625
FXUS61 KPBZ 120633
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
233 AM EDT WED AUG 12 2026
WHAT HAS CHANGED
THE HEAVY RAINFALL/FLOODING THREAT IS LOWER FOR TODAY (WITH THE
FLOOD WATCH TO BE CANCELLED EARLY), BUT THE CHANCE FOR ISOLATED
DAMAGING WIND/LARGE HAIL EVENTS IS A BIT HIGHER, MAINLY NORTH
OF PITTSBURGH.
KEY MESSAGES
1) DAILY CHANCES OF SHOWERS AND THUNDERSTORMS CONTINUE THROUGH
THURSDAY. THE FLOODING THREAT IS LOWER FOR TODAY, BUT MAY
INCREASE FOR AREAS SOUTH OF PITTSBURGH ON THURSDAY. ISOLATED
SEVERE STORMS ARE POSSIBLE NORTH OF PITTSBURGH THIS AFTERNOON
AND EVENING.
2) THE NEXT BEST CHANCE OF NUMEROUS SHOWERS AND THUNDERSTORMS
ARRIVES SUNDAY. A BREAK IN THE PATTERN MAY FOLLOW EARLY NEXT
WEEK.
DISCUSSION
KEY MESSAGE 1...
A (THANKFULLY) QUIET NIGHT IS IN PROGRESS, AS THE ENVIRONMENT IS
GENERALLY STABLE WITH NO PRESENT FORCING FOR ASCENT. AS SUCH,
LOW CLOUDS AND FOG ARE DEVELOPING AND SHOULD PLAGUE THE CWA INTO
THE POST-SUNRISE HOURS.
THE EFFECTIVE OUTFLOW BOUNDARY/FRONT REMAINS RELATIVELY FAR TO
THE SOUTH AND WEST OF THE REGION, AS A RESULT OF THE RECENT
PARADE OF THUNDERSTORM COMPLEXES. THE ONGOING CONVECTION IN
EASTERN IN/WESTERN OH IS EVIDENCE OF THIS BOUNDARY'S POSITION.
EXPECT THIS GENERAL REGIME TO CONTINUE THROUGH TODAY AND
TONIGHT, AS HREF/CAMS CONTINUE TO SHOW THE BULK OF CONVECTIVE
ACTIVITY MORE CLOSELY TIED TO THIS BOUNDARY. STILL, SOME
SCATTERED SHOWERS AND STORMS ARE POSSIBLE DURING THE LATER
AFTERNOON AND EVENING, ONCE WEAK CAPPING IS OVERCOME IN AN
ENVIRONMENT WITH AROUND 1000 J/KG OF MLCAPE. NORTH OF
PITTSBURGH, SHEAR OF 30-35 KNOTS MAY SUPPORT SOME STORM
ORGANIZATION, SUPPORTING ISOLATED DAMAGING WIND AND HAIL
THREATS. ANY SUCH ACTIVITY SHOULD MOSTLY FADE AWAY DURING THE
LATER EVENING HOURS.
THE HEAVY RAIN THREAT APPEARS LOWER TODAY, GIVEN THE FURTHER
WEST FAVORED TRACK FOR CONVECTIVE COMPLEXES AND RELATIVELY
ELONGATED HODOGRAPHS PROMOTING FASTER STORM MOTION. HREF/REFS
90TH PERCENTILE QPF THROUGH 8 PM THURSDAY IS AN INCH OR LOWER
FOR MOST AREAS, INCLUDING THE AREA OF THE CURRENT FLOOD WATCH
THAT EXPIRES AT 8 AM. AS SUCH, THIS WATCH WILL LIKELY BE
CANCELLED A FEW HOURS EARLY.
FOR THURSDAY, SEVERE CHANCES APPEAR TO ONCE AGAIN BE LIMITED,
WITH SUFFICIENT SHEAR/INSTABILITY FOR ISOLATED DAMAGING
WIND/HAIL THREATS AT MOST. THE FAVORED ZONE FOR CONVECTIVE
COMPLEXES SHOULD REMAIN WEST OF THE AREA, BUT THE RICHER
RESERVOIR OF MOISTURE/INSTABILITY MAY EDGE CLOSER, RESULTING IN
HIGHER RAIN CHANCES TO THE SOUTH OF PITTSBURGH. THIS WILL NEED
TO BE MONITORED - IF THE HEAVY RAIN THREAT IN THIS AREA
INCREASES, A NEW FLOOD WATCH MAY BE NECESSARY.
KEY MESSAGE 2...
THEREAFTER THE WNW FLOW PATTERN CONTINUES WITH NEARLY DAILY
THUNDERSTORM CHANCES, ALTHOUGH A BREAK MAY BE SEEN SATURDAY.
SUNDAY STILL APPEARS TO HAVE THE HIGHER PROBABILITIES OF A
CONCENTRATED AREA OF PRECIPITATION GIVEN THE APPROACH OF A COLD
FRONT. NON-ZERO SEVERE WEATHER AND HEAVY RAINFALL THREATS WILL
PERSIST. A BREAK IN THE PATTERN MAY FINALLY ARRIVE AFTER THAT
FRONT EARLY NEXT WEEK AS SURFACE HIGH PRESSURE MAKES A MORE
DEFINITIVE PUSH INTO THE UPPER OHIO VALLEY.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
A STABLE ENVIRONMENT IS IN PLACE ACROSS THE REGION, WITH A
WELCOME BREAK FROM CONVECTION. WITH LOW-LEVEL MOISTURE IN PLACE,
IFR TO LIFR STRATUS/FOG HAS ALREADY DEVELOPED AT SEVERAL
TERMINALS AND IS EXPECTED TO BECOME A BIT MORE WIDESPREAD AS
SUNRISE APPROACHES. CEILINGS SHOULD LIFT TO MVFR BY LATE
MORNING, AND TRANSITION INTO A CU/STRATOCU LAYER AND RETURN TO
VFR LEVELS BY AFTERNOON.
MODELS CONTINUE TO SHOW A WEAK SHORTWAVE TRACKING ACROSS THE
EASTERN GREAT LAKES/UPPER OHIO VALLEY DURING THE LATE AFTERNOON
AND EARLY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS MAY BE
THE RESULT. TERMINALS NORTH OF PIT (MAINLY FKL/DUJ) MAY BE
SLIGHTLY MORE FAVORED FOR IMPACTS, BUT CONFIDENCE IN EXACT
TIMING AND PLACEMENT REMAINS RELATIVELY LOW, AND THUS CONTINUED
WITH PROB30 MENTIONS AT ALL TAF SITES.
OUTLOOK...
PATCHY MORNING FOG AND STRATUS IS POSSIBLE THURSDAY MORNING. A
WAVE OF LOW PRESSURE TRACKING ALONG A STATIONARY FRONT WILL
INCREASE SHOWER/THUNDERSTORM CHANCES THURSDAY INTO THURSDAY
NIGHT. VFR RETURNS FRIDAY NIGHT THROUGH SATURDAY NIGHT UNDER
HIGH PRESSURE. RESTRICTION POTENTIAL RETURNS WITH SHOWER AND
THUNDERSTORM CHANCES ON SUNDAY WITH THE APPROACH OF A COLD
FRONT.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...CL
AVIATION...CL
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page