-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 230813
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
413 AM EDT THU MAY 23 2013

.SYNOPSIS...
SHOWER AND THUNDERSTORM CHANCES WILL CONTINUE UNTIL A FRONT CROSSES
THE REGION THIS EVENING. MUCH COOLER WEATHER CAN BE EXPECTED FOR
THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

-- Changed Discussion --
CONVECTIVE THRESHOLDS WL BE CONSIDERABLY LOWER TDA AS THE UPR
TROF SLIDES EWD. WITH CONVECTIVE TEMPS PROGGED IN THE MID TO UPR
60S...AND WITH OVRALL ASCENT INCRSG...SCT MRNG SHWRS ARE EXPECTED
TO BECOME MORE NMBRS...HENCE POPS WERE INCRSD TO LIKELY NMBRS AND
TSTM MENTION WAS MAINTAINED.

DESPITE A RELATIVELY STRONG WIND FIELD...SEVERE POTENTIAL IS LOW
GIVEN THE OVRALL INSTABILITY LIMITATIONS.

NR TERM TEMPS WERE FORECAST USING TWEAKED LAMP GUIDANCE.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE CDFNT WL COMPLETE A SWEEP OF THE REGION TNGT...BUT CHC POPS
WERE MAINTAINED INTO FRIDAY GIVEN THE PRESENCE OF THE MID/UPR
TROF. BLDG HIGH PRES SHOULD SUPPRESS THOSE RESIDUAL CHCS BY FRIDAY AFTN.

ISSUE THEREAFTER IS OF TEMPS AS DVLPMNT OF A HIGH AMPLITUDE ERN
CONUS TROF SPPRTS STRNG COLD ADVCTN. SHOULD SFC WIND DIMINISH
SUFFICIENTLY...PTCHY FROST IS PSBL BY DAYBREAK SATURDAY.

SHORT TERM TEMPS WERE FORECAST USING A BLEND OF PERSISTENCE AND
SREF MEANS.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
DRY WEA IS EXPD THRU THE PERIOD WITH HIGH PRESSURE IN CONTROL. A
WRMFNT MAY APRCH BY MID WEEK BUT TOO MUCH UNCERTAINTY TO INCLUDE
ANY PCPN MENTION ATTM. TEMPS WL START OUT BLO AVG OVR THE
WEEKEND...THEN MODERATE TO SEASONAL LVLS AS HIGH PRESSURE SHIFTS E
OF THE AREA AND FLOW TURNS SRLY.

&&

.AVIATION /08Z TODAY THROUGH MONDAY/...
-- Changed Discussion --
DESPITE SCT SHWRS AND POCKETS OF MVFR THIS MRNG...MOST PORTS WL
EXPERIENCE VFR CONDITIONS. HOWEVER...MORE NMRS SHWRS AND SOME
TSTMS ARE ANTICIPATED THIS AFTN AS A CDFNT SLIDES CLOSER TO THE
UPR OH REGION. MVFR...AND ISOLD IFR VSBY SHOULD BE EXPECTED WITH
THE PCPN...AND MORE GENL MVFR CONDITIONS ARE EXPECTED WITH ACTUAL
PASSAGE OF THE FRONT THIS EVE.

.OUTLOOK.../TONIGHT THROUGH MONDAY/...
RESTRNS ARE LIKELY WITH SOME SHWRS INTO FRIDAY...BUT BLDG HIGH
PRES WL QUICKLY RTN VFR TO AREA PORTS BY AFTN. GENL VFR WL THEN
PERSIST INTO EARLY NEXT WEEK.
-- End Changed Discussion --

&&

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

&&

$$

15