Narrow lines of low-topped convection were able to tap into strong winds just off the surface to produce wind damage across central Pennsylvania during the late afternoon and evening of November 15, 2020.
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.
Narrow lines of low-topped convection were able to tap into strong winds just off the surface to produce wind damage across central Pennsylvania during the late afternoon and evening of November 15, 2020.
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 Nov 15, 2:50 PM EST, 25 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 250 PM EST Sun Nov 15 2020 .SYNOPSIS... Windswept rain showers will continue today with an increasing potential for strong to locally damaging winds associated with a sharp cold frontal passage. A stretch of gusty winds will continue through early week with temperatures trending below average. Lake effect snow accumulation remains probable in the northwest PA snowbelts and parts of the western Alleghenies Monday night through Tuesday. The early to midweek cool down will be short-lived as temperatures rebound quickly and trend warmer to above average by the end of next week. && .NEAR TERM /THROUGH TONIGHT/... Risk happens slowly, then all at once. Low-topped squall line heading for NW PA has produced numerous measured severe wind gusts of 60-75+ mph across northern/central OH over the past couple of hours. Current expectations are for this line to continue moving rapidly east-northeastward across northeastern OH into northwestern PA through the rest of the afternoon. Severe Thunderstorm Watch #510 has been issued for the NW Alleghenies through 600 PM EST. We are monitoring the potential for another low-topped SQ line capable of producing strong to locally damaging winds this evening across the eastern 1/2 of the CWA. There may be a bit more instability available into southeast PA, but the best kinematic forcing is over NW PA. Forecast soundings and upstream obs suggest advisory level gusts are likely to occur on a larger scale behind sharp cold frontal passage, owing to steep lapse rates and strong post- frontal pressure rises. We expanded the wind advisory east of the Alleghenies and pushed out the endtime to 03 UTC Mon. Key takeaway: windswept rain through this evening with max gusts up to 50 mph (locally higher within low-topped squall line). Temperatures will head lower tonight but gusty winds should keep minT above guidance. Rain/snow showers are possible across the far NW snowbelt late tonight into early Monday. Unfavorable /SWLY/ low level trajectories and marginal sfc temps should limit snow accumulation. && .SHORT TERM /MONDAY/... Brisk and colder on Monday with gusty west winds 30+mph. Max temps (mid 30s to around 50F) will be near to several degrees below average with the largest departures from normal across the NW Alleghenies. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... An upper-level trough with a few embedded short-waves will swing through the northeast CONUS. A northwest flow of seasonably chilly air should support a period of lake effect snow showers across the northwest mountains/Laurel Highlands Tuesday into Tuesday night. A deep well-mixed layer and cloud temps in the -12 to -18C range through a several kft depth of the upper cloud layer will support good dendritic growth and decent snowfall rates of 1/2 to 1 inch per hour in the expected multiple snowbands. NBM guidance seemed too low with lake effect potential Tuesday and Tuesday night so leaned more toward the superblend with the Sunday morning update. A few inches of accumulation are possible over the northwest zones with 1 to 2 inches over the Laurels. A coating to an inch will be possible elsewhere over the Allegheny Plateau. Areas farther south and east may see flurries, but no accumulation is expected due to ground temperatures just above freezing. A few flurries may linger over the northwest Wednesday, otherwise looking at a dry and chilly day. Latest ECENS and GEFS support fair and progressively milder weather the second half of the week, as upper trough lifts out and ridging builds over the eastern CONUS. Ensemble plumes indicate well above normal temperatures are likely by late in the week, as surface high slips off the Mid Atlantic coast and southwesterly return flow develops. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... Windswept rain showers will move quickly across the airspace this afternoon and evening, and may be accompanied by locally strong sfc wind gusts 40+kt. Flight cats will be variable with brief vis restrictions in heavier downpours and fluctuations in cigs from VFR to IFR. A sharp cold front will sweep through the airspace with winds shifting to 240-270 degrees and post- frontal gusts of 40+kt still possible through the evening. A gusty westerly flow will maintain low cigs across the wrn 1/3 of the airspace into Monday. Conditions will trend VFR to the east of the Alleghenies. Outlook... Mon...MVFR cigs wrn 1/3. Gusty winds 25-30kt from 270 degrees subsiding late. Tue...MVFR cigs and IFR vis psbl over the wrn highlands in scattered snow showers. Gusty winds 25-30kts from 280-310 degrees. Wed...Low cigs psbl early wrn 1/3. Bcmg VFR with winds subsiding. Thu...VFR/no sig wx. Gusty winds psbl from 240 degrees. Fri...VFR/no sig wx. && .CTP WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 10 PM EST this evening for PAZ004>006- 010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066. && SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Lambert/Gutierrez LONG TERM...Fitzgerald/Travis AVIATION...Steinbugl
Hazardous Weather Outlook National Weather Service State College PA 208 PM EST Sun Nov 15 2020 PAZ012-018-019-025>028-034>036-041-042-045-046-049>053-056>059- 063>066-161915- Northern Clinton-Northern Centre-Southern Centre-Blair-Huntingdon- Mifflin-Juniata-Bedford-Fulton-Franklin-Northern Lycoming-Sullivan- Southern Clinton-Southern Lycoming-Union-Snyder-Montour- Northumberland-Columbia-Perry-Dauphin-Schuylkill-Lebanon-Cumberland- Adams-York-Lancaster- 208 PM EST Sun Nov 15 2020 ...WIND ADVISORY IN EFFECT UNTIL 10 PM EST THIS EVENING... This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...This afternoon and tonight. Please listen to NOAA Weather Radio or go to weather.gov/StateCollege on the internet for more information about the following hazards. Wind Advisory. Locally strong to damaging winds are possible within heavy showers and thunderstorms this afternoon and early evening. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Gusty west to northwest winds of 30 to 40 are possible on Tuesday. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ024-033-037-161915- Cambria-Somerset-Tioga- 208 PM EST Sun Nov 15 2020 ...WIND ADVISORY IN EFFECT UNTIL 10 PM EST THIS EVENING... This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...This afternoon and tonight. Please listen to NOAA Weather Radio or go to weather.gov/StateCollege on the internet for more information about the following hazards. Wind Advisory. Locally strong to damaging winds are possible within heavy showers and thunderstorms this afternoon and early evening. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Lake effect snow accumulation is probable late Monday night through early Wednesday. The combination of accumulating snow and gusty winds may result in travel disruptions. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ004>006-010-011-017-161915- Warren-McKean-Potter-Elk-Cameron-Clearfield- 208 PM EST Sun Nov 15 2020 ...WIND ADVISORY IN EFFECT UNTIL 10 PM EST THIS EVENING... ...SEVERE THUNDERSTORM WATCH 510 IN EFFECT UNTIL 6 PM EST THIS EVENING... This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...This afternoon and tonight. Please listen to NOAA Weather Radio or go to weather.gov/StateCollege on the internet for more information about the following hazards. Wind Advisory. Severe Thunderstorm Watch. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Lake effect snow accumulation is probable late Monday night through early Wednesday. The combination of accumulating snow and gusty winds may result in travel disruptions. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. MRS
The Pittsburgh radar (KPBZ), 146 km away, was scanning. The volume nearest the first event began at 20:16 UTC.
20 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm producing winds estimated near 60 mph blew a roof off of a garage near Grand Valley.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees between Garland and Grand Valley.
A severe thunderstorm producing winds estimated near 60 mph knocked down wires near the intersection of Route 958 and Bull Hill Road in Wrightsville.
A severe thunderstorm producing winds estimated near 60 mph knocked down a tree onto a car in the 400 block of Old Pittsfield Road near Youngsville.
A severe thunderstorm producing winds estimated near 60 mph knocked down multiple trees in the vicinity of Sugar Grove.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees along Chestnut Grove Highway (Route 219) north of Grampian.
A severe thunderstorm producing winds estimated near 60 mph blew portions of a metal building onto wires in Kane.
A severe thunderstorm producing winds estimated near 60 mph knocked down several trees an wires in and around Hollsopple in Conemaugh Township.
A severe thunderstorm producing winds estimated near 60 mph produced multiple reports of trees down between Hyde and Winburne.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires in several locations near Somerset, including on the 900 block of New Centerville Road.
A severe thunderstorm producing winds estimated near 60 mph knocked down wires at Sarah Furnace Road and Tennessee Lane in Imler.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires in several locations across northern Bedford County.
A severe thunderstorm producing winds estimated near 60 mph blew the roof off of a mobile home on Neil Road near Shippensburg.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees along Mount Sera Road and West Yellowbreeches Road southwest of Carlisle.
A severe thunderstorm producing winds estimated near 60 mph knocked down wires at the intersection of York Haven Road and Cly Road.
A severe thunderstorm producing winds estimated near 60 mph produced multiple reports of downed trees and wires across southern Lebanon and northern Lancaster counties.
A severe thunderstorm producing winds estimated near 60 mph knocked down several trees in the 7800 block of Fishel Creek Road to the east of Seven Valleys.
A severe thunderstorm producing winds estimated near 60 mph knocked down wires on Summit Drive near Fairview Drive in York.
A severe thunderstorm producing winds estimated near 60 mph produced multiple reports of downed trees and wires on the north and west side of the city of Lancaster.
A severe thunderstorm producing winds estimated near 60 mph knocked down wires onto Mount Airy Road in Shrewsbury.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2020Every state in 2020This day in weather historyWarnings in Pennsylvania, November 2020
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: 927202, 927204, 927210, 927211, 927212, 927213, 927214, 927240, 927216, 927241, 927242, 927243, 927246, 927247, 927248, 927311, 927313, 927314, 927316, 927320.