080
FXUS61 KPBZ 251733
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
133 PM EDT TUE AUG 25 2026
WHAT HAS CHANGED
UPDATED AVIATION DISCUSSION FOR 18Z TAFS. TOUCHED UP KEY
MESSAGE.
KEY MESSAGES
1) SURROUNDED BY DRY DAYS, THURSDAY FEATURES ISOLATED TO
SCATTERED THUNDERSTORMS OFFERING LOW PROBABILITY SEVERE THREAT.
DISCUSSION
KEY MESSAGE 1...
SURFACE HIGH PRESSURE AND HEIGHT RISES FAVOR DRY WEATHER WITH
SEASONABLE TEMPERATURE THROUGH WEDNESDAY NIGHT.
THE NEXT UPPER TROUGH IS CURRENTLY OVER SOUTHERN MANITOBA. AFTER
MOVING ACROSS THE WESTERN GREAT LAKES WEDNESDAY, IT WILL SLOWLY
CROSS THE OHIO RIVER VALLEY THURSDAY THROUGH FRIDAY MORNING AND
INCREASE SHOWER/THUNDERSTORM CHANCES. MODELS SUGGEST THAT THE
LACK OF A STRONG SURFACE BOUNDARY AND WEAKER JET ASCENT MAY
LIMIT THE AREAL STORM COVERAGE IN WHAT OTHERWISE WOULD BE A MORE
WIDESPREAD, HIGH PROBABILITY RAIN CHANCE. STORMS THAT DO FORM
SHOULD EXPERIENCE MODEST CAPE (AROUND 1000-1200 J/KG) AND WEAK
SHEAR (AROUND 20KTS), JUST ENOUGH TO CREATE NON- ZERO SEVERE
HAZARD RISK (MAINLY DAMAGING WIND). THE BEST COMBINATION OF
THESE ENVIRONMENTAL FACTORS AND STORM COVERAGE IS GENERALLY EAST
OF I-79, WHERE SPC HAS HIGHLIGHTED A MARGINAL RISK IN THE DAY 3
OUTLOOK.
LINGERING TROUGHING (SFC/ALOFT) AND MOISTURE MAY FOSTER A FEW
ISOLATED SHOWERS/THUNDERSTORMS FRIDAY AFTERNOON AMID PEAK
HEATING. OTHERWISE, SURFACE HIGH PRESSURE BUILDING IN FROM THE
NW AND EVENTUAL HEIGHT RISES LEND TO DRIER WEATHER PLUS
SEASONABLE TEMPERATURE FOR FRIDAY INTO THE WEEKEND. ENSEMBLE
MODEL VARIABILITY IS LARGER TO START THE NEXT WEEK BUT
SCENARIOS EXISTS SEVERE-FAVORING UPPER LEVEL PATTERNS WORTH
MONITORING IN THE COMING DAYS.
AVIATION /18Z TUESDAY THROUGH SUNDAY/
AS 1020 MB SURFACE HIGH STARTS TO BUILD OVERHEAD THE NORTHWEST
FLOW HAS WEAKENED AND LAKE INDUCED CLOUD COVER IS GRADUALLY
BREAKING UP OVER THE CENTRAL AND NORTHERN TAF SITES. VFR
STRATOCUMULUS DECK SHOULD BE GONE BY SUNSET.
THE HIGH WILL BE OVERHEAD TONIGHT, WITH CLEAR SKIES AND CALM
WINDS RESULTING IN RIVER VALLEY FOG. MVFR TO PERHAPS IFR
VISIBILITY IS POSSIBLE. PROBABILITY OF MVFR VISIBILITY FROM FOG
FOR 04 TO 12Z TONIGHT IS 20-40%, WITH IFR IN THE 10-20% RANGE.
WHATEVER FOG FORMS TONIGHT WILL BURN OFF FAST WEDNESDAY MORNING
BY 13-14Z WITH VFR AND WINDS TURNING TO LIGHT SOUTHERLY.
OUTLOOK...
THE NEXT WIDESPREAD RAIN CHANCES AND POTENTIAL FOR RESTRICTIONS ARRIVE
THURSDAY INTO FRIDAY. SATURDAY AND SUNDAY SHOULD BE DRY UNDER
HIGH PRESSURE WITH POTENTIAL FOR RIVER VALLEY FOG RESTRICTIONS
ROUGHLY 04-12Z EACH NIGHT.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...CRAVEN
AVIATION...CRAVEN
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