An isolated low-topped thunderstorm produced wind damage near Wellsboro in Tioga county during the late evening.
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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 CTP wrote it up.
An isolated low-topped thunderstorm produced wind damage near Wellsboro in Tioga county during the late evening.
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 State College, PA wrote its last area forecast discussion before the first event at Sep 21, 10:30 PM EST, 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 1130 PM EDT FRI SEP 21 2012 .SYNOPSIS... A DYING COLD FRONT WILL BECOME NEARLY STATIONARY ACROSS CENTRAL PENNSYLVANIA TONIGHT. A STRONGER COLD FRONT WILL CROSS THE REGION SATURDAY BRINGING MUCH COOLER AND DRIER AIR FOR SATURDAY NIGHT AND SUNDAY. A LARGE AREA OF HIGH PRESSURE WILL BUILD INTO THE COMMONWEALTH FOR THE FIRST HALF OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... EVENING RADAR LOOP CONTINUES TO SHOW A FEW SHRA DEVELOPING ALONG REMNANTS OF STALLED COLD FRONT OVER CENTRAL PA...RUNNING FROM ARND AOO TO UNV AND ELM AT 01Z. ANY SCATTERED SHRA ASSOCIATED WITH OUR DYING FRONT WILL DWINDLE WITH LOSS OF HEATING LATER THIS EVENING. FOCUS SHIFTS TOWARD NW PA FOR THE REST OF THE NIGHT...AS POTENT SHORTWAVE AND ASSOC SFC LOW LIFT ACROSS THE EASTERN GRT LKS. WAA AHEAD OF THIS FEATURE ALREADY PRODUCING AN AREA OF RAIN ACROSS THE NW MTNS AT 01Z. LATEST MDL-DERIVED RADAR SUGGESTS THIS BATCH OF WWA RAIN LIFTS NORTH OF THE BORDER BY ARND 03Z. HOWEVER...AS POTENT SHORTWAVE LIFTS ACROSS LK ERIE BTWN 05Z- 08Z...EXPECT THE LIKELIHOOD OF HEAVIER SHOWERS AND POSSIBLE THUNDER ACROSS OUR NW ZONES. MDL DATA INDICATES WING SPEEDS AT 8H WITH POWERFUL LL JET NR 60KTS ACROSS THE NW ZONES OVERNIGHT. HAVE INCREASED SFC WIND SPEEDS A BIT. HOWEVER...MDLS INDICATE LOW LVLS WILL BE SUFFICIENTLY STABLE TO PRECLUDE STRONG GUSTS FROM REACHING GROUND LVL. HAVE LOWERED POPS CONSIDERABLY LATE TONIGHT...WHEN ALL LG SCALE FORCING WITH SHORTWAVE PASSES NORTH THE AREA. STILL...WILL MAINTAIN A CHC OF SHOWERS ACROSS THE NW MTNS IN ASSOCIATION WITH TRAILING COLD FRONT...WHICH SHOULD BE ENTERING THE NW MTNS BY ARND 12Z. ACROSS THE EASTERN HALF OF THE CWA...LOOKS LIKE A RELATIVELY QUIET NIGHT WITH LITTLE CHC OF ANY PRECIP. MDLS DO INDICATE THAT A MOIST...SSERLY FLOW...COMBINED WITH DIURNAL COOLING...COULD PRODUCE SOME LOW CLOUDS /WITH POSS FOG ON THE RIDGES/ ACROSS THE POCONOS...INCLUDING SCHUYLKILL AND SULLIVAN CO. CURRENT READINGS AND LAMP GUIDANCE CONTINUE TO INDICATE LOW TEMPS TONIGHT MAINLY IN THE 50S. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... HAVE REDUCED CHC OF ANY RAIN MARKEDLY BTWN 12Z-18Z...AS MDL DATA SHOWING A LACK OF UPPER LVL SUPPORT FOR COLD FRONT...WHICH WILL BE PUSHING THRU THE CENTRAL MTNS BY LATE AM. BEST CHC OF SHRA /AND TSRA/ DEFINITELY APPEARS TO BE LATE IN THE DAY ACROSS EASTERN PA...WHERE DIURNAL HEATING/DESTABILIZATION AND APPROACH OF NEXT SHORTWAVE SHOULD CREATE A MORE ACTIVE FROPA OVER OUR EXTREME EASTERN ZONES. SPC HAS OUTLOOKED EASTERN PA FOR A SLIGHT RISK. INSTABILITY WILL BE MODEST WITH LAPSE RATES ACTUALLY FCST TO DECREASE THROUGHOUT THE DAY. HOWEVER WITH THE APPROACH OF A SHARP UPPER TROUGH...SHEAR WILL BECOME MORE ROBUST AND COULD HELP ORGANIZE ANY CONVECTION THAT MANAGES TO FORM IN THE MARGINALLY UNSTABLE PRE-FRONTAL AIRMASS. IT WILL BE ANOTHER MILD DAY OVER MUCH OF THE EASTERN PART OF THE FCST AREA...WITH CHILLIER AIR SPILLING IN BEHIND THE FRONT KEEPING THE NW MOUNTAINS IN THE 60S. ELSEWHERE THE 70S LOOK LIKE A DECENT BET...WITH L80S FOR THE LOWER SUSQ VALLEY. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... COOL POSTFRONTAL WEATHER REGIME TO COVER THE COMMONWEALTH ON SUNDAY AS SPRAWLING UPPER LOW EXTENDING FROM THE NORTHERN GREAT LAKES TO HUDSON BAY SPINS AND LIFTS SLOWLY NORTHEASTWARD. SUNDAY AND MONDAY WILL BE BELOW NORMAL TEMPERATURE WISE AS THE MEAN UPPER TROF PERSISTS OVER EASTERN CANADA KEEPING COOL AIR OVER THE GREAT LAKES AND NORTHEAST. IT WILL BE CLOUDY FOR MUCH OF WESTERN AND NORTHERN PA...WITH A CHC OF SHOWERS EXTENDING INTO THE CENTRAL MOUNTAINS. LATEST GUIDANCE SUGGESTS ANOTHER FAIRLY VIGOROUS UPPER TROF WILL CROSS THE REGION SUNDAY NIGHT AND MONDAY BRINGING ANOTHER PERIOD OF SCATTERED SHOWERS. ZONAL FLOW BREAKS THROUGH LATER MONDAY AND TUESDAY WITH MODERATING 850 MB TEMPERATURES AND HIGH PRESSURE BUILDS ENE FROM THE CENTRAL TENNESSEE RIVER VALLEY. TEMPS WILL MODERATE FURTHER ON WEDNESDAY AHEAD OF A FRONTAL SYSTEM DROPPING SOUTHWARD FROM THE GREAT LAKES. THE FRONT SHOULD SAG AND STALL SOUTH OF THE MASON DIXON LINE LATE THIS WEEK...WITH COOLER AN DRIER WEATHER TO THE NORTH. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... MINOR CHANGES MADE TO 03Z TAFS. EARLIER DISCUSSION BELOW. PUSH OF DRY AIR OVER FAR WESTERN NY AND SOUTHERN CANADA ABOUT AS FAR SE AS IT IS GOING TO GO. COULD SEE THE BOUNDARY JUST WEST OF THE RADAR SITE EARLIER. SHOWERS AND STORMS CONTINUE TO FORM NEARBY AND LIFT NE. DECENT ELEVATED INSTABILITY AND DIRECTIONAL SHEAR...WILL CONTINUE TO MONITOR STORMS. ADDED LLWS TO BFD...AND ALSO IPT. BFD NEAR THE LLJ BY 06Z... WHILE IPT OFTEN GETS A GUSTY SE WIND IN THE EVENING AND EARLY OVERNIGHT. EXPECT MOST AREAS TO BE VFR BY LATE MORNING ON SAT. HAVE TO WATCH FOR STRONG TO SEVERE STORMS EAST OF THE MOUNTAINS. THE WAY THE WINDS ARE BACKED ACROSS SOUTHERN OH AND IN THIS EVENING MAKES MYSELF THINK TWICE ABOUT HOW ACTIVE SATURDAY COULD BE. DRY SLOT WORKS IN FOR LATER SATURDAY INTO EARLY SUNDAY...BUT COLD AIR ALOFT WILL LIKELY TRIGGER SOME SHOWERS LATER SUNDAY... PERHAPS INTO MONDAY MORNING. AS THE HIGH MOVES EAST AND SOUTH OF THE AREA LATE MONDAY INTO TUE. A WARMER SW FLOW OF AIR WILL SET IN FOR MID WEEK. OUTLOOK... SUN...MAINLY VFR BUT MVFR CONDITIONS POSSIBLE ACROSS THE HIGHER MTNS WITH A FEW SHOWERS. MON...BECOMING VFR...AS HIGH PRESSURE BUILDS ACROSS THE AREA. TUE-WED...VFR...WITH A FEW SHOWERS POSS LATER TUES INTO WED ACROSS WESTERN MTNS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...DEVOIR AVIATION...MARTIN
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 316 PM EDT FRI SEP 21 2012 PAZ004>006-010>012-017>019-024>027-033>035-037-041-045-221930- WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD- NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN- SOMERSET-BEDFORD-FULTON-TIOGA-NORTHERN LYCOMING-SOUTHERN CLINTON- 316 PM EDT FRI SEP 21 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...THIS AFTERNOON AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ028-036-042-046-049>053-056>059-063>066-221930- JUNIATA-FRANKLIN-SULLIVAN-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND- ADAMS-YORK-LANCASTER- 316 PM EDT FRI SEP 21 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...THIS AFTERNOON AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. A COLD FRONT WILL MOVE OVER THE SUSQUEHANNA VALLEY DURING THE MID TO LATE AFTERNOON HOURS. SCATTERED STRONG TO POTENTIALLY SEVERE THUNDERSTORMS WILL DEVELOP ALONG AND JUST AHEAD OF THE COLD FRONT. ISOLATED...DAMAGING WIND GUSTS...AND LARGE HAIL ARE THE MAIN SEVERE WEATHER THREAT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The State College radar (KCCX), 111 km away, was scanning. The volume nearest the first event began at 03:41 UTC.
1 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds estimated near 80 mph knocked down several trees and caused a partial roof collapse on Niles Road just east of Wellsboro. One woman was injured as a result of the damage.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2012Every state in 2012This day in weather historyWarnings in Pennsylvania, September 2012
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: 404695.