Thunderstorm clusters formed along a stalled east-west oriented surface boundary and produced isolated damaging winds and hail.
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.
Thunderstorm clusters formed along a stalled east-west oriented surface boundary and produced isolated damaging winds and hail.
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 Jul 22, 2:47 PM EST, 16 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 347 PM EDT FRI JUL 22 2011 .SYNOPSIS... A SUBTROPICAL RIDGE OF HIGH PRESSURE COVERING MUCH OF THE LOWER 48 WILL KEEP THE TEMPERATURES WELL ABOVE NORMAL THIS WEEKEND. TEMPERATURES WILL SLOWLY DECREASE TO NEAR NORMALS THROUGH THE NEXT FEW DAYS AS AN UPPER LEVEL TROUGH DIPS DOWN OVER THE NORTHEASTERN UNITED STATES. THE HEAT WILL BUILD AGAIN DURING THE MIDDLE OF THE WEEK AS THE HIGH PRESSURE RETURNS FROM THE WEST. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... THIS IS ABOUT AS HOT AS IT GETS IN CENTRAL PA THIS AFTERNOON. HEAT INDEX VALUES RAISED A TAD IN SE ZONES WITH 115 DEGREE HI VALUES POSSIBLE IN HARRISBURG...YORK AND LANCASTER. DRIER DPS SEEN IN CENTRAL PA WHERE STATE COLLEGE...CLEARFIELD AND ALTOON HAVE DROPPED INTO THE UPPER 50S TO MID 60S. THIS HAS ALLOWED THE TEMPERATURES TO RISE A COUPLE DEGREES MORE THEN FORECAST /THOUGH HEAT INDEX VALUES HAVE SLACKED SLIGHTLY/. STATE COLLEGE WILL LIKELY FLIRT WITH ITS ALL TIME HIGH OF 102 DEGREES THIS AFTEROON. RADAR SHOWING INCREASING CELLS ACROSS PA/MD BORDER AND SOME OF THESE STORMS LOOK QUITE STRONG WITH GUSTY WINDS AND HEAVY DOWNPOURS. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SATURDAY/... REMANT CONVECTION TO THE WEST WILL APPROACH WESTERN CWA THIS EVENING AND OVERNIGHT. WILL HAVE SLIGHT CHANCE POPS BUT BIGGEST IMPACT WILL BE TO KEEP TEMPERATURES VERY WARM OVERNIGHT. THERMAL RIDGE SHOULD SLIDE EAST OF CWA ON SATURDAY PROVIDING SOME RELIEF BUT STILL A VERY HOT SUMMER DAY ONCE AGAIN. SMALL CHANCE STORMS WILL CONTINUE IN THE FORECAST AS WELL. WITH HIGH PWATS OF 2+ STD ABOVE AVERAGE ANY OF THESE CELLS WILL PUT DOWN SOME HEAVY RAIN. WILL KEEP HEAT ADVISORIES/WARNINGS IN PLACE. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... AN UPPER LEVEL TROUGH BRIEFLY AMPLIFIES SWD FROM SE CANADA INTO THE MID ATLC STATES...BRINGING A BREAK IN THE HIGH HEAT. SOMEWHAT COOLER AND NOTICEABLY LESS HUMID AIR SLIDES IN FOR MON/TUE AS TEMPS SLIP BACK CLOSE TO NORMAL. FRONTAL BOUNDARY MAY STAY JUST OFF TO THE SOUTH ON MONDAY...BUT WILL BRING CHANCE FOR SCT TSTMS SAT/SUN/MON...BUT WILL PROVIDE ONLY LIMITED RELIEF TO ONGOING DRY CONDITIONS. WARM FRONT RETURNS FROM THE OHIO VALLEY IN WAKE OF TROUGH LIFTING TO THE NE BY MIDWEEK...SO THE RELIEF FROM THE HEAT/HUMIDITY MAY ONLY BE TEMPORARY. ANOTHER SURGE OF HIGH HEAT IS FORECAST BEHIND THAT FRONT FOR LATE NEXT WEEK INTO THE WEEKEND. AT THE LEAST...TEMPS WILL RETURN TO NOTICEABLY ABOVE NORMAL LEVELS. PRECIP CHANCES REMAIN LOW THROUGH THE END OF THE MONTH. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... HIGH PRESSURE WILL MAINTAIN THE TRANQUIL WEATHER AND LIGHT WINDS. VFR CONDS SHOULD PREVAIL ACROSS MOST OF THE AREA. HOWEVER...HAZE COULD HOLD VSBYS BTWN 5-9SM ACROSS THE REGION. ISOLATED MVFR/IFR CONDITIONS ARE POSSIBLE ACROSS THE S TIER... AS SPOTTY SHRA/TSRA MOVE ACROSS THE AREA. BRIEF MVFR CONDITIONS ARE ALSO POSSIBLE IN THE EARLY SATURDAY MORNING HOURS ACROSS THE REGION AS HAZY CONDITIONS PERSIST. OUTLOOK... SAT-SUN...SCT PM TSRA IMPACTS POSSIBLE. MON...PM TSRA IMPACTS POSSIBLE. TUE...NO SIG WX EXPECTED. && .CLIMATE... RECORD HIGHS AT HARRISBURG /MDT/ AND WILLIAMSPORT /IPT/ FOR JULY 22-23... ..MDT.. 101 7/22 1926 101 7/23 1999 ..IPT.. 100 7/22 1926 99 7/23 1955 THE PROLONGED STRETCH OF HOT TEMPERATURES ABOVE 90F COULD RANK IN THE TOP 5 ALL-TIME FOR CONSECUTIVE DAYS >90F AT BOTH SITES. && .CTP WATCHES/WARNINGS/ADVISORIES... EXCESSIVE HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR PAZ027- 028-036-045-046-049>053-056>059-063>066. HEAT ADVISORY FROM NOON TO 8 PM EDT SATURDAY FOR PAZ019- 025>028-034>036-045-046-049>053-056>059-063>066. HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ012-018-019- 025-026-034-035-041-042. && SYNOPSIS...ROSS NEAR TERM...ROSS SHORT TERM...ROSS LONG TERM...DANGELO/RXR AVIATION...GARTNER/COLBERT CLIMATE...
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 409 AM EDT FRI JUL 22 2011 PAZ012-018-041-042-230815- NORTHERN CLINTON-NORTHERN CENTRE-NORTHERN LYCOMING-SULLIVAN- 409 AM EDT FRI JUL 22 2011 ...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. HEAT ADVISORY. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ004>006-010-011-017-024-033-037-230815- WARREN-MCKEAN-POTTER-ELK-CAMERON-CLEARFIELD-CAMBRIA-SOMERSET-TIOGA- 409 AM EDT FRI JUL 22 2011 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...SATURDAY THROUGH THURSDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ027-028-036-045-046-049>053-056>059-063>066-230815- MIFFLIN-JUNIATA-FRANKLIN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION- SNYDER-MONTOUR-NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL- LEBANON-CUMBERLAND-ADAMS-YORK-LANCASTER- 409 AM EDT FRI JUL 22 2011 ...EXCESSIVE HEAT WARNING IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS EVENING... ...HEAT ADVISORY IN EFFECT FROM NOON TO 8 PM EDT SATURDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. EXCESSIVE HEAT WARNING. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. HEAT ADVISORY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ019-025-026-034-035-230815- SOUTHERN CENTRE-BLAIR-HUNTINGDON-BEDFORD-FULTON- 409 AM EDT FRI JUL 22 2011 ...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS EVENING... ...HEAT ADVISORY IN EFFECT FROM NOON TO 8 PM EDT SATURDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. HEAT ADVISORY. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. HEAT ADVISORY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
248 PM EDT FRI JUL 22 2011
PAZ036-064-221945-
ADAMS PA-FRANKLIN PA-
248 PM EDT FRI JUL 22 2011
...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHERN FRANKLIN AND
WEST CENTRAL ADAMS COUNTIES...
AT 244 PM EDT...A LINE OF STRONG THUNDERSTORMS WAS LOCATED FROM MONT
ALTO TO CLAYLICK TO LINEBURG...MOVING NORTHEAST AT 10 MPH.
EXPECT INTENSE LIGHTNING FROM THESE STORMS. DO NOT STAY IN THE OPEN
NOR SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS
WHEN A THUNDERSTORM APPROACHES. VERY HEAVY RAIN WILL FALL FROM THESE
STORMS...AND WILL CAUSE WATER TO POND ON ROADS AND FILL POOR DRAINAGE
AREAS. THE RAIN WILL CAUSE RAPID RISES ON SMALL STREAMS AND CREEKS.
THESE STORMS WILL BE NEAR MONT ALTO AROUND 310 PM...MARION AROUND 330
PM AND CASHTOWN AROUND 350 PM.
THIS WILL IMPACT I-81 BETWEEN MILE MARKERS 1 AND 15.
THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 11...ROUTE
30.
LAT...LON 3977 7806 3992 7769 3994 7714 3971 7750
3972 7809
FORECASTER: CR/ECSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
338 PM EDT FRI JUL 22 2011
PAZ065-066-222015-
LANCASTER PA-YORK PA-
338 PM EDT FRI JUL 22 2011
...A STRONG THUNDERSTORM WILL AFFECT SOUTH CENTRAL LANCASTER AND
SOUTHEASTERN YORK COUNTIES...
AT 332 PM EDT...A STRONG THUNDERSTORM WAS NEAR GLEN ROCK...MOVING
SOUTHEAST AT 20 MPH.
WIND GUSTS TO 50 MPH AND PENNY SIZE HAIL ARE POSSIBLE WITH THIS
STORM. THIS STORM WILL BE NEAR STEWARTSTOWN AROUND 350 PM...BROGUE
AROUND 400 PM...SHENKS FERRY AROUND 410 PM AND FAWN GROVE AROUND 420
PM.
LAT...LON 3978 7687 3998 7669 3990 7623 3971 7635
3972 7673
FORECASTER: KFThe Sterling radar (KLWX), 111 km away, was scanning. The volume nearest the first event began at 20:01 UTC.
3 thunderstorm wind, 2 hail. Local standard time, as filed.
Thunderstorm winds estimated near 60 mph knocked down trees and utility wires in Paradise Township near Maple Grove.
Thunderstorm winds estimated near 60 mph knocked down trees and utility wires at the intersection of South Lake Road and Old Hanover Road.
Dime to nickel-size hail (up to 0.88 inch diameter) reported on the south-side of York City.
Thunderstorm winds estimated near 60 mph knocked down trees at East Prospect Road and Frysville Road in Windsor Township near Locust Grove.
Dime to penny-size hail (up to 0.75 inch diameter) reported in Hallam.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2011Every state in 2011This day in weather historyWarnings in Pennsylvania, July 2011
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: 315408, 315411, 315414, 315418, 315416.