127 
FXUS61 KPBZ 201125 CCA
AFDPBZ

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE PITTSBURGH PA
724 AM EDT THU JUN 20 2013

.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE PLENTY OF SUNSHINE AND A GRADUAL
INCREASE IN TEMPERATURES INTO THE WEEKEND. A FEW AFTERNOON SHOWERS
OR A THUNDERSTORM COULD BE SCATTERED ABOUT OVER THE MOUNTAINS
TODAY THROUGH SATURDAY WITH THE POSSIBILITY OF SOME WIDELY
SCATTERED THUNDERSTORMS AROUND THE REGION BY SUNDAY AFTERNOON.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
ONLY CHANGE WAS A TWEAK IN TEMP TREND FIRST 12 HOURS.
PREVIOUS DISCUSSION FOLLOWS...
HIGH PRESSURE RIDGE WILL KEEP MOSTLY CLEAR SKIES ACROSS THE
FORECAST AREA THROUGH TODAY. MODEL GUIDANCE SUGGESTS THAT LOW
LEVEL MOISTURE ALONG THE RIDGES OF PA/WV/MD MAY REMAIN IN TACT.
NAM AND GFS SUGGEST AT LEAST SOME WEAK INSTABILITY. KEPT POPS
THERE BELOW SLIGHT CHANCE THRESHOLD...WITH STRONG SUBSIDENCE IN
PLACE LIKELY TO KEEP CONVECTION CAPPED.

TEMPERATURES THURSDAY KEPT RIGHT AROUND SEASONAL AVERAGES AND CLOSE
TO MOS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
H5 RIDGE HOLDING THROUGH THIS PERIOD. A CONTINUATION OF POSSIBLE
WIDELY SCATTERED SHOWERS OR A THUNDERSTORM OVER THE HIGHER TERRAIN
WITH LESS ENERGY NEEDED TO BREAK CAP GIVEN ELEVATED TERRAIN. BOTH
HRRR AND HIRES WINDOW SUGGESTING SOME WIDELY SCATTERED ACTIVITY.
CALIBRATED THUNDERSTORM FIELDS FROM SREF ALSO SUGGESTING SAME EVEN
INTO SATURDAY. H5 HEIGHTS CONTINUE ON THE RISE WITH 850 TEMPS OF
16+ PUSHING IN BY SATURDAY. GRADUALLY INCREASED SFC TEMPS TO UPPER
80S TO AROUND 90. WITH SIGNIFICANT SUBSIDENCE THINKING IS THAT
CHANCE WIDELY SCATTERED PRECIP RATHER MINIMAL FOR SATURDAY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
H5 RIDGE CONTINUES TO BUILD THROUGH SUNDAY AND FINALLY FLATTENS OUT
INTO MONDAY. SFC RIDGE STILL HANGING TOUGH BUT AN INCREASE IN
HUMIDITY AND CLOUDS. SEVERAL SHORT WAVES IN THE STRONGER H5 FLOW
TO OUR NORTH TRY AND PULL WEAK SURFACE TROUGHS ACROSS REGION AND
WENT SLIGHT CHANCE ON SUNDAY AND SUNDAY EVENING AND THEN BROUGHT
CHANCE POPS IN THROUGH THE END OF THIS PERIOD. SEEMINGLY NO REAL
SIGNIFICANT/STRONG DYNAMICS UNTIL MIDWEST SYSTEMS EJECTS LATE IN
PERIOD (LATE WEDNESDAY INTO THURSDAY). HOWEVER, THIS AT END OF
PERIOD AND PLENTY OF UNCERTAINTY AT THIS POINT.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE OVER THE GREAT LAKES WILL KEEP SKIES CLEAR AND WINDS
LIGHT THRU THE PERIOD.

OUTLOOK.../THURSDAY NIGHT THROUGH MONDAY/... 
GENERAL VFR CONDITIONS ARE EXPECTED TO CONTINUE...ALTHOUGH WARMER
AND MORE HUMID AIR WILL BRING THE CHANCE FOR AFTN/EVE TSTMS SUN
AND MON.

&&

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

&&

$$