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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 150726
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
326 AM EDT SAT JUN 15 2013

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE ALONG THE EAST COAST WILL ALLOW FOR DRY
CONDITIONS...WHILE A COLD FRONT WILL BRING A RETURN TO SHOWERS AND
THUNDERSTORMS FOR SUNDAY.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH SUNDAY/...
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HIGH PRESSURE IS CURRENTLY ACROSS MUCH OF THE EASTERN UNITED
STATES...AND THE HIGH WILL DRIFT OFFSHORE DURING THE DAY. WHILE THE
DAY WILL START MOSTLY CLEAR...THERE SHOULD BE SOME INCREASE IN
CLOUDS DURING THE AFTERNOON HOURS AHEAD OF SYSTEM DEVELOPING OVER
THE PLAINS. DEVELOPMENT OF WEST-SOUTHWESTERLY WINDS SHOULD ALLOW
HIGHS TO CLIMB A COUPLE OF DEGREES FROM YESTERDAY.

AS LOW PRESSURE MOVES ACROSS THE GREAT LAKES...COLD FRONT SHOULD
SWEEP ACROSS THE REGION ON SUNDAY. HOWEVER...WITH PRECIPITATION
GENERALLY IN ADVANCE OF THE FRONT...RAIN IS EXPECTED TO BEGIN LATE
TONIGHT AND EXTEND INTO SUNDAY. WHILE LAPSE RATES ARE NOT TERRIBLY
IMPRESSIVE...COULD SEE CAPE VALUES AROUND 1000 J/KG AND GENERALLY
UNIDIRECTIONAL WIND SHEAR ALLOWING FOR AN ISOLATED STRONG/SEVERE
STORM. AT THIS POINT...DO NOT SEE MUCH THAT SUGGESTS THIS WOULD BE
A WIDESPREAD EVENT.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
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AS FRONT DROPS SOUTH OF THE REGION SUNDAY NIGHT...HAVE ACCORDINGLY
DROPPED POPS...ALTHOUGH THERE IS STILL A HIGH CHANCE FOR SHOWERS AND
THUNDERSTORMS SUNDAY EVENING SOUTH OF THE MASON-DIXON LINE. MONDAY
REMAINS A BIT OF A MUDDLED PICTURE. A POORLY DEFINED FRONT SHOULD BE
NORTH OF THE REGION...WHILE SUNDAY/S FRONT SHOULD REMAIN SOUTH OF
THE REGION. THE 00Z NAM/GFS BOTH SUGGEST CONDITIONS MAY BE
COMPLETELY DRY. FOR NOW...HAVE NOT CHANGED THE FORECAST DURING THIS
PERIOD. BY MONDAY NIGHT HAVE THROWN OUT THE GFS SOLUTION WITH
CONVECTIVE FEEDBACK BRINGING A WINTER-LOOKING STORM BARRELING
THROUGH THE REGION. HAVE STUCK CLOSER TO THE ECMWF SOLUTION...WHICH
GENERALLY KEEPS ALL POPS SOUTH AND EAST OF PITTSBURGH AS FRONT
FINALLY SHIFTS EAST. TEMPERATURES SHOULD REMAIN CLOSE TO CLIMATOLOGY
THROUGH THE PERIOD.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
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MDLS DIFFER IN DEPICTIONS OF SITUATION FOLLOWING PASSAGE OF THE
EARLY WEEK FRONT...SO FORECAST WAS BASED ON NAEFS MEANS WHICH
FEATURED A LOW AMPLITUDE ERN CONUS TROF GRADUALLY FILLING NEXT
WEEKEND. TEMPS WERE THUS FORECAST A FEW DEGREES UNDR THE SEASONAL
AVERAGES UNTIL THAT TIME FRAME. MINIMAL CONFIDENCE POPS WERE
PROGGED AOB CLIMO.
-- End Changed Discussion --

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
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WITH A CLEAR SKY AND CALM WIND...EXPECT THAT SOME MVFR FOG WILL
DEVELOP THIS MRNG...ESPECIALLY IN RIVER VALLEYS. GIVEN THE NEGATIVE
VERTICAL HUMIDITY CHANGES...GENL MVFR/ISOLD IFR SHOULD SUFFICE UNTIL
THE SHALLOW FOG QUICKLY MIXES OUT AFTR SUNRISE.

WITH LOW INVERSION LEVELS AND HIGH TEMP/DP SPREADS...EXPECT ONLY
HIGH BASED FLAT CU THIS AFTN IN THE CLOUD DEPARTMENT.

.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
PERIODIC RAIN AND RESTRICTIONS ARE ANTICIPATED SUNDAY THROUGH
EARLY TUESDAY.
-- End Changed Discussion --

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$