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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 160204
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1004 PM EDT SAT JUN 15 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 SUNDAY/...
-- Changed Discussion --
VERY LIGHT PRECIP ASSOCIATED WITH A WEAK SHORTWAVE WILL CONTINUE
TO SHIFT EASTWARD THIS EVENING. DID NOT CONTINUE SLIGHT CHANCE
POPS ACROSS AREA WITH THIS FEATURE AS NOT MUCH OF THE PRECIP IS
MAKING IT TO THE GROUND WITH SO MUCH DRY AIR AT LOWER LEVELS.

BEHIND THIS WAVE 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 /SUNDAY NIGHT 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 /02Z SUNDAY THROUGH THURSDAY/...
HIGH CIRRUS AND MAYBE A STRAY SHOWER WILL APPROACH THE REGION THIS
EVE BUT SHOULD KEEP VFR AT ALL PORTS FOR MUCH OF THE NIGHT.
APPROACHING SHORTWAVE AND COLD FRONT WILL BRING RAIN AND INCREASING
CHANCES FOR THUNDERSTORMS THROUGH MUCH OF SUNDAY. FOR NOW...WILL
KEEP MENTION OF THUNDER OUT OF ANY SPECIFIC TAF SITE SINCE
CONFIDENCE IN IMPACTS REMAINS LOW. BUT...DID BEGIN TO TREND
DOWNWARD WITH CIGS AND VSBYS IN HEAVIER RAIN THROUGH THE AFTERNOON
SUNDAY PER SHREF PROBABILITIES AND LAMP GUIDANCE.

.OUTLOOK...
SUB-VFR CIGS MAY LINGER INTO TUESDAY. THUNDERSTORMS WILL BE
POSSIBLE AGAIN TUESDAY AFTERNOON WITH THE PASSAGE OF A SHORTWAVE.
VFR TO RETURN UNDER HIGH PRESSURE WEDNESDAY AND THURSDAY.

&&

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

&&

$$