Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KPBZ 301022
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
622 AM EDT SUN AUG 30 2015

.SYNOPSIS...
ISOLATED TO SCATTERED RAIN SHOWERS THROUGH SUNDAY AS A WEAKENING
AREA OF LOW PRESSURE APPROACHES THE UPPER OHIO VALLEY REGION.

&&

.NEAR TERM /THROUGH TONIGHT/...
LATEST MOSAIC RADAR IMAGERY SHOWING A FAIRLY WELL CONGEALED MASS OF
SHOWERS MOVING QUICKLY THROUGH WESTERN PENNSYLVANIA. THIS RAIN
WILL CONTINUE TO FOLLOW THE MODEST UPPER SUPPORT IN THE FORM OF
UPPER-LEVEL DIVERGENCE FROM THE RIGHT ENTRANCE REGION OF THE
300MB JET. EXPECTING A BREAK IN RAIN CHANCES BY MID-MORNING
AREAWIDE.

A BIT OF A TRANSITION PERIOD FOLLOWS AS THE WEAK FRONT CONTINUES
TO WASH OUT...AND RESIDUAL LOW-LEVEL MOISTURE REMAINS. DESPITE
THE PRESENCE OF ANY ORGANIZED ASCENT...WEAK MESOSCALE IMPULSES
ALONG THE LINGERING BOUNDARY COULD COMBINE WITH MOISTURE TO
PRODUCE DISORGANIZED SHOWERS AND THUNDERSTORMS SUNDAY AFTERNOON.
WILL CONTINUE TO CARRY CHANCE/SCATTERED WORDING THROUGH THE
EVENING. ALMOST ALL MOISTURE ABOVE 700MB EVACUATES THE AREA THIS
AFTERNOON/EVENING...AS THE WEAK UPPER TROF PULLS AWAY. ADDITIONAL
MOISTURE WILL ARRIVE ACROSS OUR SOUTH...PULLED UP BY SOUTHERLY
FLOW THROUGH THE SOUTHEASTERN US. THIS SHOULD RESULT IN LITTLE
MORE THAN ISOLATED SHOWERS HEADING INTO THE SUNDAY OVERNIGHT
PERIOD.
TAX

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
A VORTICITY LOBE WILL LIFT FROM THE SOUTHERN APPALACHIANS TOWARDS
THE MIDATLANTIC COAST ON MONDAY. THE SOUTHERN PORTION OF THE CWA
WILL BE SKIMMED BY THIS MIDLEVEL SUPPORT. MOISTURE AND INSTABILITY
WILL BE BARELY SUFFICIENT FOR SLIGHT CHANCE POPS FROM PIT ON
SOUTH. PROXIMITY TO VORT LOBE PLUS TERRAIN MAY ALLOW FOR A BIT
BETTER COVERAGE ALONG THE SOUTHEASTERN RIDGES. DEPARTURE OF
DISTURBANCE PLUS LOSS OF HEATING WILL END PRECIPITATION CHANCES BY
00Z TUESDAY.

THEREAFTER...H500 RIDGING WILL TAKE CONTROL OF THE EASTERN PART OF
THE COUNTRY AND HOLD ON FOR AN EXTENDED PERIOD. MIDLEVEL CAPPING
APPEARS MORE LIKELY ON TUESDAY...AND FOR NOW HAVE ONLY KEPT SLIGHT
CHANCE POPS ALONG THE RIDGES...WHERE ELEVATED HEAT SOURCE EFFECT
MAY HELP TO PRODUCE A SHRA OR TSRA ON AN ISOLATED BASIS. FOR
WEDNESDAY...A WEAK SHORTWAVE OVER THE OHIO VALLEY...EMBEDDED IN
THE GENERAL RIDGING PATTERN...MAY ALLOW CAPPING TO BE OVERCOME
SUFFICIENTLY FOR ISOLATED CONVECTION. EACH NIGHTTIME PERIOD SHOULD
BE MOSTLY DRY.

TEMPERATURES WILL OF COURSE BE ABOVE NORMAL IN THIS PATTERN.
GENERALLY BLENDED MOSGUIDE WITH PREVIOUS VALUES FOR THE FORECAST.
WOULD EXPECT SOME READINGS AT OR JUST OVER THE 90 DEGREE LEVEL BY
WEDNESDAY AFTERNOON.
CL

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
NO CHANGES TO THE OVERALL PATTERN ARE EXPECTED...WITH THE EASTERN
RIDGE HOLDING FIRM. WITH THE RIDGE AXIS STILL TO THE WEST ON
THURSDAY...AN AREAWIDE SLIGHT CHANCE STILL LOOKS APPROPRIATE. THE
SPRAWLING UPPER HIGH WILL DRIFT EASTWARD WITH TIME THOUGH...SUCH
THAT THE RIDGES WOULD BE FAVORED MAINLY FOR DIURNAL ACTIVITY FOR
FRIDAY AND SATURDAY. BY SUNDAY...WITH THE CENTER OF THE RIDGE JUST
TO THE EAST...AN IMPROVED MOISTURE FEED MAY SUPPORT ACTIVITY
AREAWIDE ONCE AGAIN. LITTLE ORGANIZATION IS FORESEEN THROUGHOUT
THE EXTENDED PERIOD...WITH OVERALL PRECIPITATION TOTALS REMAINING
FAIRLY LOW. ABOVE NORMAL TEMPERATURES IN THE 80S TO AROUND 90 WILL
BE FEATURED EACH DAY.
CL

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
UPPER-LEVEL TROF MOVING ACROSS REGION...RESULTING IN SHOWERS
QUICKLY MOVING THROUGH WESTERN PENNSYLVANIA. SOME MVFR
RESTRICTIONS ARE POSSIBLE FOR FKL/DUJ THROUGH MID-MORNING...BUT
IMPROVEMENT TO VFR IS EXPECTED FOR ALL TERMINALS FOR THE BULK OF
THE DAY.

CONTINUED GENERAL VFR CIGS LATER TODAY WITH ONLY SCATTERED
SHOWERS AT BEST WITH WEAK UPPER SUPPORT AND SHALLOW MOISTURE.
ADDITIONAL RESTRICTIONS ARE POSSIBLE WITH FOG DEVELOPMENT IN THE
PRE-DAWN HOURS MONDAY. WINDS WILL BE LIGHT MAINLY FROM THE WEST.
TAX

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
GENERAL VFR EXCEPT FOR POSSIBLE PATCHY MORNING FOG THE REMAINDER OF
THE WEEK.

&&

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

&&

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.