A quick-moving area of low pressure passed south of Pennsylvania during the evening of Saturday, February 17 and brought a quick period of moderate to heavy snow across south-central Pennsylvania. Snowfall rates of 1-2+ per hour were reported.
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 area of low pressure passed south of Pennsylvania during the evening of Saturday, February 17 and brought a quick period of moderate to heavy snow across south-central Pennsylvania. Snowfall rates of 1-2+ per hour were reported.
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 Feb 17, 1:52 PM EST, 8 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 152 PM EST Sat Feb 17 2018 .SYNOPSIS... Low pressure, located over the southern Mississippi Valley early this morning, will track northeast to the Mid Atlantic coast by this evening. An anomalous upper level ridge will build off the east coast next week, with a dying cold front pushing into the state on Wednesday. Abnormally mild conditions will prevail for much of next week. Temperatures will be more typical of early Spring than mid Winter. && .NEAR TERM /THROUGH TONIGHT/... Mostly clear early morning skies across central and eastern areas will quickly be replaced by mid and high cloud through late morning. Overnight and early morning guidance in line with going thinking for no significant changes this morning. Southern plains shortwave and associated surface low tracks northeast to the southern Virginia by late in the day, then off the Delmarva Peninsula this evening. A several hour period of moderate WAA/lift will bring a period of light ot moderate snow to the forecast area this afternoon and evening. The only area that may see anything other than snow is across far southern Lancaster and York Counties which may mix with or change to rain later this evening. All headlines in good shape for a widespread 2 to 4 inches over southern PA and 1-2 in the north. Portions of Schuylkill, Lebanon and northern York/Lancaster stand to see the higher end, with a localized 5-6" amounts possible. Heaviest snow will coincide with the arrival of jet entrance region between 22Z- 02Z, where HREFV2 indicates a few hours of 1+ inch/hour rates over the lower Susq Valley. Behind increasing and thickening/lowering clouds, highs should reach into the upper 30s across the Susq Valley...but temps will drop quickly to around freezing as snow arrives and not diminish accums significantly. Expect snow to taper off between 00Z-03Z, as low pressure passes off the Delmarva. However, much lighter orographic snow is likely to linger over the Alleghenies until after midnight. && .SHORT TERM /SUNDAY/... High pressure will build over the region on Sunday, supplying fair and mild weather. Model soundings indicate some early stratocu over the Alleghenies. Otherwise mostly sunny skies expected. Mixing down ensemble mean 925mb temps of around 0C translate to expected max temps from the upper 30s over the high terrain of the Alleghenies, to the mid 40s over the Susq Valley. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Made minor changes to the fcst package. Main thing for Sunday night was to lower temperatures...given new guidance and also that some snow will likely result in temperatures falling off quickly after sunset. Took out rain for early Monday morning...except for the far southwest. This area likely to be above freezing. Points further east will see rain later on Monday morning...given time for temperatures to rise above freezing. QPF for Monday and Monday night will be much lighter than the event we had Thursday evening, as the warm front lifts quickly northward. Overall an anomalous upper ridge builds along the east coast next week. Heights rise to 588 across southern PA at 500 mb Tuesday. Much of the area will be well into the 60s Tuesday and Wednesday...but could warm well into the 70s if winds mix down. Slightly cooler later in the week...as a cold front slips southward into the area...as high pressure builds over eastern Canada and New England. Models keep the basic pattern the same...so by next weekend...mild conditions could return. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... Snow into far southwestern PA now. VFR conditions will quickly give way to MVFR and IFR conditions by late afternoon and early evening...as snow moves into our area. Conditions should improve across eastern areas shortly after Midnight...as the storm quickly moves out of the area. Some lower clouds and light snow showers could linger across the central and western areas to just after sunrise on Sunday. Overall...not a bad day for Sunday. Lots of sun by late morning. Winds will die down by late aft. Some showers and lower clouds next week...mainly for a brief time Monday...and later on Wednesday...but much of the time will be dry with VFR conditions. Also on the mild side. Outlook... Mon...Restrictions return with some light rain. Tue-Wed...Restrictions likely in rain showers, mainly NW at times...and late Wed elsewhere. Thu...Clearing north. Still a chance of showers north. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 2 AM EST Sunday for PAZ027-028- 050>053-056>059-063>066. Winter Weather Advisory until 4 AM EST Sunday for PAZ024-033. Winter Weather Advisory until 11 PM EST this evening for PAZ025-026-034>036. && SYNOPSIS...Fitzgerald/Martin NEAR TERM...DeVoir/Fitzgerald SHORT TERM...Fitzgerald LONG TERM...Martin AVIATION...Martin
Hazardous Weather Outlook National Weather Service State College PA 234 AM EST Sat Feb 17 2018 PAZ027-028-050>053-056>059-063>066-180745- Mifflin-Juniata-Snyder-Montour-Northumberland-Columbia-Perry-Dauphin- Schuylkill-Lebanon-Cumberland-Adams-York-Lancaster- 234 AM EST Sat Feb 17 2018 ...WINTER WEATHER ADVISORY IN EFFECT FROM 4 PM THIS AFTERNOON TO 2 AM EST SUNDAY... 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...Sunday through Friday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ004>006-010>012-017>019-037-041-042-045-046-049-180745- Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield- Northern Centre-Southern Centre-Tioga-Northern Lycoming-Sullivan- Southern Clinton-Southern Lycoming-Union- 234 AM EST Sat Feb 17 2018 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. A light snowfall is expected late this afternoon into the evening and will result in slippery roads. .DAYS TWO THROUGH SEVEN...Sunday through Friday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ024-033-180745- Cambria-Somerset- 234 AM EST Sat Feb 17 2018 ...WINTER WEATHER ADVISORY IN EFFECT FROM 2 PM THIS AFTERNOON TO 4 AM EST SUNDAY... 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...Sunday through Friday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ025-026-034>036-180745- Blair-Huntingdon-Bedford-Fulton-Franklin- 234 AM EST Sat Feb 17 2018 ...WINTER WEATHER ADVISORY IN EFFECT FROM 2 PM THIS AFTERNOON TO 11 PM EST 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. Winter Weather Advisory. .DAYS TWO THROUGH SEVEN...Sunday through Friday. 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.
7 winter storm. Local standard time, as filed.
A winter storm produced 6 to 9 inches of snow in a 12 hour period across Schuylkill County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Dauphin County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Lebanon County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Perry County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Cumberland County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Juniata County.
A winter storm produced 6 to 7 inches of snow in a 12 hour period across Somerset County.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2018Every state in 2018This day in weather historyWarnings in Pennsylvania, February 2018
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: 734640, 734641, 734642, 734643, 734644, 734645, 734646.