An isolated severe thunderstorm developed along a stalled front over western Pennsylvania.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PBZ wrote it up.
An isolated severe thunderstorm developed along a stalled front over western Pennsylvania.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pittsburgh, PA wrote its last area forecast discussion before the first event at Jul 31, 4:26 PM EST, 14 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 526 PM EDT THU JUL 31 2008 .SYNOPSIS... ISOLATED SHOWERS OR THUNDERSTORMS MAY PERSIST THIS EVENING AS A WEAK COLD FRONT CONTINUES TO PROGRESS ACROSS THE UPPER OHIO VALLEY. ANOTHER RAIN CHANCE WILL COME WITH THE ADVANCE OF LOW PRESSURE LATE ON FRIDAY. && .NEAR TERM /THROUGH FRIDAY/... UPDATE TO EXPAND POPS MAINLY S OF PIT. SLIGHT CHANCE POPS NUMBERS WERE MAINTAINED IN THE FORECAST THROUGH THE EVENING FOR ZONES SOUTH/SOUTHWEST OF PIT AS SAGGING FRONT WILL CONTINUE TO WEAKLY FOCUS MOISTURE IN ADVANCE OF SHORTWAVE MOVING ACROSS THE MIDWEST TODAY. SURFACE HIGH PRESSURE WILL THEN BUILD ON FRIDAY AS NORTHWEST FLOW ALOFT AMPLIFIES...THUS DRY WEATHER MAY BE EXPECTED DURING THE DAY, BUT SHORTWAVE MOVING THROUGH THAT FLOW IS PROGGED TO GENERATE SOME SHOWERS AND THUNDERSTORMS ON FRIDAY EVE AND NIGHT. NEAR TERM TEMPERATURES WILL BE NEAR SEASONAL NORMS. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... MODEL TIMING OF FRIDAY NIGHT SHORTWAVE IS FOR SUFFICIENT EASTWARD PROGRESS BY EARLY SATURDAY TO CONSTRUCT POPS FOR A CONSERVATIVE SATURDAY MORNING/MIDDAY END TO PRECIP CHANCE. HIGH PRESSURE WILL THEN BUILD WITH TEMPERATURE PROJECTION AT, OR BELOW SEASONAL AVERAGES. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... SURFACE HIGH PRESSURE WILL SHIFT EASTWARD OFF THE ATLANTIC COAST ON MONDAY. COLD FRONT IS PROGGED TO SAG SOUTHWARD ACROSS THE GREAT LAKES ON TUESDAY AND THEN BECOME STRETCHED OUT ACROSS THE SOUTHERN PART OF OUR FORECAST AREA WEDNESDAY AND THURSDAY. SO EXPECT BEGINNING OF EXTENDED PERIOD TO BE DRY...WITH CHANCE POPS FOR SHOWERS AND THUNDERSTORMS STARTING LATE MONDAY AND CONTINUING THROUGH THURSDAY. DIFFICULT TO PINPOINT ANY RAIN FREE PERIODS AT THIS POINT...ALTHOUGH BEST CHANCE OF PRECIPITATION SHOULD OCCUR DURING TIMES OF MAXIMUM HEATING. TEMPERATURES ARE FORECAST TO BE A FEW DEGREES ABOVE THE NORM THROUGH WEDNESDAY AND THEN NEAR NORMAL THURSDAY. && .AVIATION /22Z THURSDAY THROUGH TUESDAY/... WIDELY SCATTERED SHOWERS CONTINUE TO FORM ACROSS THE FORECAST AREA THIS AFTERNOON AS LOW LEVELS REMAIN MOIST. EXPECT SHOWERS TO DISSIPATE BY EVENING AS SOLAR HEATING DECREASES AND LOW LEVELS DRY OUT A BIT. EXPECT MVFR/IFR VISIBILITIES IN PATCHY FOG AGAIN LATE TONIGHT AS SURFACE WINDS BECOME LIGHT. VFR WEATHER IS FORECAST FOR FRIDAY UNDER A WEAK SURFACE RIDGE. THE NEXT SHORTWAVE TROUGH WILL SWING ACROSS THE REGION...BRINGING SCATTERED SHOWERS AND STORMS WITH THE POTENTIAL FOR MVFR CONDITIONS LATE FRIDAY INTO EARLY SATURDAY. VFR CONDITIONS SHOULD RETURN FOR SUNDAY AND MONDAY UNDER HIGH PRESSURE. A COLD FRONT IS PROGGED TO SAG SOUTHWARD ACROSS THE GREAT LAKES ON TUESDAY ACCOMPANIED BY SCATTERED THUNDERSTORMS. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE PITTSBURGH PA 500 AM EDT THU JUL 31 2008 MDZ001-OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>023- 029>032-WVZ001>004-012-021>023-041-010900- GARRETT-TUSCARAWAS-CARROLL-COLUMBIANA-COSHOCTON-HARRISON- JEFFERSON OH-MUSKINGUM-GUERNSEY-BELMONT-NOBLE-MONROE-MERCER-VENANGO- FOREST-LAWRENCE-BUTLER-CLARION-JEFFERSON PA-BEAVER-ALLEGHENY- ARMSTRONG-INDIANA-WASHINGTON-WESTMORELAND-GREENE-FAYETTE-HANCOCK- BROOKE-OHIO-MARSHALL-WETZEL-MARION-MONONGALIA-PRESTON-TUCKER- 500 AM EDT THU JUL 31 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MARYLAND...EAST CENTRAL OHIO...NORTHWEST PENNSYLVANIA...SOUTHWEST PENNSYLVANIA...WEST CENTRAL PENNSYLVANIA...NORTHERN WEST VIRGINIA AND NORTHERN PANHANDLE OF WEST VIRGINIA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PITTSBURGH PA 521 PM EDT THU JUL 31 2008 PAZ021-029>032-WVZ003-312215- ALLEGHENY PA-FAYETTE PA-GREENE PA-OHIO WV-WASHINGTON PA-WESTMORELAND PA- 521 PM EDT THU JUL 31 2008 ...THUNDERSTORMS... THUNDERSTORMS WILL MOVE THROUGH THE FOLLOWING COUNTIES...FAYETTE...WASHINGTON...ALLEGHENY...WESTMORELAND...GREENE AND OHIO... AT 519 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR IN PITTSBURGH INDICATED STRONG THUNDERSTORMS 6 MILES NORTH OF CLAYSVILLE...MOVING SOUTHEAST AT 30 MPH. SOME LOCATIONS THAT WILL BE IMPACTED BY THESE STORMS INCLUDE... BELLE VERNON...BENTLEYVILLE...BROWNSVILLE...CALIFORNIA... CANONSBURG...CARMICHAELS...CHARLEROI...CLAYSVILLE...DONORA... MARIANNA...MASONTOWN...MCMURRAY...MONESSEN...MONONGAHELA AND NEMACOLIN THESE STORMS MAY PRODUCE WIND GUSTS TO 40 MPH...SMALL HAIL...AND VERY HEAVY RAIN. KEEP AN EYE TO THE SKY AND MOVE TO A SAFE PLACE IF THUNDERSTORMS APPROACH. PLEASE REPORT HAIL...STRONG WINDS OR WIND DAMAGE TO THE NATIONAL WEATHER SERVICE BY CALLING TOLL FREE...1-877-633-6772.
The Pittsburgh radar (KPBZ), 34 km away, was scanning. The volume nearest the first event began at 21:40 UTC.
1 thunderstorm wind. Local standard time, as filed.
Emergency management reported trees down along SR 844.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2008Every state in 2008This day in weather historyWarnings in Pennsylvania, July 2008
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 126226.