Alert archive / Pennsylvania / Somerset County

Weather alerts in Somerset County, Pennsylvania, 2021

122 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Somerset County and its neighbors

Each county as a circle sized by its count in 2021. Tap one for its archive.

Alerts
122
Warnings
27
Watches
24
Advisories
25
Busiest month
July26 alerts
Busiest day
July 13, 20219 alerts

Over time

By month

Warning verification

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

1 of 1 tornado warnings covering Somerset County in 2021 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 14 minutes after it went out.

Somerset County, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings110%1100%14 min
Severe thunderstorm warnings121017%1275%21 min
Flash flood warnings220%580%226 min

Each office's whole area, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS State College, PA: tornado warnings11373%1225%7 min
NWS State College, PA: severe thunderstorm warnings28921227%45887%23 min
NWS State College, PA: flash flood warnings312035%4689%118 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 1, 2:36 AM ESTIce Storm WarningCTP20 hr
Jan 2, 3:16 PM ESTWinter Weather AdvisoryCTP32 hr
Jan 16, 12:31 PM ESTSpecial Weather StatementCTP119 min
Jan 16, 1:53 PM ESTWinter Weather AdvisoryCTP17 hr
Jan 19, 3:00 AM ESTWinter Weather AdvisoryCTP34 hr
Jan 20, 5:29 AM ESTSpecial Weather StatementCTP61 min
Jan 24, 3:44 AM ESTWinter Storm WatchCTP24 hr
Jan 25, 3:29 AM ESTWinter Storm WarningCTP33 hr
Jan 26, 8:46 AM ESTMesoscale DiscussionSPC4 hr
Jan 29, 8:54 PM ESTWinter Storm WatchCTP19 hr
Jan 30, 3:24 PM ESTWinter Storm WarningCTP13 hr
Jan 31, 4:52 AM ESTWinter Storm WarningCTP48 hr
Feb 2, 6:57 PM ESTWinter Weather AdvisoryCTP12 hr
Feb 10, 4:33 AM ESTWinter Weather AdvisoryCTP28 hr
Feb 13, 2:53 PM ESTWinter Weather AdvisoryCTP17 hr
Feb 14, 3:46 PM ESTWinter Storm WatchCTP13 hr
Feb 14, 3:46 PM ESTWinter Weather AdvisoryCTP38 hr
Feb 15, 2:44 PM ESTMesoscale DiscussionSPC6 hr
Feb 15, 3:28 PM ESTIce Storm WarningCTP15 hr
Feb 16, 3:35 PM ESTWinter Storm WatchCTP23 hr
Feb 17, 2:39 PM ESTWinter Weather AdvisoryCTP22 hr
Feb 21, 2:29 PM ESTWinter Weather AdvisoryCTP23 hr
Feb 27, 2:29 PM ESTFlood WatchCTP39 hr
Feb 28, 2:46 PM ESTAreal Flood AdvisoryCTP17 hr
Feb 28, 3:14 PM ESTAreal Flood WarningCTP6 hr
Mar 1, 3:40 AM ESTWind AdvisoryCTP23 hr
Mar 1, 8:04 AM ESTRiver Flood WarningCTP6 hr
Mar 1, 7:02 PM ESTSpecial Weather StatementCTP28 min
Mar 15, 2:36 PM EDTWinter Weather AdvisoryCTP20 hr
Mar 24, 1:45 PM EDTHigh Wind WatchCTP25 hr
Mar 25, 2:29 PM EDTHigh Wind WarningCTP28 hr
Apr 1, 4:25 PM EDTSpecial Weather StatementCTP50 min
Apr 1, 8:51 PM EDTSpecial Weather StatementCTP54 min
Apr 29, 2:33 PM EDTFreeze WatchCTP24 hr
Apr 29, 8:21 PM EDTWind AdvisoryCTP30 hr
Apr 30, 2:26 PM EDTFreeze WarningCTP18 hr
May 8, 4:05 AM EDTFrost AdvisoryCTP28 hr
May 11, 2:58 PM EDTFreeze WatchCTP3 hr
May 12, 3:58 AM EDTFrost AdvisoryCTP28 hr
May 26, 12:16 PM EDTMesoscale DiscussionSPC119 min
May 26, 12:59 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 10, 11:47 AM EDTFlash Flood WatchCTP9 hr
Jun 13, 8:56 AM EDTSpecial Weather StatementCTP49 min
Jun 13, 9:08 AM EDTSevere Thunderstorm WarningCTP67 min
Jun 13, 10:04 AM EDTAreal Flood AdvisoryCTP116 min
Jun 13, 12:13 PM EDTMesoscale DiscussionSPC2 hr
Jun 13, 3:26 PM EDTMesoscale DiscussionSPC94 min
Jun 14, 11:31 AM EDTMesoscale DiscussionSPC89 min
Jun 14, 11:46 AM EDTSevere Thunderstorm WatchSPC6 hr
Jun 14, 3:25 PM EDTMesoscale DiscussionSPC95 min
Jun 14, 4:16 PM EDTSpecial Weather StatementCTP14 min
Jun 14, 4:44 PM EDTSpecial Weather StatementCTP16 min
Jun 14, 5:04 PM EDTSpecial Weather StatementCTP26 min
Jun 14, 5:49 PM EDTSpecial Weather StatementCTP26 min
Jun 21, 12:31 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 21, 1:51 PM EDTMesoscale DiscussionSPC114 min
Jun 21, 4:39 PM EDTSevere Thunderstorm WarningCTP36 min
Jun 21, 7:00 PM EDTSpecial Weather StatementCTP15 min
Jun 28, 6:16 PM EDTSpecial Weather StatementCTP29 min
Jun 28, 6:58 PM EDTSpecial Weather StatementCTP47 min
Jun 30, 11:30 AM EDTMesoscale DiscussionSPC2 hr
Jun 30, 12:46 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 30, 3:29 PM EDTMesoscale DiscussionSPC2 hr
Jun 30, 3:59 PM EDTSpecial Weather StatementCTP46 min
Jun 30, 4:41 PM EDTMesoscale DiscussionSPC2 hr
Jul 7, 4:05 PM EDTSpecial Weather StatementCTP25 min
Jul 7, 4:12 PM EDTSpecial Weather StatementCTP33 min
Jul 7, 4:12 PM EDTSevere Thunderstorm WarningCTP47 min
Jul 7, 4:22 PM EDTSevere Thunderstorm WarningCTP38 min
Jul 7, 4:54 PM EDTSevere Thunderstorm WarningCTP51 min
Jul 7, 8:40 PM EDTSevere Thunderstorm WarningCTP65 min
Jul 11, 2:05 PM EDTMesoscale DiscussionSPC55 min
Jul 11, 2:40 PM EDTSevere Thunderstorm WatchSPC8 hr
Jul 11, 5:25 PM EDTSevere Thunderstorm WarningCTP65 min
Jul 11, 5:41 PM EDTMesoscale DiscussionSPC94 min
Jul 11, 6:03 PM EDTSevere Thunderstorm WarningCTP57 min
Jul 13, 1:37 PM EDTSevere Thunderstorm WatchSPC10 hr
Jul 13, 4:07 PM EDTMesoscale DiscussionSPC113 min
Jul 13, 4:18 PM EDTSpecial Weather StatementCTP42 min
Jul 13, 4:34 PM EDTSevere Thunderstorm WarningCTP41 min
Jul 13, 4:38 PM EDTAreal Flood AdvisoryCTP3 hr
Jul 13, 5:14 PM EDTSpecial Weather StatementCTP46 min
Jul 13, 5:38 PM EDTSevere Thunderstorm WarningCTP41 min
Jul 13, 6:27 PM EDTSevere Thunderstorm WarningCTP37 min
Jul 13, 7:08 PM EDTSpecial Weather StatementCTP37 min
Jul 17, 1:13 PM EDTSevere Thunderstorm WatchSPC10 hr
Jul 17, 3:04 PM EDTSevere Thunderstorm WarningCTP56 min
Jul 17, 4:50 PM EDTSpecial Weather StatementCTP25 min
Jul 28, 4:42 PM EDTSpecial Weather StatementCTP48 min
Jul 29, 2:13 PM EDTTornado WarningCTP32 min
Jul 29, 3:13 PM EDTSevere Thunderstorm WatchSPC7 hr
Aug 10, 3:12 PM EDTSpecial Weather StatementCTP33 min
Aug 11, 11:50 AM EDTMesoscale DiscussionSPC115 min
Aug 11, 2:03 PM EDTMesoscale DiscussionSPC87 min
Aug 11, 2:59 PM EDTSpecial Weather StatementCTP61 min
Aug 11, 3:02 PM EDTSevere Thunderstorm WatchSPC6 hr
Aug 12, 1:11 PM EDTSevere Thunderstorm WatchSPC9 hr
Aug 13, 7:49 PM EDTMesoscale DiscussionSPC56 min
Aug 17, 2:13 PM EDTFlash Flood WatchCTP34 hr
Aug 18, 11:37 AM EDTTornado WatchSPC11 hr
Aug 21, 6:27 PM EDTAreal Flood AdvisoryCTP2 hr
Aug 26, 5:34 PM EDTSpecial Weather StatementCTP26 min
Aug 28, 5:29 PM EDTAreal Flood AdvisoryCTP44 min
Aug 29, 6:02 PM EDTAreal Flood AdvisoryCTP58 min
Aug 29, 7:26 PM EDTSpecial Weather StatementCTP19 min
Aug 29, 7:45 PM EDTSpecial Weather StatementCTP15 min
Aug 30, 4:11 AM EDTFlash Flood WatchCTP67 hr
Aug 31, 12:12 PM EDTRiver Flood WarningCTP61 hr
Sep 1, 8:54 AM EDTFlash Flood Warning Considerable damage threatCTP8 hr
Sep 1, 9:37 AM EDTFlash Flood Warning Considerable damage threatCTP6 hr
Sep 1, 3:34 PM EDTAreal Flood WarningCTP6 hr
Sep 1, 4:40 PM EDTAreal Flood WarningCTP6 hr
Sep 15, 10:33 AM EDTMesoscale DiscussionSPC2 hr
Sep 15, 11:55 AM EDTSevere Thunderstorm WatchSPC8 hr
Sep 22, 3:42 AM EDTFlash Flood WatchCTP33 hr
Oct 14, 3:10 AM EDTDense Fog AdvisoryCTP6 hr
Oct 28, 1:58 PM EDTWind AdvisoryCTP27 hr
Dec 2, 12:08 PM ESTWind AdvisoryCTP16 hr
Dec 10, 11:15 AM ESTWind AdvisoryCTP38 hr
Dec 11, 11:20 AM ESTSpecial Weather StatementCTP40 min
Dec 26, 2:58 PM ESTWinter Weather AdvisoryCTP33 hr
Dec 27, 6:58 AM ESTMesoscale DiscussionSPC5 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 archive20202022

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.