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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 181826
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
226 PM EDT SAT MAY 18 2013

.SYNOPSIS...
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.

&&

.NEAR TERM /THROUGH SUNDAY/...
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.

DECAYING UPR LOW WILL LINGER ON SUN WITH VERY MOIST AMS BCMG
BETTER SITUATED ACRS FCST AREA. RGN WILL BE WEAKLY CAPPED...WITH
SHWRS AND TSTMS XPCD TO INCR IN CVRG WITH ONLY MODEST HEATING
REQUIRED. MAXIMA WILL BE SIMILAR TO THOSE TDA SUBJECT TO DEG OF
CLD CVR THAT RMNS SUN MRNG.    UPDATE...KRAMAR

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
-- Changed Discussion --
A WARM FRONTAL SYSTEM WILL PUSH NORTH OF THE DISTRICT LATE SUNDAY
INTO MONDAY REDUCING THE THREAT OF SHOWERS...BUT PRODUCING WARMER
TEMPERATURES FOR MONDAY AFTERNOON. A CHANCE OF DIURNAL SHOWERS CAN BE
EXPECTED MONDAY AFTERNOON...BUT MAINLY IN THE SOUTH.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A SLOW MOVING COLD FRONT WILL PUSH INTO THE OHIO WEDNESDAY AND
MOVE ACROSS THE FORECAST AREA ON THURSDAY. AHEAD OF THE FRONT
WARMING TEMPERATURES CAN BE EXPECTED ALONG WITH AN INCREASING
CHANCE OF SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON AND
EVENING HOURS. WEDNESDAY NIGHT INTO THURSDAY WILL BE THE MOST
ACTIVE PERIOD OF SHOWERS AND THUNDERSTORMS. THE COLD FRONT WILL
MOVE SLOWLY EAST OF THE DISTRICT FRIDAY WITH A CHANCE OF SHOWERS
AND COOLER TEMPERATURES EXPECTED INTO SATURDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
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.

&&

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

&&

$$