IS STRONGEST OVER MDT/LNS, WHERE A TIGHT
GRADIENT DEVELOPS BETWEEN THE DEPARTING LOW AND THE HIGH MOVING
IN FROM THE WEST. LOW LEVEL SHEAR WILL DISSIPATE SAT MORNING AS
TURBULENT EDDIES BRING WIND GUSTS DOWN TO THE SFC. EXPECT SAT
AFTN SFC GUSTS INTO THE M20S AT MDT AND LNS. CIGS WILL REMAIN
MVFR IN THE NW SAT AM, THEN FINALLY IMPROVE TO VFR AT JST AND
BFD AROUND 17-20Z SAT.
OUTLOOK...
SUN...MAINLY VFR.
SUN NIGHT - EARLY MON...CFROPA. MVFR CIGS/VIS IN -SHRA, MAINLY
N HALF.
MON PM-TUES...NW FLOW. IFR/MVFR CIGS NW, VFR SE.
WED...RESTRICTIONS POSS, MAINLY NW. MORE WIDESPREAD RESTRICTIONS
WITH RAIN AND LLWS WED NIGHT.
FIRE WEATHER
ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS REMAIN POSSIBLE
SATURDAY (MID MORNING THROUGH THE AFTERNOON) OVER THE EASTERN
PORTION OF CENTRAL PENNSYLVANIA DUE TO A COMBINATION OF GUSTY
WINDS 25-35 MPH FROM THE NORTHWEST, LOW RELATIVE HUMIDITY
(25-35%) AND DRY FUELS.
CTP WATCHES/WARNINGS/ADVISORIES
FIRE WEATHER WATCH FROM SATURDAY MORNING THROUGH SATURDAY
AFTERNOON FOR PAZ051>053-057>059-066.
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...LAMBERT/BAUCO
LONG TERM...BANGHOFF/BOWEN
AVIATION...DANGELO/COLBERT
FIRE WEATHER...STEINBUGL
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