Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2024
Severe Thunderstorm Warning 183, NWS State College, PA
NWS State College, PA issued this severe thunderstorm warning at Sep 21, 2024, 11:40 PM EDT for Lancaster County, York County, Pennsylvania. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 21, 2024, 11:40 PM EDT (03:40 UTC)
- Expired
- Sep 22, 2024, 12:30 AM EDT
- In force
- 50 min
- Issued by
- NWS State College, PA
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Lancaster County, PA, York County, PA
The radar
The Sterling radar (KLWX), 141 km from the middle of the area, began a volume at 03:41 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Pittsburgh, PA (KPIT), launched 00:00Z, 3.7 hours before the alert went out and 311 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 5 J/kg
- Mixed-layer CIN
- -64 J/kg
- Mixed-layer LCL
- 2217 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 24 m²/s²
- 0-3 km storm-relative helicity
- 82 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Sep 21, 9:59 PM EDT, 1 hour 41 minutes earlier.
Area forecast discussion, Sep 21, 9:59 PM EDT, 1 hour 41 minutes before
Area Forecast Discussion National Weather Service State College PA 959 PM EDT Sat Sep 21 2024 .SYNOPSIS... A frontal system will fall apart as it moves through Central PA overnight accompanied by scattered showers and thunderstorms. Mostly cloudy, but rain- free weather returns for Sunday, before a slow-moving trough brings the next chance of rain from Monday through midweek. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Cluster of thunderstorms from Williamsport west to Elk County is expected to persist and drop south into the early morning hours. At this point, heavy rain/flooding and a sub-severe gusty wind threat are primary concerns with all hands on deck continuing to monitor. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... Forecast soundings indicate an upsloping southeast flow will result in persistent stratus and perhaps a bit of fog or drizzle over the central/east zones for Sun and Sun night. The cloud cover and flow off of the Atlantic should result in markedly cooler afternoon temps Sunday than on Saturday, with highs likely stuck in the 60s over the Central Mtns. Sun night looks mainly dry with prev anticipated forcing holding off a bit longer/later. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... Surging PWATs with enhanced energy from an upper-level trough will bring about an unsettled pattern throughout much of the long-term period. Deterministic model guidance is in fairly good agreement that low-pressure stationed over the southern Great Lakes will bring about shower activity on Monday; however, model guidance has trended slower with the onset of rainfall and have chopped PoPs throughout the early period of the day as models tend to converge on a (slightly) slower progression. The best chances of showers will come across the Laurel Highlands during the late morning hours, continuing eastward throughout the afternoon/evening hours. Elevated instability will be highest across the western third of the area, so have limited mentions of storms to this area during the PM hours. Model guidance outlines another surface low-pressure system tracking northeastward across western portions of the Upper Ohio Valley and into southern Ontario Tuesday into Wednesday, with slightly more moisture and lift available as the warm front aligns itself north-to-south across west-central PA. Given slightly better lift with this low-pressure system coupled with enhanced moisture, have retained likely PoPs in the Tuesday to Wednesday timeframe. Given PWATs in the 1.50-1.75" range on Wednesday, locally heavy rainfall will be possible and this has been outlined with marginal (level 1/4) risks in the D4 (W) and D5 (E) Excessive Rainfall Outlooks from the Weather Prediction Center. Impacts at this time look less likely at this time given ongoing dry conditions across especially SW PA where D2 drought conditions persist; however, any heavier rainfall in the preceding days could allow for slightly more impacts. As we shift into the later part of the week, slightly more model uncertainty with regards to low-pressure moving N/E of the area and how this will impact rainfall chances for Central PA. At this time, have capped PoPs at a chance for Thursday as the low-pressure system will be slightly closer to our eastern half, and capped at a slight chance for Friday, keeping close to NBM model guidance in this timeframe. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Late this evening showers and thunderstorms will continue affect most TAF sites except, most likely, for KAOO/KJST. Overnight, medium to high confidence in IFR/LIFR across central Pennsylvania. GLAMP model guidance and HREF probabilities continue to suggest fog formation, so have trended towards GLAMP guidance this cycle. As sunrise approaches, very slow improvement is expected with the bulk of airfields expected to stay sub-VFR through 18Z Sunday with exceptions at BFD/JST. Outlook... Mon-Thu...Scattered showers, restrictions possible. && .CLIMATE... The high temperature in Bradford on Friday set a new record high of 82 degrees. This broke the record of 81 degrees set in 1978 and 2016. The first day of autumn 2024 (Fall Equinox) begins at 8:44 am EDT on Sunday September 22nd. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && SYNOPSIS...Dangelo NEAR TERM...Dangelo/Gartner SHORT TERM...Dangelo/Gartner LONG TERM...Gartner/NPB AVIATION...Gartner/NPB CLIMATE...Steinbugl/Martin/NPB
Hazardous weather outlook, Sep 21, 2:37 PM EDT, 9 hours 3 minutes before
Hazardous Weather Outlook National Weather Service State College PA 237 PM EDT Sat Sep 21 2024 PAZ004-037-041-042-046-051>053-057>059-066-221845- Warren-Tioga-Northern Lycoming-Sullivan-Southern Lycoming-Montour- Northumberland-Columbia-Dauphin-Schuylkill-Lebanon-Lancaster- 237 PM EDT Sat Sep 21 2024 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...This afternoon and tonight. No hazardous weather is expected at this time. .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. PAZ005-006-010>012-017>019-024>028-033>036-045-049-050-056-063>065- 221845- McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield- Northern Centre-Southern Centre-Cambria-Blair-Huntingdon-Mifflin- Juniata-Somerset-Bedford-Fulton-Franklin-Southern Clinton-Union- Snyder-Perry-Cumberland-Adams-York- 237 PM EDT Sat Sep 21 2024 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...This afternoon and tonight. Showers and thunderstorms may make strong, gusty winds and small hail into the evening hours. .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.
In the hours before
Local storm report, Sep 21, 11:03 PM EDT, 37 minutes before
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</html>Local storm report, Sep 21, 11:10 PM EDT, 30 minutes before
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</html>Special weather statement, Sep 21, 11:21 PM EDT, 19 minutes before
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</html>The office that day
Everything else NWS State College, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 8:00 PM EDT | Severe Thunderstorm Warning | CTP | Cameron, McKean, Potter | 45 min |
| Sep 21, 8:10 PM EDT | Special Weather Statement | CTP | Warren | 35 min |
| Sep 21, 8:40 PM EDT | Severe Thunderstorm Warning | CTP | Clinton, Lycoming, Potter, Tioga | 50 min |
| Sep 21, 8:56 PM EDT | Special Weather Statement | CTP | Clinton | 34 min |
| Sep 21, 8:59 PM EDT | Special Weather Statement | CTP | Cameron | 31 min |
| Sep 21, 9:14 PM EDT | Severe Thunderstorm Warning | CTP | Cameron, Clearfield, Elk | 46 min |
| Sep 21, 9:17 PM EDT | Special Weather Statement | CTP | Cameron | 28 min |
| Sep 21, 9:26 PM EDT | Special Weather Statement | CTP | Clinton | 34 min |
| Sep 21, 9:39 PM EDT | Special Weather Statement | CTP | Elk | 36 min |
| Sep 21, 9:44 PM EDT | Special Weather Statement | CTP | Cameron | 31 min |
| Sep 21, 9:49 PM EDT | Areal Flood Advisory | CTP | Dauphin | 2 hr |
| Sep 21, 9:58 PM EDT | Special Weather Statement | CTP | Clinton | 32 min |
| Sep 21, 10:00 PM EDT | Flash Flood Warning | CTP | Dauphin | 110 min |
| Sep 21, 10:08 PM EDT | Special Weather Statement | CTP | Northumberland | 37 min |
| Sep 21, 10:15 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin | 45 min |
| Sep 21, 10:21 PM EDT | Areal Flood Advisory | CTP | Montour, Northumberland, Union | 2 hr |
| Sep 21, 10:37 PM EDT | Flash Flood Warning | CTP | Dauphin | 113 min |
| Sep 21, 10:44 PM EDT | Flash Flood Warning | CTP | Northumberland, Union | 2 hr |
| Sep 21, 10:52 PM EDT | Areal Flood Advisory | CTP | Dauphin, York | 2 hr |
| Sep 21, 10:53 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin, Lancaster, York | 52 min |
| Sep 21, 10:58 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin, Lebanon, Northumberland, Schuylkill, Snyder | 32 min |
| Sep 21, 11:11 PM EDT | Areal Flood Advisory | CTP | Northumberland, Snyder, Union | 2 hr |
| Sep 21, 11:21 PM EDT | Special Weather Statement | CTP | Lebanon | 24 min |
| Sep 21, 11:28 PM EDT | Special Weather Statement | CTP | Dauphin, Juniata, Lebanon, Perry | 62 min |
| Sep 21, 11:50 PM EDT | Areal Flood Warning | CTP | Dauphin | 115 min |
| Sep 21, 11:59 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin, Lebanon | 28 min |
| Sep 22, 12:11 AM EDT | Areal Flood Advisory | CTP | Dauphin, Northumberland | 94 min |
| Sep 22, 12:21 AM EDT | Special Weather Statement | CTP | Adams, Cumberland, York | 54 min |
| Sep 22, 12:36 AM EDT | Areal Flood Advisory | CTP | Adams, Cumberland, York | 91 min |
| Sep 22, 12:39 AM EDT | Areal Flood Advisory | CTP | Lancaster | 81 min |
| Sep 22, 12:46 AM EDT | Special Weather Statement | CTP | Cumberland | 29 min |
| Sep 22, 1:08 AM EDT | Severe Thunderstorm Warning | CTP | Adams, York | 22 min |
| Sep 22, 1:18 AM EDT | Areal Flood Advisory | CTP | Adams, York | 89 min |
| Sep 22, 1:32 AM EDT | Special Weather Statement | CTP | Adams | 28 min |
| Sep 22, 2:35 AM EDT | Dense Fog Advisory | CTP | Bedford, Blair, Cambria, Cameron, Centre, Clearfield and 6 more | 6 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2024Every severe thunderstorm warning in 2024
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.