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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 161900
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
300 PM EDT THU MAY 16 2013

.SYNOPSIS...
-- Changed Discussion --
AN WEST-EAST FRONTAL BOUNDARY WILL REMAIN ALONG THE MASON DIXON
LINE INTO FRIDAY MORNING. MEANWHILE...HIGH PRESSURE WILL MIGRATE
EASTWARD ACROSS SOUTHEASTERN CANADA WITH ONSHORE FLOW DEVELOPING
ACROSS THE MID- ATLANTIC REGION. THE FRONTAL BOUNDARY WILL SLOWLY
PUSH BACK TO THE NORTH AS A WARM FRONT OVER THE WEEKEND...AND LIFT
NORTH OF THE AREA BY EARLY NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
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HIGH PRES RIDGE AND ASSOC DRY AIR MASS NOSES SEWRD INTO PA
TONIGHT...BRINGING MCLEAR SKIES AND LIGHT WINDS TO ALL OF CENTRAL
PA. THE DRIEST AIR...AS DEPICTED BY GEFS NEGATIVE PWAT
ANOMALIES...REMAIN ACROSS THE NORTHERN HALF OF THE STATE...WHERE
READINGS ARE LIKELY TO DIP INTO THE M/U30S. CAN/T RULE OUT SOME
PATCHY FROST UP THERE...BUT GROWING SEASON HAS NOT OFFICIALLY
BEGUN UP THERE...SO NO ADVISORY NEEDED.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
SFC HIGH PRES WILL SLIDE EWD FROM ONTARIO TO THE MARITIMES BY 12Z
SUNDAY...WITH ONSHORE FLOW DEVELOPING ACRS THE MID-ATLC STATES.
EXPECT SFC RIDGING AND LACK OF ANY SIGNIFICANT MID-UPPER LEVEL
FORCING TO LIMIT PCPN THROUGH MOST OF THE PERIOD. THE HIGHEST POPS
ARE OVER THE SERN ZONES SAT NGT AS AN UPPER LEVEL WAVE DRIFTS EWD
ACRS KY/TN INTO THE CNTRL APPLCHNS AND INTERACTS WITH ONSHORE MSTR
FEED INTERSECTING RETREATING Q-STNRY/WARM FRONT LIFTING NWD OVER
THE MID-ATLC. EXPECT LOW CLOUDS TO DEVELOP FROM SOUTH TO NORTH ON
SAT NGT IN SERLY FLOW REGIME. TEMPS WILL BE WARMER ON FRIDAY WITH
MORE SUN.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE CONTINUES TO TREND COOLER FOR SUNDAY WITH HIGHS IN THE
MID-UPPER 60S...AS MOIST ONSHORE FLOW STRENGTHENS /-2SD 850MB U
WIND ANOMALY IN GEFS/ AND BRINGS EXTENSIVE CLOUD COVER TO THE
REGION. MDL LI PROGS SHOW A CAD PATTERN IN THE LOW-LEVELS AS THE
WARM FRONT PIVOTS AND STALLS ALONG THE ALLEGHENY FRONT. WITH
STABLE CONDITIONS EXPECTED...CHANGED WX TYPE TO LGT RAIN AS
INSTABILITY SHOULD BE LOCATED WEST OF THE MTNS. FOCUS FOR PCPN
INTO MONDAY SHOULD REMAIN SOUTH OF PA OVER THE VA/NC IN CONJCT
WITH UPPER LEVEL WAVE AND MAX PWAT ANOM NR +2SD. HIGHEST POPS ARE
AGAIN OVER THE ERN 1/2 OF THE CWA AS SELY FLOW CONTS TO IMPINGE ON
SLOWLY RETREATING/DIFFUSE N-S WARM FRONT.

THE LG SCALE PATTERN IS FCST TO TURN DECIDEDLY MORE AMPLIFIED NEXT
WEEK...WITH THE MAIN SYNOPTIC FEATURE OF INTEREST BEING AN UPPER
LOW OVER THE NRN PLAINS/UPR MS VLY. H5 HGTS SHOULD RISE DOWNSTREAM
OF THIS SYSTEM...WITH CENTRAL PA LKLY BREAKING INTO THE WARM
SECTOR BY NEXT TUES AS THE PESKY WARM FRONT LIFTS NORTH INTO NEW
ENGLAND. THIS SHOULD AFFORD ONE OR TWO VERY WARM LATE SPRING DAYS
WITH HIGHS 75-80F. THERE IS A HIGH SPREAD BETWEEN THE GFS/ECMWF
CONCERNING THE POTENTIAL UPPER MIDWEST CUT-OFF. THEREFORE UTILIZED
A 50/50 BLEND OF THEIR RESPECTIVE MOS PRODUCTS FOR THE DAY 5-7
FCST.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
WIDESPREAD VFR CONDS EXPECTED THROUGH THE TAF PD AS WEAK HIGH
PRESS SPREADS ACROSS THE STATE. SOME REDUCED VSBYS IN FOG/HZ
POSSIBLE AROUND SUNRISE FRIDAY ACROSS THE LOWER SUSQ VALLEY...BUT
CONFIDENCE NOT HIGH ENOUGH TO INCLUDE IN TAFS ATTM.

.OUTLOOK...

FRI-SUN...NO SIG WX EXPECTED.
MON...AM LOW CIGS POSSIBLE.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...GARTNER/STEINBUGL
NEAR TERM...GARTNER
SHORT TERM...GARTNER/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...GARTNER