A quick-moving system tracked from the Ohio Valley eastward across southern Pennsylvania from March 6 into the morning of March 7. Strong warm advection and frontogenesis associated with this system helped to produce a narrow swath of 6 to 10 inches of snow across the northern mountains of Pennsylvania.
Every event with a place to put it; 7 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.
A quick-moving system tracked from the Ohio Valley eastward across southern Pennsylvania from March 6 into the morning of March 7. Strong warm advection and frontogenesis associated with this system helped to produce a narrow swath of 6 to 10 inches of snow across the northern mountains of Pennsylvania. Amounts decreased rapidly on either side of this narrow swath of heavier snow.
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 Mar 6, 2:11 PM EST, 4 hours 49 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 211 PM EST Mon Mar 6 2023 .SYNOPSIS... A strong but fast-moving low pressure area will zip directly over the Laurel Highlands tonight as it speeds eastward. This will lead to a heavy snowfall for the northern mountains this evening and early tonight, and mainly rain for the southern half of the state. High pressure builds in with a gusty wind Tuesday. Expect generally fair weather into Friday with the next mixed precipitation event slated to arrive Friday or Friday night. It will turn blustery and colder for the weekend. && .NEAR TERM /THROUGH TONIGHT/... Radar returns over the north are well aloft, and temps are warming nicely in the srn half where the sun has been out all day. The elongated sfc high is sliding eastward and the easterly wind is picking up in the wrn mtns. The sfc low which will make noise tonight is over central IL with the warm front into nrn OH where some convective clouds (perhaps altocu) have begun to pop up and slide NE quickly. This is where the initial shot of warm advection this evening will be from - moving across OH and wrn PA, developing a band or two of ever-increasing moisture and eventually precip. Temps should be warm enough at onset that the precip over wrn PA will be rain, but wet bulb temps at the sfc over the nrn mtns are around 30F. Thus, we'll have some quick cooling as the atmos moistens up below the developing band(s) of precip, and turn to snow rather quickly - aided by nightfall and normal temp fall. Inflow continues to look like it will be a 40-45KT LLJet and excellent isentropic lift ensues N of the warm front. QPF has be creeping up over the last few mdl runs and current man-machine avgs are 0.5-0.8" along a stripe from Warren to Sullivan counties. There is still some (lessening) uncertainty where the heaviest precip/band(s) set(s) up. Temps are also rather solid wrt previous forecasts. However, the QPF consensus of higher numbers is certainly better than prev. The timing of the event remains the same. It is a quick hitter which is a reason to think that the amounts can't be all that high due to the brief residence time of the best lift/moisture. Looking at the SLRs, the higher numbers are over the NErn third, but are only 12-13:1 in NErn Tioga Co. The SLRs along the axis of best QPF are about 9:1 and drop off very quickly to the south of there. Dry air being advected in from the N is a point toward a very sharp northern edge to the precip. Thus, the gradient along the NY border and into nrn Tioga Co may allow the snow numbers to drop off in a very short distance. However, an expected pivot to the orientation of the best possible band position keeps some uncertainty in the mind of the forecasters. There will be an upgrade from advy to warning for a few of the nrn counties, trying to narrow in on the counties where most of the county is covered by 6+" in the storm total graphics. Still, most of this falls in just 8hrs, meaning we could have quite a few hours of 1"/hr rates over the nrn mtns. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... A few lingering snow showers/flurries across the northern and western highlands Tuesday morning should give way to clearing skies as strong subsidence overspreads the area behind the departing shortwave. A fairly tight pressure gradient should result in gusty northwest winds by Tuesday afternoon, and Bufkit soundings support gusts of 30+ kts. Temperatures will be just a bit below climatological normals, with highs ranging from the mid 30s across the nrn mtns to the upper 40s in the Lower Susq Valley. Additionally, we continue to undercut the NBM dewpoints on Tuesday, as the northwesterly flow and very dry air above a weak inversion signal a potential afternoon dewpoint drop. Continued cold air advection and northerly flow could support a few lake-effect snow showers/flurries sneaking back into the nrn mtns Tues evening into Tues night. However, progged inversion heights are quite low, so any accumulations should be minimal. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Fair weather is expected for Wednesday into Thursday, as an upper level ridge builds eastward into the area. Wednesday will be a bit chillier than normal, with temperatures moderating to near normal by Thursday afternoon. For the end of the week, the focus will shift to a sharpening upper level trough that is expected to dig from the Great Lakes into the northern Mid Atlantic region and evolve into a cutoff low. The associated surface low is progged to track to the west of PA Friday into Fri night, drawing milder air overtop the chilly air in place at the surface, before a secondary low develops off the northern Mid Atlantic Coast. This points towards a potential wintry mix late Friday or Friday night. Odds favor chilly and unsettled conditions into next weekend (especially Saturday), with scattered rain/snow showers as the upper low slowly migrates eastward and off the East Coast. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... Low pressure will pass just S of KJST tonight, sliding along a warm front stretched from KPIT-KLWX. As the N-S ridge of high pressure over the eastern terminals slides eastward over the next couple of hours, the wind will go easterly briefly, then back to the NE and N there. The E wind over the western highlands will back to the north and increase as the low center nears. Precipitation will break out around 22Z over KBFD, and then spread across most of the area N of I-80 before 02Z. The temperatures at first will mean rain for a minute at BFD, but quickly turn to snow. A long-lived band of (mainly) snow will cut thru the nrn mtns for 6-8hrs thru about 06Z. LIFR is expected at BFD and perhaps IPT later this evening and early tonight as the precip gets heavier there. UNV will be on the very srn fringe of the SN early tonight, and may stay all rain (with SN on the ridges) until after 04-05Z. Then, a brief pd of IFR/LIFR is possible there. JST may be all rain for much of the night, but eventually gets cold enough for all snow by the end of the night. AOO/MDT and LNS will miss out on the bulk of the precip, getting some around or just after midnight, but not dipping to IFC for more than an hour or two, and that would be due mainly to low cloud and not the precip. An hr or two of SN is poss at MDT and LNS, but only very late tonight. It should all be over with before sunrise, and probably around 08Z in UNV/AOO/IPT. The low pressure goes east fast, and the falling pressure and incoming high pressure will result in gusty WNW wind on Tuesday. Some upslope SHSN are expected for the wrn highlands as a small secondary wave drops across in the morning. Outlook... Wed...AM low cigs possible NW Mtns. VFR elsewhere. Thu...VFR conditions. Fri...IFR poss areawide in snow/mixed precip. Sat...IFR/MVFR W in SHSN. MVFR/VFR elsewhere. Gusty wind. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 2 AM EST Tuesday for PAZ004>006- 010-011. Winter Weather Advisory from 6 PM this evening to 5 AM EST Tuesday for PAZ012-017>019-037-041-042-045-046. Winter Weather Advisory from 7 PM this evening to 5 AM EST Tuesday for PAZ049-051>053-058. && SYNOPSIS...Dangelo NEAR TERM...Dangelo SHORT TERM...Evanego LONG TERM...Fitzgerald/Evanego AVIATION...Dangelo
Hazardous Weather Outlook National Weather Service State College PA 248 PM EST Mon Mar 6 2023 PAZ005-006-011-012-041-042-072000- McKean-Potter-Cameron-Northern Clinton-Northern Lycoming-Sullivan- 248 PM EST Mon Mar 6 2023 ...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 5 AM EST TUESDAY... 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. Winter Storm Warning. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ024>028-033>036-050-056-057-059-063>066-072000- Cambria-Blair-Huntingdon-Mifflin-Juniata-Somerset-Bedford-Fulton- Franklin-Snyder-Perry-Dauphin-Lebanon-Cumberland-Adams-York- Lancaster- 248 PM EST Mon Mar 6 2023 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...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ017>019-037-045-046-072000- Clearfield-Northern Centre-Southern Centre-Tioga-Southern Clinton- Southern Lycoming- 248 PM EST Mon Mar 6 2023 ...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO 5 AM EST TUESDAY... 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. Winter Weather Advisory. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ004-010-072000- Warren-Elk- 248 PM EST Mon Mar 6 2023 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 2 AM EST TUESDAY... 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. Winter Weather Advisory. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ049-051>053-058-072000- Union-Montour-Northumberland-Columbia-Schuylkill- 248 PM EST Mon Mar 6 2023 ...WINTER WEATHER ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO 5 AM EST TUESDAY... 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. Winter Weather Advisory. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather.
The national radar mosaic for the moment the first event began.
6 winter storm, 1 winter weather. Local standard time, as filed.
A quick-hitting winter storm produced a 7 to 10 inches of snow across McKean County in less than 12 hours. US Route 6 was closed between Smethport and Port Allegheny for over an hour due to wintry conditions.
A quick-hitting winter storm produced a 8 to 10 inches of snow across all but far northern Potter County in less than 12 hours.
A quick-hitting winter storm produced a 6 to 9 inches of snow across Cameron County in less than 12 hours.
A quick-hitting winter storm produced a 7 to 10 inches of snow across northern Clinton County in less than 12 hours.
A quick-hitting winter storm produced a 7 to 10 inches of snow across northern Lycoming County in less than 12 hours. US Route 15 was closed in both directions for nearly 3 hours between Route 184 and Route 284 (Buttonwood) in Cogan House Township due to multiple tractor trailers being stuck in the snow.
A quick-hitting winter storm produced a 6 to 8 inches of snow across all but far northern Sullivan County in less than 12 hours.
A few inches of snow led to slick conditions on US Route 15 in Tioga County, causing a tractor trailer to jack-knife and closing the northbound lanes in Liberty Township for nearly an hour and a half.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2023Every state in 2023This day in weather historyWarnings in Pennsylvania, March 2023
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: 1074311, 1074312, 1074313, 1074314, 1074315, 1074316, 1074317.