An ice storm impacted much of central Pennsylvania with anywhere from a trace of ice in the Lower Susquehanna Valley up to a half an inch of ice accumulation in the southern Alleghenies and Laurel Highlands.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. 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.
An ice storm impacted much of central Pennsylvania with anywhere from a trace of ice in the Lower Susquehanna Valley up to a half an inch of ice accumulation in the southern Alleghenies and Laurel Highlands.
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 Jan 1, 7:05 AM EST, 6 hours 25 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 705 AM EST Fri Jan 1 2021 .SYNOPSIS... Low pressure will track west of Pennsylvania late today and tonight. Another southern stream low pressure system will lift up the east coast late in the weekend. High pressure ridging is likely over the area early next week. && .NEAR TERM /THROUGH TONIGHT/... Short term guidance continues to indicate a light to moderate icing event over most of the forecast area later today, as warm advection arrives in advance of low pressure lifting into the Ohio Valley and high pressure over New England maintains cold air at low levels. Model soundings indicate there could be a brief period of snow or sleet at the onset of precipitation, but any accumulation should be very minor and limited to the northern counties. Latest guidance indicates precipitation will arrive over the southwest part of the forecast area very late this morning and reach the northeast counties by late afternoon. As is typical here in Central Pa, ice accretion will be highly elevation dependent due to surface temperatures within a couple of degrees from 32F. Model qpf supports ice accretion of greater than a quarter inch on the the ridgetops of central Pa, especially above 2000ft, while little if any icing appears likely in the lowest elevations of the Susquehanna Valley. Have upgraded the advisory to an Ice Storm Warning over Somerset County, where average elevation is the highest in the forecast area and where WPC, NBM and HREF all indicate a decent coverage of greater than a quarter inch of ice. Model soundings indicate freezing rain should taper off to light rain or drizzle over most of the area between 00Z-05Z, as southerly flow draws warmer air into the area and most significant precipitation associated with low level jet shifts east of the area. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... A few orographic rain showers are possible early Saturday over the northwest mountains. Otherwise, expect dry weather, as large scale subsidence overspreads the region behind departing shortwave. Deepening low pressure along the New England coast will result in a fairly tight gradient and breezy conditions across Pa Saturday. Bukfit soundings indicate there will be gusts in the 25-30kt range around midday, then diminishing winds late, as high pressure approaches from the west. Despite the passage of a trailing cold front early in the day and plenty of post-frontal stratocu, temperatures should be quite a bit above average Saturday. GEFS mean 925mb temps around 2C support highs from the low 40s over the northwest mountains, to the low 50s in the southeast. Fair weather is expected Saturday night, as surface high passes over the state. Focus then shifts to southern southern stream shortwave lifting out of the Mississippi Valley. Very little cold air to work with, but retreating surface high over New England should provide just enough cold air to support a light wintry mix across much of the forecast area as warm advection arrives Sunday. A lack of model spread, combined with latest NBM 50th percentiles, suggest a 1-2 inch snowfall across northern Pa and a light ice accumulation over the south are the most likely outcomes from this event. Precipitation is likely to taper off Sunday night, as the mid level shortwave edge east of the state. && .LONG TERM /MONDAY THROUGH THURSDAY/... Once Sunday's system moves off the east coast, the pattern should become more benign over the eastern CONUS, with short- wave ridging aloft likely by mid-week. This should translate to mostly dry weather for the Commonwealth, along with seasonable temperatures for early January. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... Storm system moving toward the Great Lakes fr0m the Mississippi valley thios morning. Cirrus clouds ahead of this overspreading the forecast area with a general OVC250 which will lower through the morning hours. The low pressure system will track to the west of the area but low level cold air in place, comfortably happy sitting in the valleys of central PA, will result in frozen precipitation for all locations by early afternoon. With wet bulb temperatures forecast to be in the mid 20s at the start of the precipitation, expect an IP/-FZRA mix which will transition to -FZRA. Ageostrophic winds at 925mb show a northerly component for several hours this afternoon over the southeast airfields of KMDT and KLNS. After which, a southerly component will help transition the precipitation to rain. Elsewhere, ageostrophic winds will keep -FZRA going until after 00Z when most of the low level cold air can be scoured out. After which all areas are subject to LIFR in -DZ and FG as the milder air moves over the melting surface ice. Winds above the deck will be screaming from the southwest so added WS/020 as winds approach 50kts in all locations later this evening. Conditions will improve on Saturday, before deteriorating again Sat night into Sunday as another storm system brings light rain and snow to central PA. Outlook... Sat...Restrictions early with lingering low cigs. Gradual improvement by aftn. Sat night-Sun...Deteriorating conds, with light rain/snow developing. Mon and Tue...Lingering restrictions in -SHSN across northern and western highlands. Becoming VFR elsewhere. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 10 AM this morning to 1 AM EST Saturday for PAZ004>006-010>012-017>019-024>028-034>037-041- 042-045-046-049>053-056>058-063-064. Ice Storm Warning until midnight EST tonight for PAZ033. && SYNOPSIS...Fitzgerald NEAR TERM...Fitzgerald SHORT TERM...Fitzgerald LONG TERM...Jurewicz/Martin AVIATION...Evanego/Tyburski
Hazardous Weather Outlook National Weather Service State College PA 719 AM EST Fri Jan 1 2021 PAZ033-021230- Somerset- 719 AM EST Fri Jan 1 2021 ...ICE STORM WARNING IN EFFECT UNTIL MIDNIGHT EST TONIGHT... 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. Ice Storm Warning. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. A light wintry mix could result in icy roads Sunday, mainly during the morning hours. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ004-005-010-011-017>019-024>028-034>036-050-056>058-063-064- 021230- Warren-McKean-Elk-Cameron-Clearfield-Northern Centre-Southern Centre- Cambria-Blair-Huntingdon-Mifflin-Juniata-Bedford-Fulton-Franklin- Snyder-Perry-Dauphin-Schuylkill-Cumberland-Adams- 719 AM EST Fri Jan 1 2021 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 1 AM EST 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. Winter Weather Advisory. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. A light wintry mix could result in icy roads Sunday, mainly during the morning hours. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ059-065-066-021230- Lebanon-York-Lancaster- 719 AM EST Fri Jan 1 2021 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. A light wintry mix could possibly result in icy roads Sunday, mainly during the morning hours. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ006-012-037-041-042-045-046-049-051>053-021230- Potter-Northern Clinton-Tioga-Northern Lycoming-Sullivan- Southern Clinton-Southern Lycoming-Union-Montour-Northumberland- Columbia- 719 AM EST Fri Jan 1 2021 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 1 AM EST 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. Winter Weather 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.
The national radar mosaic for the moment the first event began.
2 ice storm. Local standard time, as filed.
An ice storm produced over a quarter of an inch (0.25) of ice accumulation in Cambria County. Ice accumulation knocked down a power line onto Scalp Avenue near Hostetler Road in Geistown.
An ice storm produced a half an inch (0.50) of ice accumulation at Seven Springs Ski Resort and a quarter of an inch (0.25) in Somerset Borough.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2021Every state in 2021This day in weather historyWarnings in Pennsylvania, January 2021
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: 927187, 927188.