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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 181449 AAA
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
1049 AM EDT SAT MAY 18 2013

.SYNOPSIS...
-- Changed Discussion --
SEASONABLY WARM DAYS WILL CONTINUE THROUGH THE WEEKEND...WITH
TEMPERATURES REMAINING COOLER THAN NORMAL IN THE MOUNTAINS.
SHOWERS AND POSSIBLY THUNDERSTORMS WILL BE POSSIBLE MOST DAYS
THROUGH THE WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
SHWRS ASSOCIATED WITH SLOW-MOVG UPR LOW WILL MOVE NEWD INTO WRN
ZONES THRU RMNDR OF THE MRNG AND WILL CONT INTO THE AFTN. CVRG OF
SHWRS WILL INCR ACRS SRN ZONES IN VCTY OF STALLED FRONTAL BNDRY.
RELATIVELY DRIER AND COOLER AIR FROM THE NE WILL RMN ENSCONCED
OWING TO WEAK MID-LVL FLOW. GRADIENT IN MAXIMA XPCD...ALTHOUGH
MRNG CLRG HAS AIDED IN FOCUSED HEATING ACRS CNTRL ZONES. 12Z KPIT
RAOB SUGGESTS MAXIMA IN UPR 70S TDA...APRCHG 80 IN ERN OH.

ONLY MODEST INSTBY RESULTING FROM WEAK MID-LVL LAPSE RATES WILL
PROMOTE CHC OF TSTMS THIS AFTN AMID GREATER CVRG OF SHWRS. POPS
WERE INCRD CONSIDERABLY TDA AND TNGT TO REFLECT ONGOING AND XPCD
SHWRS AND GUIDANCE TRENDS.

INCRG BNDRY LYR MSTR OVNGT WILL AID IN GENERATION OF STRATUS. CLDY
SKIES XPCD OVNGT...WHICH WILL AID IN RETARDING RADIATIONAL
COOLING. MINIMA IN MID 50S-LWR 60S XPCD AS A RESULT. PCPN WILL BCM
FOCUSED IN HIGHER TERRAIN LATE TNGT AS UPR WAVE MOVES SLOWLY EWD.
POPS WERE ADJUSTED ACCORDINGLY.     UPDATE...KRAMAR
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
WEAK FRONT CONTINUES TO MEANDER JUST SOUTH OF REGION.
MEANWHILE...APPALACHIAN PLATEAU CONTINUES COOL WITH SHOWERS UNDER
E-SE FLOW. REMNANT MOISTURE WILL CONTINUE TO GIVE CHANCE POPS WITH
A DIURNAL MINIMUM OVERNIGHT AND INCREASE WITH AFTERNOON HEATING
AND SUBSEQUENT INSTABILITY INCREASE. FRONTAL SYSTEM FINALLY TO
PUSH NORTHWARD LATER MONDAY WITH INCREASE IN SOUTHERLY FLOW AND
RISE IN TEMPERATURES.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL RIDGING CONTINUES IN PART DUE TO MIDWEST CUTOFF LOW
PUSHING EAST. MEANWHILE...SURFACE FRONT STILL DRAPED CLOSE TO OR
JUST NORTH OF REGION. MID-WEST UPPER LEVEL LOW WILL CONTINUE TO
PUSH EAST BUT LOSE INTENSITY AND IN FACT OPENS UP AS IT
APPROACHES OUR AREA. AS A RESULT...SYSTEM SLOWS AND TAKES IT TIME
TO EXIT REGION BY END OF PERIOD. AS A CONSEQUENCE...POPS CONTINUE
UNTIL LATE IN FORECAST PERIOD.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
VFR CONDS XPCD TDA. SHWRS WILL SPREAD NEWD FROM SRN OH TWD THE ERN
OH TERMINALS...BUT THESE TOO WILL BE GENLY VFR. COMBINATION OF INCRG
MSTR AND COOLING OVNGT TEMPS LKLY WILL LEAD TO STRATUS LYR NR 1.5
KFT LATE TNGT THRU MRNG. UNCERTAINTY PERSISTS IN VSBY RESTRICTIONS
OWING TO PERSISTENT OVNGT WIND. IF WIND DIES...VSBY RESTRICTIONS
IN FOG WILL BE PSBL AT MANY TERMINALS.     UPDATE...KRAMAR

.OUTLOOK.../SUNDAY THROUGH WEDNESDAY/...
RESTRICTIONS IN DIURNALLY-GENERATED SCT SHWRS AND TSTMS WILL BCM
INCRGLY LKLY DURG THE FIRST HALF OF THE WK.
-- End Changed Discussion --

&&

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

&&

$$