-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 172212
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
612 PM EDT FRI MAY 17 2013

.SYNOPSIS...
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SEASONABLY WARM WEATHER CAN BE EXPECTED THIS WEEKEND...BUT A RAIN
CHANCE REMAINS IN THE FORECAST AS A FRONT MEANDERS OVER THE REGION.
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&&

.NEAR TERM /THROUGH SATURDAY/...
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ONLY MINIMAL ADJUSTMENTS WERE NEEDED FOR THE EARLY EVE UPDATE AS
SHWRS AND TSTMS WERE CONFINED TO AREAS SOUTH OF A PARKERSBURG TO
CLARKSBURG WV LINE...SOUTH OF FRONTAL BOUNDARY BEST INDICATED VIA
SFC DEWPOINTS AND CONVERGENT WIND.

HAVE THUS MAINTAINED A DRY FORECAST FOR TNGT...WITH EXCEPTION FOR
THE RIDGES OF TUCKER COUNTY WHERE UPSLOPE ENHANCEMENT MAY SPPRT
SOME LGT SHWRS.

OTHERWISE...MODELS CONTINUE TO SUGGEST...WITH SOME TIMING DIFFERENCES...THAT
THE FRONT WILL ONCE AGAIN FLUCTUATE ACROSS THE REGION SATURDAY. THE
BIGGEST QUESTION WILL BE THE NORTHERN EXTENT OF LIFT FROM AN
APPROACHING SHORTWAVE THAT IS PROGGED TO REACH THE REGION IN THE
AFTERNOON. EACH OF THE DETERMINISTIC MODELS HANDLES THIS
DIFFERENTLY...THUS NOTHING MORE THAN CHANCE POPS WERE ADDED
SATURDAY AFTERNOON. WITH MORE CLOUD COVER EXPECTED
SATURDAY...TEMPERATURES WERE KEPT A FEW DEGREES COOLER THAN TODAY.
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&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
THE BOUNDARY SHOULD MAKE IT`S FINAL PUSH NORTHWARD BY SATURDAY
NIGHT/SUNDAY LEADING TO BETTER MOISTURE AND INSTABILITY THROUGH
THE REMAINDER OF THE SHORT TERM. HOWEVER SHORTWAVE TIMING AND
PLACEMENT CONTINUES TO DIFFER OWING TO LOWER CONFIDENCE IN THUNDERSTORM
COVERAGE. SO CHANCE POPS WERE CONTINUED...MAINLY IN THE AFTERNOONS
BOTH SUNDAY AND MONDAY.

STRENGTHENING SOUTHERLY FLOW SHOULD ALLOW TEMPERATURES TO WARM
EACH DAY...EVEN IF THERE IS CLOUD COVER SO HIGHS IN THE LOWER 80`S
WERE INTRODUCED BY MONDAY AFTERNOON.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
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UPPER LEVEL RIDGING WILL CONTINUE TO AMPLIFY OVER THE EASTERN
HALF OF THE CONUS AS A CUTOFF LOW DEVELOPS OVER THE NORTHERN
PLAINS. THIS LOW WILL SLOWLY MAKE IT`S APPROACH THROUGH THE
PERIOD...HELPING TO SWING AN ASSOCIATED FRONT ACROSS THE REGION BY
LATE WEDNESDAY/EARLY THURSDAY. HOWEVER...DIFFERENCES STILL REMAIN
IN THE AMOUNT OF CONVECTIVE ACTIVITY THERE WILL BE IN THE WARM
SECTOR TUESDAY AND WEDNESDAY AS DIFFERENT SHORTWAVES MOVING
THROUGH THE UPPER LEVEL FLOW ARE TIMED DIFFERENTLY FROM RUN TO
RUN.

GIVEN THESE DIFFERENCES...OPTED TO REMAIN CONSERVATIVE WITH POPS
UNTIL LATE TUESDAY BEFORE INCREASING CHANCES IMMEDIATELY AHEAD OF
THE COLD FRONT. TEMPERATURES WERE KEPT NEAR MOS/HPC GUIDANCE BUT
AMPLE MOISTURE AND CLOUD COVER COULD PRECLUDE READINGS FROM REACHING
THE MID 80`S AS SUGGESTED.
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&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
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GOOD RADIATIONAL COOLING OVERNIGHT WILL SPPRT SOME PATCHY MVFR FOG
FOR THE EARLY MORNING HOURS. OTHERWISE...SCATTERED TO BROKEN CU
ARE EXPECTED TO FORM AGAIN ON SATURDAY AS HEATING/MIXING IMPROVE.
SOME BRIEF RESTRICTIONS ARE POSSIBLE IN THE SHOWERS OR ISOLATED
THUNDERSTORMS...WITH THE BTR CHC AT SRN TERMINALS.

.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
THERE WILL BE AN INCREASING CHC FOR RESTRICTIONS IN DIURNALLY SPPRTED
SCT SHOWERS AND THUNDERSTORMS DURING THE FIRST HALF OF THE WEEK.
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&&

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

&&

$$

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