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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 132321
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
721 PM EDT THU JUN 13 2013

.SYNOPSIS...
BEHIND LOW PRESSURE HEADING TOWARD THE EAST COAST...IT WILL BE
MUCH COOLER AND LESS HUMID TONIGHT INTO FRIDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
CANCELLED THE REMAINING FLOOD WATCH AS HEAVY RAIN HAS MOVED OUT OF
THE REGION AND NO LONGER POSES A FLOOD THREAT. ADJUSTED POPS FOR
NARROW BAND OF SHOWERS MOVING SOUTH ASSOCIATED WITH BACK END OF
LOW PRESSURE/ UPPER TROUGH AXIS. THESE SHOWERS SHOULD END BY EARLY
EVENING. PRESSURE GRADIENT BEHIND EXITING SURFACE LOW OVER EASTERN
PA WILL KEEP GUSTY WEST TO NORTHWEST WINDS THIS EVENING AND MUCH
COOLER TEMPERATURES.

FOR FRIDAY A SHORTWAVE ON THE BACKSIDE OF UPPER LEVEL SYSTEM WILL
BRING ENOUGH INSTABILITY FOR A LOW CHANCE OF SHOWERS IN THE
AFTERNOON...ESPECIALLY ALONG THE RIDGES. TEMPERATURES WILL BE
ABOUT 5 TO 8 DEGREES BELOW AVERAGE TONIGHT AND FRIDAY.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
SURFACE HIGH PRESSURE WILL KEEP THE REGION DRY FRIDAY NIGHT
THROUGH SATURDAY WITH TEMPERATURES RETURNING TO NEAR AVERAGE
SATURDAY AFTER A COOL START.

NEXT SHORTWAVE WILL BE RACING EAST LATER SATURDAY NIGHT WITH WARM
ADVECTION INCREASING CLOUDS AND SHOWER CHANCES BY DAYBREAK
SUNDAY. UPPER POPS TO LIKELY FOR SUNDAY AS MODELS IN GOOD
AGREEMENT ON DEEP MOISTURE AND LIFT AS WEAK FRONT CROSSES THE
REGION AND LOOKS TO STALL NEAR  OF THE MASON DIXON LINE LATE DAY
SUNDAY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A STNRY FNT NR THE UPR OH VLLY SUN NGT INTO MON NGT WL CONT
SHWR/TSTM CHCS. AN UPR LVL TROF AND CDFNT ARE EXP TO CROSS THE GT
LKS TUE WITH BETTER CHCS FOR SHWRS/TSTMS. HIGH PRES BLDS IN WITH
DRY WEA WED AND THU. OVERALL TEMPS SHOULD BE NR OR SLIGHTLY BLO
SEASONAL AVGS.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
LOWER CLOUDS ASSOCIATED WITH NE STORM SYSTEM TRYING TO LIFT ENE.
HOWEVER, BROADER CYCLONIC FLOW AS SYSTEM PULLS NE WILL BRING
CONTINUED LOWER LEVEL STRATCU MOISTURE PLUME FROM NORTH AND WITH
LAKE TRAJECTORY. HRRR SUGGESTING SOME CLEARING OVERNIGHT BUT EVEN
IT DEVELOPS LOWER CEILINGS OFF THE LAKE BY MORNING. WRF GOES-R
SUGGESTS SOME SCATTERING OUT EARLY BUT THEN BRINGS STRATO- CU BACK
IN OVERNIGHT. WILL CONTINUE WITH SC DECK OVERNIGHT GENERALLY
BROKEN. WILL GO SKC AT ZZV. SOME GRADIENT APPEARS TO KEEP UP
OVERNIGHT BUT GUSTS SHOULD DIMINISH. AS SUGGESTED BY HRRR WILL
BRING SOME LOWER STRATUS IN AROUND 09Z BUT WITH SOME GRADIENT
WILL NOT GO VERY LOW ON ANY BR. NORTHWEST FLOW TO CONTINUE ON
FRIDAY. COULD BE A SPRINKLE OR TWO AROUND AND WENT GENERALLY WITH
BKN SC DECK IN PA AND SCATTERED IN OH.

.OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
FINALLY CYCLONIC FLOW DIMINISHED FRIDAY NIGHT AS HIGH PRESSURE
BUILDS INTO REGION. EXPECT VFR THROUGH SUNDAY MORNING. THEN NEXT
SYSTEM MOVES INTO AREA FOR THE REMAINDER OF SUNDAY INTO EARLY
MONDAY...BRIEF HIGH PRESSURE THROUGH MIDDAY MONDAY AND THEN ANOTHER
STORM SYSTEM AND ASSOCIATED FRONT THROUGH TUESDAY WITH SOME
RESTRICTIONS POSSIBLE.
-- End Changed Discussion --

&&

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

&&

$$