Alert archive / Pennsylvania / Allegheny County

Weather alerts in Allegheny County, Pennsylvania, 2011

253 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Allegheny County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts
253
Warnings
75
Watches
50
Advisories
35
Busiest month
July46 alerts
Busiest day
February 28, 201111 alerts

Over time

By month

Warning verification

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

Allegheny County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings423321%3675%24 min
Flash flood warnings4325%4100%65 min

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Pittsburgh, PA: tornado warnings9189%1100%8 min
NWS Pittsburgh, PA: severe thunderstorm warnings23116130%42883%22 min
NWS Pittsburgh, PA: flash flood warnings211148%2391%81 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 6, 10:40 PM ESTSpecial Weather StatementPBZ110 min
Jan 7, 7:09 AM ESTSpecial Weather StatementPBZ51 min
Jan 7, 7:59 AM ESTSpecial Weather StatementPBZ61 min
Jan 9, 2:36 PM ESTWinter Storm WatchPBZ25 hr
Jan 10, 3:19 PM ESTWinter Weather AdvisoryPBZ3 days
Jan 12, 3:31 PM ESTSpecial Weather StatementPBZ119 min
Jan 17, 2:20 PM ESTWinter Weather AdvisoryPBZ20 hr
Jan 19, 2:40 PM ESTWinter Weather AdvisoryPBZ37 hr
Jan 26, 7:30 AM ESTMesoscale DiscussionSPC5 hr
Jan 30, 3:30 PM ESTWinter Storm WatchPBZ19 hr
Jan 31, 10:55 AM ESTWinter Storm WarningPBZ41 hr
Feb 1, 12:12 AM ESTMesoscale DiscussionSPC5 hr
Feb 1, 3:04 PM ESTWinter Weather AdvisoryPBZ13 hr
Feb 1, 3:07 PM ESTWind AdvisoryPBZ24 hr
Feb 4, 3:46 PM ESTWinter Weather AdvisoryPBZ30 hr
Feb 7, 3:45 PM ESTWinter Weather AdvisoryPBZ20 hr
Feb 8, 7:52 AM ESTSpecial Weather StatementPBZ68 min
Feb 8, 8:57 AM ESTSpecial Weather StatementPBZ63 min
Feb 13, 2:39 PM ESTWind AdvisoryPBZ28 hr
Feb 20, 5:02 AM ESTRiver Flood AdvisoryPBZ6 hr
Feb 21, 12:08 PM ESTWinter Storm WarningPBZ18 hr
Feb 21, 12:08 PM ESTWinter Weather AdvisoryPBZ16 hr
Feb 21, 5:58 PM ESTMesoscale DiscussionSPC4 hr
Feb 23, 10:29 AM ESTFlood WatchPBZ50 hr
Feb 23, 11:05 AM ESTRiver Flood AdvisoryPBZ3 days
Feb 23, 11:20 AM ESTRiver Flood WatchPBZ47 hr
Feb 24, 10:56 AM ESTRiver Flood WatchPBZ11 hr
Feb 25, 9:34 AM ESTAreal Flood AdvisoryPBZ7 hr
Feb 27, 2:59 AM ESTFlood WatchPBZ36 hr
Feb 27, 10:46 AM ESTRiver Flood AdvisoryPBZ7 days
Feb 27, 9:34 PM ESTSevere Thunderstorm WarningPBZ41 min
Feb 27, 10:03 PM ESTSpecial Weather StatementPBZ57 min
Feb 28, 5:31 AM ESTMesoscale DiscussionSPC29 min
Feb 28, 5:47 AM ESTTornado WatchSPC5 hr
Feb 28, 6:01 AM ESTSevere Thunderstorm WarningPBZ29 min
Feb 28, 6:32 AM ESTSpecial Weather StatementPBZ28 min
Feb 28, 6:46 AM ESTAreal Flood WarningPBZ11 hr
Feb 28, 7:24 AM ESTSevere Thunderstorm WarningPBZ51 min
Feb 28, 8:04 AM ESTFlash Flood WarningPBZ4 hr
Feb 28, 10:52 AM ESTRiver Flood WatchPBZ30 hr
Feb 28, 10:52 AM ESTRiver Flood WatchPBZ30 hr
Feb 28, 10:34 PM ESTRiver Flood WarningPBZ16 hr
Feb 28, 10:34 PM ESTRiver Flood WarningPBZ8 hr
Feb 28, 10:34 PM ESTRiver Flood WarningPBZ8 hr
Feb 28, 10:34 PM ESTRiver Flood WarningPBZ11 hr
Feb 28, 10:34 PM ESTRiver Flood WarningPBZ15 hr
Mar 4, 3:47 AM ESTFlood WatchPBZ54 hr
Mar 4, 10:39 PM ESTRiver Flood WatchPBZ41 hr
Mar 4, 10:39 PM ESTRiver Flood WatchPBZ24 hr
Mar 4, 10:39 PM ESTRiver Flood WatchPBZ13 hr
Mar 4, 10:39 PM ESTRiver Flood WatchPBZ13 hr
Mar 4, 10:39 PM ESTRiver Flood WatchPBZ37 hr
Mar 6, 10:05 AM ESTRiver Flood WarningPBZ18 hr
Mar 6, 10:05 AM ESTRiver Flood WarningPBZ18 hr
Mar 6, 10:05 AM ESTRiver Flood WarningPBZ19 hr
Mar 6, 10:05 AM ESTRiver Flood WarningPBZ23 hr
Mar 6, 3:24 PM ESTRiver Flood WarningPBZ17 hr
Mar 7, 12:08 PM ESTRiver Flood AdvisoryPBZ71 hr
Mar 8, 2:21 PM ESTFlood WatchPBZ52 hr
Mar 8, 9:53 PM ESTRiver Flood WatchPBZ38 hr
Mar 8, 9:53 PM ESTRiver Flood WatchPBZ38 hr
Mar 8, 9:53 PM ESTRiver Flood WatchPBZ38 hr
Mar 8, 9:53 PM ESTRiver Flood WatchPBZ13 hr
Mar 9, 2:41 PM ESTWinter Storm WatchPBZ25 hr
Mar 9, 9:56 PM ESTRiver Flood WatchPBZ14 hr
Mar 10, 11:18 AM ESTRiver Flood WarningPBZ49 hr
Mar 10, 11:18 AM ESTRiver Flood WarningPBZ44 hr
Mar 10, 11:18 AM ESTRiver Flood WarningPBZ11 hr
Mar 10, 11:18 AM ESTRiver Flood WarningPBZ11 hr
Mar 10, 12:48 PM ESTAreal Flood WarningPBZ22 hr
Mar 10, 3:51 PM ESTWinter Storm WarningPBZ26 hr
Mar 11, 10:03 AM ESTRiver Flood WarningPBZ21 hr
Mar 11, 10:47 AM ESTAreal Flood WarningPBZ11 hr
Mar 12, 3:28 PM ESTRiver Flood AdvisoryPBZ7 days
Mar 21, 4:03 AM EDTSpecial Weather StatementPBZ57 min
Mar 23, 1:13 PM EDTTornado WatchSPC7 hr
Mar 23, 3:36 PM EDTSevere Thunderstorm WarningPBZ54 min
Mar 23, 3:54 PM EDTMesoscale DiscussionSPC96 min
Mar 23, 4:18 PM EDTSevere Thunderstorm WarningPBZ27 min
Mar 23, 4:34 PM EDTSevere Thunderstorm WarningPBZ56 min
Mar 23, 4:42 PM EDTSevere Thunderstorm WarningPBZ63 min
Mar 23, 4:55 PM EDTSevere Thunderstorm WarningPBZ65 min
Mar 23, 5:14 PM EDTSevere Thunderstorm WarningPBZ47 min
Mar 23, 5:22 PM EDTSevere Thunderstorm WarningPBZ42 min
Mar 23, 5:26 PM EDTSevere Thunderstorm WarningPBZ39 min
Apr 3, 6:25 PM EDTSpecial Weather StatementPBZ35 min
Apr 4, 10:59 AM EDTSpecial Weather StatementPBZ2 hr
Apr 4, 2:55 PM EDTSpecial Weather StatementPBZ65 min
Apr 4, 4:12 PM EDTMesoscale DiscussionSPC63 min
Apr 4, 6:00 PM EDTMesoscale DiscussionSPC90 min
Apr 5, 11:16 AM EDTRiver Flood AdvisoryPBZ5 days
Apr 11, 9:48 PM EDTRiver Flood AdvisoryPBZ13 hr
Apr 12, 10:20 PM EDTRiver Flood AdvisoryPBZ6 days
Apr 16, 4:01 PM EDTWind AdvisoryPBZ27 hr
Apr 19, 4:13 PM EDTRiver Flood AdvisoryPBZ11 days
Apr 19, 8:16 PM EDTSpecial Weather StatementPBZ44 min
Apr 20, 2:22 AM EDTSevere Thunderstorm WatchSPC3 hr
Apr 20, 3:20 AM EDTMesoscale DiscussionSPC85 min
Apr 21, 2:55 PM EDTFlash Flood WatchPBZ53 hr
Apr 25, 1:52 PM EDTMesoscale DiscussionSPC83 min
Apr 25, 2:47 PM EDTSevere Thunderstorm WatchSPC7 hr
Apr 25, 5:59 PM EDTSpecial Weather StatementPBZ31 min
Apr 25, 6:00 PM EDTMesoscale DiscussionSPC60 min
Apr 25, 6:36 PM EDTSpecial Weather StatementPBZ24 min
Apr 26, 12:55 PM EDTSevere Thunderstorm WarningPBZ35 min
Apr 26, 1:18 PM EDTMesoscale DiscussionSPC57 min
Apr 26, 1:30 PM EDTSevere Thunderstorm WarningPBZ45 min
Apr 26, 1:49 PM EDTSevere Thunderstorm WatchSPC7 hr
Apr 26, 3:50 PM EDTSevere Thunderstorm WarningPBZ40 min
Apr 27, 10:09 AM EDTFlash Flood WatchPBZ18 hr
Apr 27, 1:24 PM EDTMesoscale DiscussionSPC96 min
Apr 27, 3:10 PM EDTTornado WatchSPC7 hr
Apr 27, 3:18 PM EDTSpecial Weather StatementPBZ57 min
Apr 27, 4:06 PM EDTSpecial Weather StatementPBZ54 min
Apr 27, 4:32 PM EDTSevere Thunderstorm WarningPBZ58 min
Apr 28, 5:22 AM EDTWind AdvisoryPBZ6 hr
May 4, 4:04 PM EDTFrost AdvisoryPBZ17 hr
May 6, 7:04 PM EDTSpecial Weather StatementPBZ56 min
May 10, 10:19 PM EDTSevere Thunderstorm WarningPBZ28 min
May 12, 4:59 PM EDTSpecial Weather StatementPBZ31 min
May 12, 5:32 PM EDTSpecial Weather StatementPBZ58 min
May 12, 7:45 PM EDTSpecial Weather StatementPBZ60 min
May 12, 8:42 PM EDTAreal Flood WarningPBZ3 hr
May 13, 1:19 PM EDTSpecial Weather StatementPBZ116 min
May 13, 2:52 PM EDTSevere Thunderstorm WarningPBZ38 min
May 13, 3:41 PM EDTSpecial Weather StatementPBZ49 min
May 13, 3:43 PM EDTSpecial Weather StatementPBZ47 min
May 13, 3:49 PM EDTAreal Flood WarningPBZ6 hr
May 13, 3:52 PM EDTFlood WatchPBZ6 hr
May 14, 4:10 AM EDTFlash Flood WatchPBZ20 hr
May 14, 6:49 PM EDTSpecial Weather StatementPBZ41 min
May 17, 10:02 PM EDTRiver Flood AdvisoryPBZ64 hr
May 18, 2:41 AM EDTFlood WatchPBZ16 hr
May 18, 7:25 AM EDTSpecial Weather StatementPBZ50 min
May 18, 11:55 AM EDTMesoscale DiscussionSPC65 min
May 18, 11:56 AM EDTSpecial Weather StatementPBZ49 min
May 18, 12:55 PM EDTSevere Thunderstorm WatchSPC8 hr
May 18, 1:51 PM EDTSpecial Weather StatementPBZ54 min
May 18, 3:08 PM EDTMesoscale DiscussionSPC67 min
May 18, 4:34 PM EDTSpecial Weather StatementPBZ41 min
May 18, 4:38 PM EDTSpecial Weather StatementPBZ37 min
May 18, 6:01 PM EDTMesoscale DiscussionSPC89 min
May 23, 8:07 PM EDTMesoscale DiscussionSPC83 min
May 23, 8:31 PM EDTSevere Thunderstorm WatchSPC3 hr
May 25, 9:42 PM EDTSevere Thunderstorm WarningPBZ63 min
May 26, 4:20 PM EDTSevere Thunderstorm WarningPBZ40 min
May 26, 4:53 PM EDTSevere Thunderstorm WarningPBZ52 min
May 26, 6:06 PM EDTSevere Thunderstorm WatchSPC6 hr
Jun 4, 6:13 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 4, 8:58 PM EDTMesoscale DiscussionSPC2 hr
Jun 7, 9:35 AM EDTSpecial Weather StatementPBZ40 min
Jun 9, 3:56 AM EDTSevere Thunderstorm WatchSPC6 hr
Jun 9, 10:36 AM EDTMesoscale DiscussionSPC84 min
Jun 9, 11:33 AM EDTMesoscale DiscussionSPC57 min
Jun 9, 12:53 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 10, 1:32 PM EDTSpecial Weather StatementPBZ28 min
Jun 10, 1:56 PM EDTSpecial Weather StatementPBZ34 min
Jun 10, 2:30 PM EDTAreal Flood AdvisoryPBZ3 hr
Jun 16, 6:01 PM EDTMesoscale DiscussionSPC89 min
Jun 19, 1:55 PM EDTFlash Flood WatchPBZ15 hr
Jun 20, 12:25 AM EDTSpecial Weather StatementPBZ65 min
Jun 20, 12:38 AM EDTFlash Flood WarningPBZ3 hr
Jun 23, 12:33 PM EDTMesoscale DiscussionSPC117 min
Jun 23, 3:58 PM EDTSpecial Weather StatementPBZ62 min
Jun 28, 1:19 PM EDTMesoscale DiscussionSPC86 min
Jul 4, 5:35 PM EDTAreal Flood WarningPBZ3 hr
Jul 4, 6:44 PM EDTSevere Thunderstorm WarningPBZ32 min
Jul 4, 7:11 PM EDTFlash Flood WarningPBZ3 hr
Jul 7, 1:52 PM EDTSpecial Weather StatementPBZ38 min
Jul 11, 1:42 PM EDTMesoscale DiscussionSPC93 min
Jul 11, 2:16 PM EDTSevere Thunderstorm WatchSPC6 hr
Jul 11, 3:43 PM EDTMesoscale DiscussionSPC92 min
Jul 11, 4:16 PM EDTSevere Thunderstorm WarningPBZ44 min
Jul 11, 5:00 PM EDTSevere Thunderstorm WarningPBZ60 min
Jul 11, 5:14 PM EDTSevere Thunderstorm WarningPBZ61 min
Jul 18, 1:18 PM EDTMesoscale DiscussionSPC117 min
Jul 18, 3:29 PM EDTSevere Thunderstorm WarningPBZ46 min
Jul 18, 3:57 PM EDTSevere Thunderstorm WatchSPC6 hr
Jul 18, 4:21 PM EDTSpecial Weather StatementPBZ39 min
Jul 18, 5:12 PM EDTSpecial Weather StatementPBZ48 min
Jul 18, 5:22 PM EDTSevere Thunderstorm WarningPBZ38 min
Jul 18, 5:39 PM EDTSpecial Weather StatementPBZ51 min
Jul 18, 5:59 PM EDTAreal Flood WarningPBZ4 hr
Jul 18, 6:11 PM EDTSevere Thunderstorm WarningPBZ64 min
Jul 18, 7:12 PM EDTSevere Thunderstorm WarningPBZ48 min
Jul 18, 8:02 PM EDTMesoscale DiscussionSPC58 min
Jul 20, 4:00 AM EDTExcessive Heat WatchPBZ8 hr
Jul 20, 11:32 AM EDTExcessive Heat WarningPBZ30 hr
Jul 21, 3:34 PM EDTHeat AdvisoryPBZ26 hr
Jul 22, 11:36 AM EDTExcessive Heat WarningPBZ6 hr
Jul 22, 3:17 PM EDTMesoscale DiscussionSPC58 min
Jul 22, 5:06 PM EDTSevere Thunderstorm WarningPBZ39 min
Jul 22, 5:12 PM EDTSevere Thunderstorm WarningPBZ63 min
Jul 22, 5:19 PM EDTMesoscale DiscussionSPC56 min
Jul 22, 5:37 PM EDTSevere Thunderstorm WatchSPC4 hr
Jul 22, 6:00 PM EDTSevere Thunderstorm WarningPBZ45 min
Jul 22, 6:15 PM EDTAreal Flood WarningPBZ4 hr
Jul 22, 8:13 PM EDTMesoscale DiscussionSPC62 min
Jul 25, 11:31 AM EDTAreal Flood AdvisoryPBZ3 hr
Jul 25, 11:37 AM EDTSevere Thunderstorm WatchSPC7 hr
Jul 25, 3:15 PM EDTSpecial Weather StatementPBZ45 min
Jul 25, 3:16 PM EDTMesoscale DiscussionSPC59 min
Jul 28, 3:43 PM EDTMesoscale DiscussionSPC62 min
Jul 28, 4:03 PM EDTSevere Thunderstorm WatchSPC6 hr
Jul 28, 5:20 PM EDTSevere Thunderstorm WarningPBZ40 min
Jul 28, 5:59 PM EDTSevere Thunderstorm WarningPBZ46 min
Jul 28, 6:16 PM EDTSevere Thunderstorm WarningPBZ59 min
Jul 28, 7:02 PM EDTMesoscale DiscussionSPC58 min
Jul 28, 7:10 PM EDTAreal Flood AdvisoryPBZ3 hr
Jul 28, 7:53 PM EDTSpecial Weather StatementPBZ37 min
Jul 29, 2:06 PM EDTMesoscale DiscussionSPC84 min
Aug 1, 5:03 PM EDTSpecial Weather StatementPBZ27 min
Aug 1, 5:47 PM EDTSpecial Weather StatementPBZ28 min
Aug 19, 9:30 AM EDTSpecial Weather StatementPBZ60 min
Aug 19, 10:33 AM EDTSevere Thunderstorm WarningPBZ57 min
Aug 19, 2:54 PM EDTSpecial Weather StatementPBZ36 min
Aug 19, 3:19 PM EDTSevere Thunderstorm WarningPBZ56 min
Aug 19, 3:24 PM EDTSevere Thunderstorm WarningPBZ66 min
Aug 19, 3:56 PM EDTSevere Thunderstorm WarningPBZ64 min
Aug 19, 4:03 PM EDTSpecial Weather StatementPBZ27 min
Aug 19, 4:19 PM EDTSevere Thunderstorm WarningPBZ36 min
Aug 19, 4:24 PM EDTFlash Flood WarningPBZ3 hr
Aug 19, 4:48 PM EDTSevere Thunderstorm WarningPBZ57 min
Aug 19, 4:52 PM EDTFlash Flood WatchPBZ3 hr
Aug 21, 3:26 PM EDTSpecial Weather StatementPBZ49 min
Aug 21, 4:13 PM EDTSevere Thunderstorm WarningPBZ62 min
Aug 24, 11:48 PM EDTMesoscale DiscussionSPC87 min
Aug 25, 12:42 AM EDTSevere Thunderstorm WatchSPC5 hr
Aug 25, 2:31 AM EDTMesoscale DiscussionSPC119 min
Sep 3, 6:19 PM EDTSpecial Weather StatementPBZ26 min
Sep 3, 6:41 PM EDTSevere Thunderstorm WarningPBZ19 min
Sep 5, 10:29 PM EDTRiver Flood WatchPBZ24 hr
Sep 5, 10:29 PM EDTRiver Flood WatchPBZ24 hr
Sep 5, 10:50 PM EDTRiver Flood AdvisoryPBZ30 hr
Sep 10, 4:38 PM EDTSpecial Weather StatementPBZ52 min
Sep 11, 6:36 PM EDTSpecial Weather StatementPBZ39 min
Sep 23, 9:57 PM EDTDense Fog AdvisoryPBZ11 hr
Sep 25, 6:34 PM EDTMesoscale DiscussionSPC86 min
Sep 26, 11:24 PM EDTSpecial Weather StatementPBZ51 min
Oct 13, 7:52 PM EDTSpecial Weather StatementPBZ38 min
Oct 19, 8:13 PM EDTSpecial Weather StatementPBZ32 min
Oct 22, 4:12 AM EDTFrost AdvisoryPBZ29 hr
Oct 28, 6:48 AM EDTDense Fog AdvisoryPBZ2 hr
Oct 29, 11:43 PM EDTDense Fog AdvisoryPBZ11 hr
Nov 14, 8:41 PM ESTMesoscale DiscussionSPC2 hr
Nov 14, 8:58 PM ESTSpecial Weather StatementPBZ47 min
Nov 14, 9:48 PM ESTSpecial Weather StatementPBZ57 min
Nov 21, 11:30 AM ESTRiver Flood AdvisoryPBZ4 days
Nov 22, 11:05 AM ESTFlood WatchPBZ13 hr
Nov 23, 7:27 AM ESTRiver Flood WarningPBZ20 hr
Nov 28, 5:41 AM ESTRiver Flood AdvisoryPBZ16 hr
Dec 15, 4:51 PM ESTSpecial Weather StatementPBZ69 min
Dec 27, 4:21 AM ESTWinter Weather AdvisoryPBZ24 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 archive20102012

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.