Severe thunderstorms produced isolated wind damage, large hail and flash flooding across portions of the mid and lower Susquehanna Valley during the afternoon.
Every event with a place to put it. Tap one for its entry below.
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.
Severe thunderstorms produced isolated wind damage, large hail and flash flooding across portions of the mid and lower Susquehanna Valley during the afternoon.
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 Aug 4, 9:53 AM EST, 1 hour 52 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 1053 AM EDT SAT AUG 4 2012 .SYNOPSIS... AN APPROACHING COLD FRONT WILL BRING AN INCREASE IN HUMIDITY AND THE CHANCE OF SHOWERS AND STORMS THROUGH SUNDAY...BEFORE DRIER AIR BUILDS IN FOR EARLY NEXT WEEK. OVERALL THE PATTERN FOR EASTERN NORTH AMERICA IS IN TRANSITION WITH THE EXPECTED DEVELOPMENT OF A BROAD TROUGH OVER THE NEXT 4 TO 8 DAYS. && .NEAR TERM /THROUGH TONIGHT/... MOIST SOUTHWESTERLY FLOW WILL CONTINUE TO INCREASE AHEAD OF A COLD FRONT ENTERING THE GR LAKES. THIS WILL PROVIDE INCREASING CHANCES FOR SHOWERS/STORMS...ESPECIALLY THIS AFTERNOON AND EVENING. MUCH OF THE MORNING AND POSSIBLY EVEN INTO THE EARLY AFTERNOON HOURS SHOULD STAY PARTLY TO MOSTLY SUNNY AND DRY BEFORE WE REACH CONVECTIVE TEMPS AND START TO COOK UP SCATTERED SHOWERS AND STORMS. SREF POPS FOR LATER THIS AFTERNOON AND EVENING RANGE FROM CHANCE OVER THE NORTH TO CATEGORICAL OVER THE SOUTH...PROBABLY TYPICALLY OVERDONE BY THE SREF. CURRENT HRRR SHOWING PRECIPITATION FORMING OVER THE LAUREL HIGHLANDS BY 18Z. THE SREF AND GEFS HAVE INCREASED PWAT ANOMALIES OVER THE AREA. COUPLE THIS WITH TEMPERATURES IN THE UPPER 80S AND LOWER 90S...AND DECENT SOUTHEASTERLY FLOW...EXPECT DIURNAL CONVECTION THIS AFTERNOON AND THROUGH THE FIRST HALF OF THE EVENING. MODELS SOW IT SPREADING ACROSS CENTRAL PA BEFORE MOVING EASTWARD. HAVE INCREASED POPS ACCORDINGLY. THESE SHOWERS AND STORMS SHOULD BE MORE DIURNALLY DRIVEN THAN LARGER SYNOPTIC FORCING...HOWEVER A 500MB SHORTWAVE COULD ALLOW FOR A STRONG ENOUGH PV ANOMALY TO CONTINUE SHOWERS WELL INTO THE EVENING OVER THE SOUTHEAST. ANY PRECIP SHOULD BE DONE BY 06-09Z TONIGHT. PATCHY FOG AHEAD OF THE FRONT IS AGAIN A POSSIBILITY OVERNIGHT. && .SHORT TERM /SUNDAY/... SUNDAY THE FRONTAL SYSTEM TO OUR WEST AND THE RIDGE OVER THE ATLANTIC WILL SEND A DEEP PLUME OF MOISTURE WITH 2-3 SIGMA ABOVE NORMAL PW INTO OUR REGION. HIGH PW VALUES ARE LIKELY IN THE STRONG FLOW AHEAD OF THE COLD FRONT. WHILE THE STRONGEST FLOW WILL LIKELY LIFT NE OF OUR AREA...THE FLOW WILL BE RATHER STRONG FOR EARLY AUG. CAPE VALUES ARE GOOD FOR SEVERE WEATHER BUT NOT OVERLY IMPRESSIVE. BUT OVER 20KTS OF 1KM SHEAR WITH 1200 TO 1800JKG-1 IMPLIES DEEP UPDRAFTS AND GOOD SHEAR. THIS SHOULD FAVOR THE DEVELOPMENT...MAINLY IN THE AFTERNOON INTO EVENING OF STRONG TO POTENTIAL SEVERE THUNDERSTORMS. FAVORING MORE LINEAR SYSTEMS WITH POTENTIAL BOW DEVELOPMENT. MOST GUIDANCE SHOWS STRONG LOW-LEVEL SHEAR WHICH WILL REQUIRE MONITORING. MULTI-CELLULAR DAY LIKELY WITH BOWING SEGMENTS HIGH PROBABILITY THINKING AT THIS TIME. MOISTURE FLUX...OFTEN ALIGNS WELL WITH OUR BETTER SEVERE EVENTS PEAKS 1800 UTC SUNDAY TO ABOUT 0000 UTC MONDAY. GOOD BET STRONG STORMS FROM ABOUT 2 PM SUNDAY UNTIL 8 PM IN EAST. UPPED POPS IN AFTERNOON INTO 80S BUT KEPT CLOSE TO NEIGHBORS FOR COLLABORATION. PROBABLY NEED 90S IN THERE! && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... GEFS/SREF/GFS ALL SLOW TO CLEAR OUT THE RESIDUAL MOISTURE MONDAY MORNING IN SOUTHEAST. BUT WINDS ARE WESTERLY. MAY TAKE UNTIL MID- MORNING MONDAY TO GET THE DRY AIR INTO THE BOUNDARY LAYER. BUT PW FALLS BELOW NORMAL STATE WIDE MONDAY. KEPT POPS LOWER THAN GUIDANCE THROUGH WEDNESDAY AND GOT RID OF SHOWERS AS THE PW VALUES ARE NEAR TO SLIGHTLY BELOW NORMAL. PW IS NEAR NORMAL BY THURSDAY INTO SATURDAY SO KEPT CLOSE TO GUIDANCE. TEMPERATURE-WISE...850 HPA TEMPERATURES MAINLY NEAR NORMAL. SLIGHT SURGE OF CLOSE TO 1 SIGMA ABOVE NORMAL WEDNESDAY AHEAD OF WHAT MODELS IMPLY WOULD BE A SECONDARY COLD FRONT TAKING THE EDGE OF A BIT MORE THURSDAY INTO FRIDAY. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... CONDITIONS HAVE IMPROVED TO HIGH MVFR/LOW VFR AS LAST OF THE HAZE CONTINUES TO THIN OUT. LOCALIZED REDUCED CONDITIONS CAN BE EXPECTED LATER TODAY IN AND AROUND AN THUNDERSTORMS THAT ARE EXPECTED TO DEVELOP THIS AFTERNOON AND EARLY EVENING...FROM ABOUT 22Z THROUGH 03Z TONIGHT. OUTLOOK... .SUN...A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS...ESPECIALLY SUNDAY PM AS A COLD FRONT MOVES THROUGH. .MON...CHC OF A SHOWER OR STORM EARLY...THEN MAINLY VFR. .TUES-WED...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && SYNOPSIS...LA CORTE/CERU/MARTIN NEAR TERM...LA CORTE/CERU/MARTIN SHORT TERM...LAMBERT/MARTIN LONG TERM...GRUMM/MARTIN AVIATION...LA CORTE
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 444 AM EDT SAT AUG 4 2012 PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-051000- WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD- NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN- JUNIATA-SOMERSET-BEDFORD-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING- SULLIVAN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND- ADAMS-YORK-LANCASTER- 444 AM EDT SAT AUG 4 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. STRONG...TO POSSIBLY SEVERE THUNDERSTORMS WILL FORM ALONG AND IN ADVANCE OF A POTENT COLD FRONT LATE SUNDAY AFTERNOON AND EVENING. THE MAIN THREAT WILL BE STRONG TO DAMAGING WINDS...ALONG WITH VERY HEAVY RAIN AND DANGEROUS LIGHTNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED. MARTIN
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1102 AM EDT SAT AUG 04 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0200 PM TSTM WND DMG 2 SE HAMPTON 39.91N 77.04W
08/03/2012 ADAMS PA 911 CALL CENTER
NUMEROUS TREES ACROSS ROAD.
0210 PM TSTM WND DMG 7 WSW SHIPPENSBURG 40.01N 77.64W
08/03/2012 FRANKLIN PA 911 CALL CENTER
LARGE TREE DOWN ALONG CUMBERLAND HIGHWAY.
0210 PM TSTM WND DMG 4 SSW ORRSTOWN 40.00N 77.64W
08/03/2012 FRANKLIN PA PUBLIC
TREE DOWN.
0213 PM HAIL 2 SSE ORRSTOWN 40.03N 77.60W
08/03/2012 E0.88 INCH FRANKLIN PA PUBLIC
0215 PM TSTM WND DMG 3 WNW ABBOTTSTOWN 39.90N 77.03W
08/03/2012 ADAMS PA PUBLIC
WIRES AND BRANCHES DOWN.
0220 PM HAIL YORK 39.96N 76.73W
08/03/2012 M0.50 INCH YORK PA TRAINED SPOTTER
ONE HALF INCH HAIL IN YORK
0305 PM TSTM WND DMG 1 W YORK HAVEN 40.11N 76.73W
08/03/2012 YORK PA PUBLIC
MULTIPLE TREES DOWN.
0320 PM TSTM WND DMG GOLDSBORO 40.15N 76.75W
08/03/2012 YORK PA TRAINED SPOTTER
NUMEROUS LARGE TREES AND POWER LINES DOWN
0320 PM TSTM WND GST GOLDSBORO 40.15N 76.75W
08/03/2012 M82 MPH YORK PA TRAINED SPOTTER
MEASURED WIND GUST IN GOLDSBORO
0320 PM HAIL VALLEY GREEN 40.16N 76.79W
08/03/2012 E0.88 INCH YORK PA PUBLIC
0325 PM HAIL 2 E VALLEY GREEN 40.16N 76.76W
08/03/2012 M1.00 INCH YORK PA TRAINED SPOTTER
QUARTER SIZE HAIL IN ETTERS... PA
0445 PM HAIL JOHNSTOWN 40.33N 78.92W
08/03/2012 M0.50 INCH CAMBRIA PA TRAINED SPOTTER
ONE HALF INCH HAIL IN JOHNSTOWN
&&
EVENT NUMBER CTP1200353 CTP1200352 CTP1200359 CTP1200360 CTP1200361
CTP1200358 CTP1200362 CTP1200355 CTP1200356 CTP1200363 CTP1200354
CTP1200357
COLBERTThe Sterling radar (KLWX), 128 km away, was scanning. The volume nearest the first event began at 16:43 UTC.
4 thunderstorm wind, 1 hail, 1 flash flood. Local standard time, as filed.
Thunderstorm winds measured around 70 mph knocked down several large limbs in Wellsville.
Thunderstorm winds estimated near 60 mph knocked down several trees and utility wires in Wertzville.
Thunderstorm winds estimated near 60 mph knocked down numerous trees and utility wires in and around the city of York.
Torrential thunderstorm downpours produced an inch of rainfall in 20 minutes in York. This resulted in significant urban flooding with numerous flooded streets.
Thunderstorm winds estimated near 60 mph flattened the Turbotville Train Station. Several large branches were also down along SR 44 between McEwensville and Turbotville. This report was relayed by the Turbotville Borough Heritage Society who had been overseeing the Turbotville Train Station Relocation Project for approximately 2.5 years.
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, August 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: 390998, 390949, 390951, 390958, 391162, 390980.