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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 110507 AAC
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
107 AM EDT FRI JUL 11 2014

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE WILL KEEP THE AREA DRY THROUGH MOST OF SATURDAY. THE
NEXT COLD FRONT WILL ARRIVE LATE SUNDAY AND INTO EARLY MONDAY.
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&&

.NEAR TERM /THROUGH TODAY/...
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SCATTERED CU WILL MOVE THROUGH OVERNIGHT...BUT MOST AREAS WILL
REMAIN CLEAR. EXPECT VALLEY FOG TO DEVELOP AS DAWN APPROACHES.

UPPER LEVEL HEIGHTS WILL RISE TODAY AS RIDGE BUILDS IN FROM THE
MIDWEST AND A BROAD SURFACE HIGH WILL DRIFT DOWN FROM THE GREAT
LAKES. EXPECT A MOSTLY SUNNY DAY WITH FAIR WEATHER CU DEVELOPING
AND COMFORTABLE CONDITIONS. MID JULY SUN WILL ALLOW FOR TEMPS TO
RISE INTO THE LOWER TO MID 80S. AN EASTERLY COMPONENT IN THE LOWER
LEVEL WINDS WILL ALLOW FOR SOME MOISTURE TO POOL ALONG THE EASTERN
RIDGES THIS AFTERNOON. EXPECT TO SEE A BIT MORE CLOUDS THERE AND
POSSIBLY A VERY ISOLATED SHOWER. WILL INCLUDE THE MENTION FOR A
SLIGHT CHANCE FOR A SHOWER LATER THIS AFTERNOON.
-- End Changed Discussion --

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
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SURFACE HIGH WILL DRIFT EASTWARD TONIGHT AND SATURDAY. WITH THE
AREA ON THE BACK SIDE OF THE HIGH AND RIDGING IN THE UPPER
LEVELS...OVERALL FLOW WILL BECOME SOUTHWESTERLY. THIS WILL ALLOW
FOR TEMPS TO WARM AND HUMIDITY LEVELS TO RISE.

MODELS ARE NOW SHOWING A DIFFERENT STORY FOR THE TIMING AND
STRENGTH OF A SHORTWAVE EXPECTED TO SWING THROUGH SATURDAY NIGHT.
MODELS ARE WEAKENING THE WAVE OVER THE UPPER OHIO VALLEY AND
FOCUSING ON A STRONGER WAVE OVER THE NORTHERN GREAT LAKES. THE
WEAKENING OF THE SOUTHERN WAVE IS LIKELY DUE TO A STRONGER RIDGE
THAT WILL BE IN PLACE OVER THE REGION ON SATURDAY. AS THIS WAVE
FORCES IT WAY INTO THE RIDGE IT WASTES MUCH OF ITS ENERGY. THE
STRONGER WAVE WILL BE WELL TO THE NORTH AND WILL MOVE EASTWARD IN
THE ZONAL FLOW. THIS SCENARIO WILL SLOW THE ONSET OF POPS SAT
NIGHT AND PUSH THE MORE LIKELY TIME FOR SHOWERS/STORMS INTO THE
DAYTIME HOURS ON SUNDAY.

UNTIL MODELS FIND A CONSISTENT SOLUTION FOR SAT NIGHT/SUNDAY...
FORECAST WILL BE ON THE LOW CONFIDENCE SIDE. THE TIMING AND
PLACEMENT OF THE WAVES WILL BE THE CRUCIAL ELEMENT FOR THE
FORECAST FOR THE END OF THE WEEKEND.

SUNDAY COULD BE A DAY TO KEEP AN EYE ON AS ATMOSPHERE DESTABILIZES
AND DEEP MOISTURE INCREASES. HOWEVER...MORNING CLOUD COVER WILL
BE IMPORTANT...POSSIBLY HOLDING TEMPS DOWN BELOW CONVECTIVE
LEVELS.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
SHWR AND TSTM CHCS WL CONT AS A SERIES OF UPR LVL DISTURBANCES
CROSSES THE RGN AHD OF A SLOW MOVG CDFNT. THE FNT WILL FINALLY
CROSS THE AREA TUE. SFC HIGH PRES WL THEN BLD IN THRU THU UNDER A
GT LKS UPR TROF WITH COOLER AND DRIER CONDS.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
EXPECTING A ROUND OF VALLEY FOG TONIGHT AS WINDS REMAIN LIGHT AND
SKIES CLEAR. MVFR TO IFR CONDITIONS MOST LOCATIONS ALTHOUGH SPOTS
LIKE MGW...FKL...AND DUJ COULD REACH LIFR. FOG SHOULD LIFT BY
13-14Z WITH SCT VFR CU ONCE AGAIN DEVELOPING.

.OUTLOOK.../FRIDAY THROUGH TUESDAY/...
RESTRICTIONS IN SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
SUNDAY/MONDAY.

&&

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

&&

$$