FXUS61 KCTP 091916
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
216 PM EST WED DEC 9 2009
.SYNOPSIS...
A SHARP COLD FRONT WILL CROSS THE STATE TONIGHT...BRINGING GUSTY
WEST WINDS AND MUCH COLDER AIR BY THURSDAY MORNING. AN UNSETTLED
PATTERN WILL PERSIST OVER THE REGION INTO EARLY NEXT WEEK...
WITH STORM SYSTEMS BRINGING A CHANCE OF MIXED PRECIPITATION ON
SUNDAY...AND AGAIN ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VIGOROUS SHORTWAVE AND ASSOCIATED SHARP COLD FRONT PUSHING THRU THE
AREA LATE THIS AFTERNOON AND EVENING. INSTABILITY WEST OF THE
ALLEGHENIES IN PARTIAL TO FULL SUNSHINE EARLIER THIS AFTERNOON
HELPED TO SPROUT SOME LOW TOPPED CONVECTION WHICH TAPPED SOME
HIGHER MOMENTUM 850 MB WINDS...CAUSING WIND DAMAGE AND SOME 1 INCH
HAIL REPORTS OVER VENANGO AND WARREN COUNTIES. AREAS EAST OF THE
ALLEGHENIES HAVE BEEN COLD AIR DAMMED...AND THESE STORMS ARE
WEAKENING BUT COULD STILL SURVIVE INTO THE CENTRAL MOUNTAINS TO
PRODUCE SOME STRONG WIND GUSTS THIS EVENING.
WIND ADVISORY HEADLINES BEING CARRIED FOR ALL AREAS...WITH CENTRAL
MTNS BEGINNING AT 20Z AND THE EAST AT 22Z...THROUGH 11Z THU.
BUFKIT PROFILES SHOW THE INCREASINGLY DEEP MIXED LAYER TAPPING
50-60 KT WINDS FROM JUST A FEW THOUSAND FEET ABOVE THE SURFACE.
LAKE EFFECT TRAJECTORIES NOT LIKELY TO BRING BANDING FAR ENOUGH
SOUTH AND EAST TO IMPACT WARREN AND MCKEAN COUNTIES...BUT A SLIGHT
SHIFT WOULD BRING SOME ACCUMULATING BANDS INTO THOSE AREAS LATE
TONIGHT AND THURSDAY ESPECIALLY.
WINDS WILL BE THE MAIN STORY OVERNIGHT AND THURSDAY AS 850 MB 50KT
WINDS WILL PARTIALLY MIX TO THE SURFACE EVEN BEHIND THE CONVECTION
PRODUCING LOCAL GUSTS ABOVE 40 MPH OVERNIGHT INTO THU MORNING.
&&
.SHORT TERM /THURSDAY/...
SFC HIGH PRESSURE BUILDING SOUTH OF PA INTO THE MID ATLANTIC
REGION WILL KEEP A STRONG WESTERLY BOUNDARY LAYER FLOW OVER THE
AREA. THE COLDEST AIR MASS OF THE SEASON THUS FAR WILL COMBINE
WITH THESE WINDS TO PRODUCT SINGLE DIGIT AND TEEN WIND CHILLS
THURSDAY MORNING THROUGHOUT THE REGION.
BLYR FLOW FROM THE WSW SHOULD KEEP FOCUS OF LAKE EFFECT SNOW
NORTH OF THE BORDER...WHERE AN INTENSE SINGLE LES BAND SHOULD
AFFECT WESTERN NY STATE. FURTHER SOUTH...OROGRAPHIC EFFECTS WILL
PRODUCE A CHC OF -SHSN ACROSS THE ALLEGHENIES OF PA WITH LIGHT
ACCUMS OF LESS THAN AN INCH MOST LIKELY.
MAINLY DRY/COLD PATTERN SHOULD HOLD THROUGH THURS...AS LAKE EFFECT
REMAINS FOCUSED NORTH OF BORDER. ENS MEAN 850 TEMPS ARND -14C
SUGGEST HIGHS FROM THE 20S MTNS...TO L30S SUSQ VALLEY. A GUSTY
WEST WIND WILL CONTINUE TO MAKE IT FEEL EVEN COLDER WITH WIND
CHILLS IN THE TEENS/20S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
ACTIVE WEATHER PATTERN CONTINUES THROUGH THE PERIOD.
CORE OF COLD SHOULD MOVE OVR THE REGION THURS NITE/FRIDAY...WHEN
ENS MEAN 850 TEMPS DIP AS LOW AS -20C. WINDS SHOULD REMAIN UP...SO
DON/T SEE SUB ZERO LOWS. HOWEVER...TEMPS LIKELY TO STRUGGLE TO GET
OUT OF THE TEENS FRIDAY AFTN OVR THE HIGH TERRAIN...WHILE EVEN THE
LOWER SUSQ LIKELY TO REMAIN BLW FREEZING. BLYR FLOW STILL APPEARS
TO FAVOR SINGLE BAND JUST NORTH OF THE BORDER...ALTHOUGH IT MAY
GRAZE WARREN COUNTY FRI/FRI NITE.
SFC RIDGE SLIPS IN FROM THE SOUTH SAT/SUN...BUT LOOKS LIKE IT WILL
BREAK DOWN QUICKLY UNDER PROGRESSIVE FLOW. SHORTWAVE SLIDES NE
FROM GULF OF MEXICO STATES AND COULD POTENTIALLY BRING SOME LIGHT
SNOW TO SOUTHERN PA SAT NIGHT/SUN. ALTHOUGH LATEST NAEFS/OPER EC
SUGGEST THIS IS AN INCREASINGLY UNLIKELY EVENT.
SHORTWAVE APPROACHING FROM THE N PLAINS WILL BRING NEXT CHC OF
WIDESPREAD PRECIP ARND TUESDAY OF NEXT WEEK. CURRENT GEFS/OPER EC
TRACK SFC LOW WEST OF PA...INDICATING A BRIEF WARM UP...FOLLOWED
BY SHRASN WITH FROPA.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD MVFR CIGS WITH STRONG WESTERLY WIND GUSTS LATE THIS
AFTN AND EVENING.
WINDS WILL SHIFT TO THE WEST LATE THIS AFTERNOON. GUSTS ABOVE 35
KTS LIKELY AT MANY CENTRAL PA TERMINALS...PARTICUARLY NEAR ANY
SHRA AND LCL T THIS AFTERNOON. LAKE EFFECT WILL BE SLOW TO GET
INTO THE AREA IN THE TIME FRAME FROM LATE WED INTO THU AND FRI.
BEST CHC WILL BE LATER ON THU INTO FRIDAY ACROSS THE MTS.
OUTLOOK...
THU...MVFR/IFR NORTH AND WEST IN SNOW SHOWERS MAINLY IN THE
MOUNTAINS. STRONG WESTERLY WNDS.
FRI/FRI NIGHT...MVFR (AND LOCALIZED IFR) WEST WITH SCATTERED
SNOW SHOWERS IN MTNS OF NORTHERN AND WESTERN PA. VFR MOST OF
CENTRAL AND EAST. STILL WINDY.
SAT/SUN...MVFR TO IFR WITH MIXED PRECIPITATION POSSIBLE.
MON...MVFR TO VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 AM EST THURSDAY FOR PAZ012-018-019-
025>027-034-035-037-041-042-045-046.
WIND ADVISORY UNTIL 6 AM EST THURSDAY FOR PAZ004>006-010-011-
017-024-033.
WIND ADVISORY UNTIL 6 AM EST THURSDAY FOR PAZ028-036-049>053-
056>059-063>066.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...FITZGERALD/RXR
AVIATION...DEVOIR/GARTNER
