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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 251154
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
754 AM EDT SAT MAY 25 2013

.SYNOPSIS...
A DEEP...SLOW MOVING UPPER LOW OVER SOUTHERN NEW JERSEY THIS MORNING
AND ASSOCIATED COLD AIR ALOFT WILL CONTINUE TO BRING UNSEASONABLY
CHILLY AND QUITE BREEZY CONDITIONS TODAY. CANADIAN HIGH PRESSURE
CENTERED OVER THE UPPER GREAT LAKES WILL BUILD SOUTHEAST OVER
PENNSYLVANIA LATER SUNDAY INTO MEMORIAL DAY ENSURING FAIR WEATHER.
TEMPERATURES WILL BEGIN THE WEEKEND WELL BELOW NORMAL BUT MODERATE
BY MEMORIAL DAY.

&&

.NEAR TERM /UNTIL 11 AM THIS MORNING/...
EARLY MORNING IR SAT LOOP SHOWS AREAS OF BKN-OVC...COLD AIR STRATO
CU STREAMING SWD ACROSS THE WRN MTNS OF PENN AND ALSO THE FAR ERN
PART OF THE CWA. ELSEWHERE SKIES WERE MAINLY CLEAR WITH A 5-10KT
WEST TO NW BREEZE...WHICH WAS GUSTING AT TIMES INTO THE MID TEENS.

TEMPS ACROSS THE CENTRAL MTNS AND SUSQ REGION WERE MAINLY BETWEEN
40 AND 45. THE ALLEGHENIES WERE SEEING DAYBREAK TEMPS IN THE LOWER
TO MID 30S.

NW WINDS WILL PICK UP QUICKLY INTO THE 10 TO 20 MPH RANGE WITH GUSTS
AROUND 25 MPH BY 8 AM THIS MORNING. GUSTS WILL TOP 30 MPH IN SOME
AREAS BY 15Z.

&&

.SHORT TERM /11 AM THIS MORNING THROUGH 6 PM SUNDAY/...
LARGE SCALE SUBSIDENCE AND ANOMALOUSLY DRY AIR /WITH LAYER PRECIP
WATER VALUES ONLY AROUND 0.25 OF AN INCH/ WILL RESIDE OVER ALL OF
CENTRAL PA TODAY...IN THE WAKE OF THE SLOWLY DEPARTING UPPER
LOW.

EXPECT MOSTLY SUNNY SKIES TO CONTINUE ACROSS MUCH OF THE
REGION...WITH A FEW PERIODS OF BKN STRATO CU AS A WEAK/COMPACT
SHORT WAVE /AND ASSOCIATED POCKET OF COOLER AIR ALOFT/ DROPS SE
ACROSS THE COMMONWEALTH THIS AFTERNOON.

TEMPS MAY STILL BE COLD ENOUGH ALOFT TO SUPPORT A MORE EVEN MIX OF
SUN AND CUMULUS ACROSS ACROSS THE EASTERN COUNTIES...ESP SULLIVAN.
HOWEVER...WILL CONTINUE TO KEEP THE MENTION OF EVEN ISOLATED SHRA
OUT OF THE FCST BASED ON AFOREMENTIONED LOW PWATS AND LACK OF ANY
SIGNIFICANT FORCING MECHANISM.

MDL SOUNDINGS SHOW DEEP MIXING TO 8H...WHICH SHOULD TRANSLATE TO
HIGHS FROM THE M50S ACROSS THE HIGHER TERRAIN...TO THE MID 60S
THROUGHOUT MUCH OF THE SUSQ RIVER VALLEY. THESE READINGS ARE 10-15F
WARMER THAN FRIDAY...BUT STILL AROUND 10 DEG F BELOW NORMAL.
AS THE BLYR DEPTH INCREASES QUICKLY THIS MORNING...EXPECT NW
WINDS TO BECOME GUSTY AGAIN BY LATE THIS MORNING. BUFKIT SOUNDINGS
SUPPORT GUSTS AT LEAST IN THE 25-30KT RANGE BY AFTN.

THE MAINLY CLEAR SKIES...AND VERY DRY AIR WILL LEAD TO CHILLY TEMPS
TONIGHT...AND A FREEZE WATCH WAS ISSUED FOR PRACTICALLY THE SAME
AREA UNDER THE CURRENT FREEZE WARNING. HOWEVER...THE LIGHT TO
MODERATE WEST TO NW BREEZE SHOULD KEEP FROST FORM FORMING WHERE
TEMPS DIP TO NEAR OR SLIGHTLY BELOW FREEZING IN THE NORTH AND WEST.
MIN TEMPS IN THE UPPER 30S TO LOWER 40S WILL PREVENT ANYTHING MORE
THAN PATCHY LIGHT FROST IN THE SHELTERED...NORMALLY COLDER  RURAL
VALLEYS WHERE WINDS COULD DIMINISH TO UNDER 5 KTS FOR A FEW HOURS
EARLY SUNDAY.

THE WEATHER ON SUNDAY WILL IMPROVE FURTHER WITH ABUNDANT
SUNSHINE...SLIGHTLY MILDER TEMPS...AND LESS GUSTINESS TO THE WIND.
HIGHS SUNDAY WILL VARY FROM THE LOWER 60S ACROSS THE MTNS...TO THE
UPPER 60S IN THE SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
DRY WEATHER WITH TEMPS REBOUNDING TO RIGHT AROUND NORMAL MONDAY WILL
BEGIN THE EXTENDED PERIOD...AS WE BENEFIT FROM A SFC AND UPPER RIDGE
BUILDING IN FROM THE WEST.

THIS EXCELLENT WEATHER TO ACCOMPANY OUR MEMORIAL DAY REFLECTIONS AND
ACTIVITIES WILL BE RATHER SHORT-LIVED. THE FORECAST FROM TUESDAY
THROUGH AT LEAST MIDWEEK GETS MURKY AS THE BUILDING SUB TROPICAL
RIDGE OVER THE SOUTHERN STATES SHOVES THE WESTERLIES NORTHWARD. WITH
US BEING ON THE SOUTHERN EDGE OF THESE WESTERLIES/NORTHERN EDGE OF
THE SUBTROPICAL RIDGE...WE WILL BECOME VULNERABLE TO UPSTREAM MCS
DEVELOPMENT AS THE HEAT AND HUMIDITY BEGINS TO MAKE INROADS TO THE
REGION ONCE AGAIN.

DIFFERENCES IN THE MODEL TIMING OF THESE CONVECTIVE COMPLEXES IS
BIG WITH THE OPERATIONAL GFS SHOWING A WET DAY TUESDAY...AND THE
ECMWF SUGGESTING THE CONVECTION STAYS MAINLY SOUTH OF HERE AT THAT
TIME. GEFS SPLASHES A FAIR AMOUNT OF DIURNALLY FAVORED PRECIP
AROUND JUST ABOUT EVERY DAY STARTING TUESDAY. THE MEAN UPPER FLOW
AND ACCOMPANYING SURFACE PATTERN SUGGEST WHATEVER SEMBLANCE OF A
WARM FRONT THERE IS PASSES THROUGH ON WEDNESDAY...WITH THE
REMAINDER OF THE WEEK FIRMLY UNDER THE INFLUENCE OF THE BERMUDA
HIGH AND WARM MUGGY SOUTHWEST FLOW. WITH THE OPERATIONAL
GFS/ECMWF BOTH PREDICTING A SURGE IN MID LEVEL TEMPS BY LATER WED
INTO THURSDAY...I AM THINKING WE WILL SPEND MUCH OF THE TIME AFTER
MID WEEK PRETTY CAPPED LEADING TO HAZY HOT AND HUMID CONDITIONS
WITH FAIRLY SMALL CHANCES FOR SHOWERS AND THUNDERSTORMS. I LIKE
OUR CURRENT FORECAST WHICH DOWNPLAYS THE CHANCES FOR RAIN AFTER
WEDNESDAY...AND WILL CONTINUE ALONG THOSE LINES THROUGH FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
ALTHOUGH VFR AND MAINLY CLEAR CONDITIONS EXIST OVER MOST OF CENTRAL
PA...PERSISTENT MVFR/IFR CIGS REMAIN LOCKED IN OVER THE WESTERN
AND NORTHERN MOUNTAINS. EXPECTING THESE LOWER CLOUDS TO DISSIPATE
OVER THE NEXT 2 TO 3 HOURS...AND VFR CONDITIONS WILL PREVAIL
ACROSS THE ENTIRE REGION FOR THE BALANCE OF THE DAY. WINDS WILL
AGAIN BE STRONG TODAY...AND EXPECT SURFACE WINDS TO FREQUENTLY BE
GUSTING BETWEEN 20 AND 30 KTS.

VFR CONDITIONS WILL PREVAIL OVERNIGHT...AND MONDAY...WITH UPPER
LOW PULLING EAST...AND SURFACE HIGH BUILDING INTO THE REGION.

WARM ADVECTION ON TUESDAY COULD SET OFF A FEW SHOWERS OR STORMS...
MAINLY LATE. WARMER WED...BUT STILL A CHC OF A SHOWER OR STORM.

.OUTLOOK...
SUN-MON...VFR.
TUE-WED...MAINLY VFR...BUT SCT TSTM IMPACTS POSSIBLE.
-- End Changed Discussion --

&&

.FIRE WEATHER...
ALL CRITERIA FOR RED FLAG CONDITIONS WILL BE MET TODAY...AS A
GUSTY NORTHWEST WIND /BETWEEN 30 AND 35 MPH AT TIMES/ DEVELOPS
BETWEEN DEEPENING LOW PRESSURE NEAR THE NEW ENGLAND COAST AND
HIGH PRESSURE OVER THE UPPER GLAKES/ HELPS TO FURTHER DRY OUT FINE
FUEL MOISTURE BELOW ITS PRESENT 10-12 PERCENT LEVEL ACROSS THE
REGION.

RELATIVE HUMIDITY THIS AFTERNOON WILL DROP TO A MINIMUM OF 25 TO
30 PERCENT.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
FREEZE WATCH FROM LATE TONIGHT THROUGH SUNDAY MORNING FOR
PAZ004>006-010>012-017-018-024-033-037-041-042.
RED FLAG WARNING FROM NOON TODAY TO 7 PM EDT THIS EVENING FOR
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066.
-- End Changed Discussion --

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...JUNG
FIRE WEATHER...