Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 021527
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1127 AM EDT THU OCT 2 2014

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL BE DISPLACED BY A STRONG COLD FRONT
WHICH WILL SWEEP ACROSS THE REGION FRIDAY NIGHT. A DEEP UPPER
LEVEL TROUGH WILL THEN REMAIN PARKED OVER THE UPPER GREAT LAKES
AND NORTHEASTERN CONUS THROUGH EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
FOG HAS LIFTED AND SKY IS NOW A MASH OF 4 OR 5 DIFFERENT
TYPES/LEVELS OF CLOUDS. THE MIXING SHOULD CONTINUE TO WORK IT OUT
TO LEAVE MAINLY DIURNAL CU IN SHORT ORDER. TEMPS ARE...AS
EXPECTED...A LITTLE BEHIND THE NORMAL DIURNAL CURVE DUE TO THE LOW
CLOUDS...BUT ARE CATCHING UP AND SHOULD MEET THE CURR FCST MAXES.
THE CU SHOULD BEGIN TO DISSIPATE BEFORE SUNSET...AND MANY AREAS
COULD BE CLEAR BY SUNSET. THERE IS JUST THE TINIEST CHANCE FOR ONE
OF THE CU TO BECOME A LOW-TOPPED OVERACHIEVER AND CAUSE A VERY BRIEF
SHOWER THIS AFTN...BUT NOT ENOUGH OF A CHC OR POTENTIAL OF AREAL
COVERAGE TO BE SO GREAT AS TO SUGGEST ANY AREA WHERE SUCH A THING
MAY OCCUR.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY NIGHT/...
SFC RIDGE EXTENDING FROM THE CANADIAN MARITIMES SWRD ALONG THE E
COAST WILL KEEP CENTRAL PA DRY TONIGHT. HOWEVER...MOIST SERLY FLOW
COMBINED WITH RADIATIONAL COOLING OF BLYR SHOULD ONCE AGAIN LEAD
TO DEVELOPING STRATUS ACROSS CENTRAL PA LATE TONIGHT. HIGHER THAN
NORMAL DWPTS WILL LEAD TO A MILD NIGHT FOR EARLY OCTOBER WITH LOWS
MOSTLY IN THE L/M50S.

MDLS HAVE COME IN LINE WITH TIMING OF STRONG COLD FRONT FRIDAY
NIGHT. DEEP SOUTHERLY FLOW IN ADVANCE OF COLD FRONT DRAWS A PLUME
OF ANOMALOUS PWATS /2-3SD ABV NORMAL IN THE 00Z GEFS/ INTO
CENTRAL PA FRI NIGHT. GIVEN THE MOISTURE AND LG SCALE FORCING
IMPLIED BY MDL 500-300 Q-VEC CONVERGENCE...HAVE RAISED POPS TO
NEAR-CERTAINTY FRIDAY NIGHT. ALL PLUME MEMBERS OF THE SREF AND
GEFS ARE INDICATING MEASURABLE RAIN FRI NIGHT.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
MDL SPREAD REMAINS LOW THRU THE WEEKEND...ALL INDICATING COLD
FRONT EXITING EASTERN PA ARND 12Z SAT. CAN/T RULE OUT LINGERING
SHRA ARND DAWN. OTHERWISE...SFC RIDGING AND ARRIVAL OF MUCH DRIER
AIR SHOULD TRANSLATE TO A DRY WEEKEND. MDL BLYR WIND FIELDS ALL
INDICATE LAKE EFFECT RAIN SHOWERS SHOULD REMAIN NORTH OF THE
BORDER...BUT HAVE KEPT A SLIGHT CHC OF SHRA OVR NW WARREN CO.

ENS MEAN 850TEMPS INDICATE THIS WILL BE THE COOLEST WX SINCE LAST
SPRING WITH MAX TEMPS FROM ONLY NEAR 50F OVR THE HIGH TERRAIN OF
THE ALLEGHENIES...TO THE L60S ACROSS THE LOWER SUSQ VALLEY. LOOKS
LIKE SFC HIGH WILL NOT PASS OVR THE REGION...SO CONDS NOT IDEAL
FOR RAD COOLING...BUT CAN/T RULE OUT FROST/FREEZE ISSUES SAT OR
SUN NIGHT OVR THE ALLEGHENIES.

INCREASING MDL SPREAD/FCST UNCERTAINTY EARLY NEXT WEEK.
HOWEVER...EXPECT A WARMING TREND AS FLOW BECOMES SOUTHERLY AHEAD
OF DIGGING TROF OVR THE GRT LKS/MIDWEST. A PERIOD OF SHOWERS
APPEARS LIKELY SOMETIME EARLY NEXT WEEK...AS UPPER TROF LIFTS
THROUGH. HOWEVER...CAN/T GO MORE THAN LOW CHC OF PRECIP ON ANY DAY
DUE TO TIMING AND STRENGTH UNCERTAINTIES.

&&

.AVIATION /15Z THURSDAY THROUGH MONDAY/...
CLOUDS HAVE BEGUN TO LIFT INTO AND SHOULD BECOME VFR-BASED CU
SHORTLY. THE CU SHOULD DISSIPATE LATE THIS AFTN AND
EVENING...LEAVING IT MAINLY CLEAR AROUND SUNSET OR SHORTLY AFTER.
THE MOIST SERLY FLOW WILL ONCE AGAIN BE LIFTED BY THE CENTRAL MTNS
TONIGHT AND LIKELY RESULT IN A RENEWAL OF THE LOW CLOUDS AND FOG
MUCH LIKE WE SAW THURS MORNING. TOTAL DECOUPLING SHOULD OCCUR THIS
EVENING AFTER AND WHILE SFC WINDS WILL BE CALM...THE INCREASING
WINDS JUST OVERHEAD WILL PROBABLY BE STRONG ENOUGH TO MAKE FOR
LLWS LATER TONIGHT AND ON FRIDAY. MIXING WILL TURN THAT DIFFERENCE
TO MORE OF A GUSTY SRLY WIND DURING THE DAY...THOUGH. THE
CLOUDS/FOG WILL ALSO TAKE A WHILE TO GO AWAY ON FRIDAY MORNING.
MIXING AND FALLING HEIGHTS COULD MAKE IT UNSTABLE ENOUGH TO MAKE A
STRAY SHOWER IN THE ALLEGHENIES BEFORE THE LARGER-SCALE FORCING
ARRIVES IN THE WEST IN THE VERY LATE AFTN/EVENING.

A VERY STRONG UPPER LEVEL TROUGH WILL DROP DOWN THROUGH THE UPPER
MIDWEST AND OHIO VALLEY ON FRIDAY...AND BRING A STRONG COLD FRONT
THROUGH FRIDAY NIGHT. THE FRONT SHOULD CLEAR THE WEST BY 09Z SAT
AND THE FAR ERN ZONES BEFORE 15Z SAT. THUNDER IS EXPECTED FRI
NIGHT. SHOWERS WILL GENERATE IN THE COLD UPSLOPE OF THE POST-
FRONTAL FLOW OVER THE N/WRN MTNS ON SAT.

OUTLOOK...

SUN-MON...MVFR CIGS PSBL NW...OTHERWISE VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO/FITZGERALD
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DANGELO/FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...DANGELO/MARTIN


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