-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 160536
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
136 AM EDT SUN JUN 16 2013

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

&&

.NEAR TERM /THROUGH TODAY/...
-- Changed Discussion --
WITH 130AM UPDATE HAVE SLOWED DOWN ARRIVAL OF PRECIPITATION
SLIGHTLY...CONSIDERING PRECIPITATION HAS ALSO SLOWED DOWN IN ITS
EASTWARD TREK. ALSO NUDGED HOURLY TEMPERATURE TRENDS. PREVIOUS
DISCUSSION FOLLOWS.

A WEAKENING MCV WILL APPROACH AND SHOULD REACH THE FORECAST AREA
LATE TONIGHT. CONTINUED WITH THE INHERITED POP TIMING AS BOTH THE
HI RES AND DETERMINISTIC MODELS LINE UP FAIRLY WELL. OTHERWISE
POPS WILL INCREASE THROUGH SUNDAY MORNING AS MOISTURE OUT AHEAD OF
A WEAK COLD FRONT APPROACHES AND CROSSES THE REGION THROUGH
SUNDAY. MODEL SOUNDINGS CONTINUE TO FORECAST AROUND 1000J/KG OF
CAPE AND DECENT 0-6KM WIND SHEAR SO COULD NOT RULE OUT A FEW
THUNDERSTORMS REACHING NEAR SEVERE THRESHOLDS. OF COURSE...THIS
WILL BE HEAVILY BASED ON HOW MUCH CLOUD COVER THERE IS TO PROHIBIT
SURFACE HEATING.

TEMPERATURES WERE KEPT SLIGHTLY NEAR MEX VALUES.
-- End Changed Discussion --

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
FRONTAL BNDRY FROM SUN WILL STALL IN THE RGN ON MON AND TUE. THERE
IS CONSIDERABLE UNCERTAINTY IN PCPN POTL ON MON. WITH GOOD
INSOLATION MON MRNG...INSTBY WILL BE PLENTIFUL. LIFT WILL BE THE
MORE QUESTIONABLE COMPONENT OF THE MIX. FCST WILL CONT POPS WITH
BEST FOCUS ALONG THE STALLED FRONTAL BNDRY...WHICH SHOULD FOCUS
ANY CNVCTV DVLPMT. IF THERE ARE TSTMS...THERE IS THE POTL FOR A
FEW SVR TSTMS. BUT THE PROB IS CONDITIONAL UPON THEIR DVLPMT.

DESPITE COOLER BNDRY LYR OWING TO CLD CVR...TSTMS AGAIN WILL BE
PSBL ON TUE AS PREVLY-STALLED BNDRY BCMS MORE SHARPLY DEFINED IN
CNTRL AND SRN ZONES WITH AN APRCHG SHRTWV TROF. GUIDANCE SUGGESTS
A TSTM CLUSTER WILL HELP DRIVE CDFNT SEWD BY TUE AFTN AND SE OF
FCST AREA TUE NGT.  UPDATE...KRAMAR

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
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.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
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AN APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT WILL BRING
SHOWERS AND INCREASING CHANCES FOR THUNDERSTORMS TODAY. FOR
NOW...GIVEN A LACK OF CONFIDENCE IN INSTABILITY PROGS...WILL KEEP
MENTION OF THUNDER OUT OF ANY SPECIFIC TAF SITE. A GRADUAL
DETERIORATION TO MVFR CAN BE EXPECTED...WITH IFR IN HEAVIER SHWRS
AS PER SHREF PROBABILITIES AND LAMP GUIDANCE.

.OUTLOOK...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPROACHES AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN
VFR CONDITIONS FOR WEDNESDAY AND THURSDAY.
-- End Changed Discussion --

&&

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

&&

$$