Alert archive / Pennsylvania / Union County

Weather alerts in Union County, Pennsylvania, 2024

146 weather alerts in 2024, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Union County and its neighbors

Each county as a circle sized by its count in 2024. Tap one for its archive.

Alerts
146
Warnings
36
Watches
23
Advisories
38
Busiest month
August28 alerts
Busiest day
August 9, 20247 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Union County, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings141121%367%5 min
Flash flood warnings2150%2100%71 min

Each office's whole area, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS State College, PA: tornado warnings160100%40%
NWS State College, PA: severe thunderstorm warnings18812534%42274%20 min
NWS State College, PA: flash flood warnings332330%6578%59 min

An office's figures cover every county it serves, including across state lines.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

The alerts

Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 4, 2:29 PM ESTWinter Storm WatchCTP22 hr
Jan 5, 12:23 PM ESTWinter Storm WarningCTP37 hr
Jan 6, 11:47 AM ESTMesoscale DiscussionSPC5 hr
Jan 6, 4:27 PM ESTMesoscale DiscussionSPC5 hr
Jan 8, 2:14 AM ESTFlood WatchCTP49 hr
Jan 8, 4:08 AM ESTWind AdvisoryCTP62 hr
Jan 9, 10:52 PM ESTAreal Flood AdvisoryCTP4 hr
Jan 12, 4:14 AM ESTWind AdvisoryCTP41 hr
Jan 14, 2:34 AM ESTWind AdvisoryCTP14 hr
Jan 14, 8:12 AM ESTSnow Squall WarningCTP33 min
Jan 14, 8:25 AM ESTMesoscale DiscussionSPC4 hr
Jan 14, 8:26 AM ESTSnow Squall WarningCTP64 min
Jan 14, 9:29 AM ESTSnow Squall WarningCTP31 min
Jan 14, 10:05 AM ESTSnow Squall Warning Significant damage threatCTP25 min
Jan 15, 4:01 AM ESTWinter Weather AdvisoryCTP34 hr
Jan 18, 4:25 AM ESTWinter Weather AdvisoryCTP66 hr
Jan 22, 10:03 AM ESTWinter Weather AdvisoryCTP33 hr
Jan 25, 10:43 AM ESTDense Fog AdvisoryCTP22 hr
Feb 10, 2:46 PM ESTWinter Storm WatchCTP48 hr
Feb 11, 2:49 PM ESTWinter Storm WarningCTP43 hr
Feb 15, 3:50 PM ESTWind AdvisoryCTP18 hr
Feb 16, 3:03 AM ESTWinter Weather AdvisoryCTP28 hr
Feb 16, 10:33 PM ESTMesoscale DiscussionSPC4 hr
Feb 17, 11:34 AM ESTMesoscale DiscussionSPC5 hr
Feb 27, 2:47 PM ESTWind AdvisoryCTP37 hr
Mar 8, 6:40 AM ESTDense Fog AdvisoryCTP3 hr
Mar 9, 3:20 AM ESTWind AdvisoryCTP62 hr
Mar 10, 12:13 PM EDTMesoscale DiscussionSPC4 hr
Mar 10, 5:54 PM EDTSnow Squall WarningCTP51 min
Apr 1, 2:08 PM EDTFlood WatchCTP60 hr
Apr 3, 8:43 AM EDTAreal Flood AdvisoryCTP3 hr
Apr 3, 12:04 PM EDTRiver Flood WarningCTP19 hr
Apr 4, 3:06 PM EDTRiver Flood WarningCTP8 hr
Apr 12, 10:25 AM EDTWind AdvisoryCTP32 hr
Apr 14, 3:29 PM EDTMesoscale DiscussionSPC2 hr
Apr 14, 4:58 PM EDTSevere Thunderstorm WatchSPC6 hr
Apr 14, 6:46 PM EDTMesoscale DiscussionSPC89 min
Apr 14, 7:05 PM EDTSevere Thunderstorm WarningCTP25 min
Apr 14, 7:10 PM EDTSevere Thunderstorm WarningCTP35 min
Apr 20, 11:26 AM EDTFrost AdvisoryCTP21 hr
Apr 21, 3:41 AM EDTFreeze WatchCTP8 hr
Apr 21, 11:54 AM EDTFreeze WarningCTP20 hr
Apr 22, 9:45 AM EDTFrost AdvisoryCTP22 hr
Apr 23, 3:01 PM EDTFreeze WatchCTP23 hr
Apr 24, 1:53 PM EDTFreeze WarningCTP18 hr
Apr 25, 1:32 PM EDTFrost AdvisoryCTP18 hr
Apr 30, 1:12 PM EDTMesoscale DiscussionSPC3 hr
May 16, 6:04 AM EDTDense Fog AdvisoryCTP3 hr
May 20, 5:18 AM EDTDense Fog AdvisoryCTP4 hr
May 22, 2:29 PM EDTSpecial Weather StatementCTP31 min
May 22, 3:00 PM EDTSevere Thunderstorm WatchSPC5 hr
May 22, 4:39 PM EDTMesoscale DiscussionSPC2 hr
May 23, 5:35 AM EDTSevere Thunderstorm Warning Considerable damage threatCTP40 min
May 23, 6:08 AM EDTSevere Thunderstorm WarningCTP52 min
May 23, 7:32 AM EDTAreal Flood AdvisoryCTP3 hr
May 26, 12:09 AM EDTDense Fog AdvisoryCTP10 hr
May 27, 11:53 AM EDTMesoscale DiscussionSPC2 hr
May 27, 1:42 PM EDTSevere Thunderstorm WatchSPC7 hr
May 27, 4:40 PM EDTMesoscale DiscussionSPC95 min
May 29, 2:30 PM EDTAreal Flood AdvisoryCTP90 min
Jun 14, 2:34 PM EDTMesoscale DiscussionSPC116 min
Jun 16, 3:20 PM EDTHeat AdvisoryCTP7 days
Jun 17, 7:50 PM EDTMesoscale DiscussionSPC55 min
Jun 21, 11:38 AM EDTMesoscale DiscussionSPC2 hr
Jun 22, 7:20 PM EDTSpecial Weather StatementCTP25 min
Jun 22, 7:47 PM EDTSevere Thunderstorm WarningCTP43 min
Jun 23, 3:23 PM EDTMesoscale DiscussionSPC2 hr
Jun 23, 4:33 PM EDTSevere Thunderstorm WatchSPC5 hr
Jun 23, 7:15 PM EDTSpecial Weather StatementCTP30 min
Jun 23, 7:20 PM EDTMesoscale DiscussionSPC115 min
Jun 23, 9:03 PM EDTSpecial Weather StatementCTP27 min
Jun 26, 12:32 PM EDTMesoscale DiscussionSPC2 hr
Jun 26, 1:11 PM EDTSevere Thunderstorm WatchSPC8 hr
Jun 26, 4:02 PM EDTMesoscale DiscussionSPC118 min
Jun 26, 5:35 PM EDTSevere Thunderstorm WarningCTP40 min
Jun 29, 3:42 AM EDTFlood WatchCTP15 hr
Jun 29, 1:11 PM EDTTornado WatchSPC7 hr
Jun 29, 4:09 PM EDTMesoscale DiscussionSPC96 min
Jun 29, 4:13 PM EDTSevere Thunderstorm WarningCTP47 min
Jun 30, 11:09 AM EDTSevere Thunderstorm WatchSPC10 hr
Jun 30, 12:55 PM EDTSevere Thunderstorm WarningCTP35 min
Jun 30, 1:07 PM EDTSevere Thunderstorm WarningCTP26 min
Jun 30, 1:30 PM EDTSevere Thunderstorm WarningCTP45 min
Jul 7, 2:40 PM EDTHeat AdvisoryCTP3 days
Jul 10, 12:06 PM EDTTornado WatchSPC11 hr
Jul 10, 6:02 PM EDTSevere Thunderstorm WarningCTP43 min
Jul 10, 7:17 PM EDTMesoscale DiscussionSPC88 min
Jul 10, 8:06 PM EDTSpecial Weather StatementCTP24 min
Jul 13, 2:42 AM EDTHeat AdvisoryCTP4 days
Jul 16, 2:35 PM EDTMesoscale DiscussionSPC115 min
Jul 24, 8:15 PM EDTSevere Thunderstorm WarningCTP45 min
Jul 30, 12:39 PM EDTMesoscale DiscussionSPC2 hr
Aug 1, 4:50 PM EDTSpecial Weather StatementCTP10 min
Aug 3, 12:14 PM EDTFlood WatchCTP9 hr
Aug 6, 10:59 AM EDTMesoscale DiscussionSPC91 min
Aug 6, 11:42 AM EDTSevere Thunderstorm WatchSPC7 hr
Aug 6, 2:10 PM EDTMesoscale DiscussionSPC95 min
Aug 6, 4:29 PM EDTMesoscale DiscussionSPC61 min
Aug 7, 3:24 PM EDTFlood WatchCTP48 hr
Aug 9, 6:05 AM EDTSpecial Weather StatementCTP25 min
Aug 9, 6:17 AM EDTTornado WatchSPC8 hr
Aug 9, 6:28 AM EDTSpecial Weather StatementCTP32 min
Aug 9, 7:06 AM EDTFlash Flood WarningCTP2 hr
Aug 9, 9:30 AM EDTAreal Flood WarningCTP11 hr
Aug 9, 10:22 AM EDTRiver Flood WarningCTP22 hr
Aug 9, 10:26 AM EDTMesoscale DiscussionSPC94 min
Aug 9, 11:28 PM EDTRiver Flood WarningCTP37 hr
Aug 10, 12:05 AM EDTRiver Flood WarningCTP40 hr
Aug 10, 12:14 AM EDTRiver Flood WarningCTP37 hr
Aug 17, 4:59 AM EDTFlood WatchCTP42 hr
Aug 18, 1:09 PM EDTMesoscale DiscussionSPC96 min
Aug 18, 1:42 PM EDTSpecial Weather StatementCTP33 min
Aug 18, 4:30 PM EDTMesoscale DiscussionSPC90 min
Aug 28, 6:19 PM EDTSpecial Weather StatementCTP41 min
Aug 29, 2:34 PM EDTFlood WatchCTP9 hr
Aug 29, 5:40 PM EDTMesoscale DiscussionSPC95 min
Aug 29, 6:00 PM EDTSpecial Weather StatementCTP30 min
Aug 29, 6:21 PM EDTAreal Flood AdvisoryCTP84 min
Aug 29, 7:39 PM EDTSevere Thunderstorm WarningCTP51 min
Aug 29, 8:28 PM EDTSevere Thunderstorm WarningCTP47 min
Sep 4, 7:07 AM EDTSpecial Weather StatementCTP83 min
Sep 5, 4:46 AM EDTSpecial Weather StatementCTP4 hr
Sep 21, 2:37 PM EDTMesoscale DiscussionSPC2 hr
Sep 21, 10:21 PM EDTAreal Flood AdvisoryCTP2 hr
Sep 21, 10:44 PM EDTFlash Flood WarningCTP2 hr
Sep 21, 11:11 PM EDTAreal Flood AdvisoryCTP2 hr
Oct 2, 10:27 PM EDTDense Fog AdvisoryCTP12 hr
Oct 10, 3:04 AM EDTFrost AdvisoryCTP30 hr
Oct 13, 9:27 PM EDTSpecial Weather StatementCTP18 min
Oct 14, 2:34 PM EDTFrost AdvisoryCTP18 hr
Oct 15, 12:36 PM EDTFrost AdvisoryCTP20 hr
Oct 16, 1:44 PM EDTFreeze WarningCTP19 hr
Nov 1, 4:09 AM EDTFire Weather WatchCTP6 hr
Nov 1, 9:53 AM EDTRed Flag WarningCTP9 hr
Nov 7, 1:57 PM ESTFire Weather WatchCTP18 hr
Nov 7, 1:57 PM ESTRed Flag WarningCTP28 hr
Nov 20, 11:39 AM ESTWinter Weather AdvisoryCTP52 hr
Dec 3, 2:37 PM ESTWind AdvisoryCTP52 hr
Dec 3, 3:38 PM ESTSpecial Weather StatementCTP67 min
Dec 5, 4:49 AM ESTSnow Squall WarningCTP56 min
Dec 5, 5:48 AM ESTSpecial Weather StatementCTP72 min
Dec 5, 6:23 AM ESTSpecial Weather StatementCTP52 min
Dec 9, 9:44 PM ESTDense Fog AdvisoryCTP11 hr
Dec 12, 4:17 AM ESTSpecial Weather StatementCTP58 min
Dec 14, 3:30 AM ESTWinter Weather AdvisoryCTP55 hr
Dec 28, 5:40 PM ESTDense Fog AdvisoryCTP15 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20232025

Sources

National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.