Alert archive / Pennsylvania / Dauphin County

Weather alerts in Dauphin County, Pennsylvania, 2009

172 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Dauphin County and its neighbors

Each county as a circle sized by its count in 2009. Tap one for its archive.

Alerts
172
Warnings
41
Watches
21
Advisories
51
Busiest month
August42 alerts
Busiest day
June 9, 20098 alerts

Over time

By month

Warning verification

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

0 of 1 tornado warnings covering Dauphin County in 2009 had a tornado report inside them.

Dauphin County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10100%0
Severe thunderstorm warnings312132%1283%21 min
Flash flood warnings110%1100%25 min

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS State College, PA: tornado warnings13377%580%22 min
NWS State College, PA: severe thunderstorm warnings1668648%18280%26 min
NWS State College, PA: flash flood warnings382339%4393%64 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 5, 3:10 AM ESTWinter Storm WatchCTP19 hr
Jan 5, 10:11 PM ESTIce Storm WarningCTP39 hr
Jan 6, 5:17 PM ESTMesoscale DiscussionSPC4 hr
Jan 7, 12:10 AM ESTMesoscale DiscussionSPC4 hr
Jan 8, 3:30 PM ESTWinter Storm WatchCTP23 hr
Jan 9, 2:32 PM ESTWinter Storm WarningCTP30 hr
Jan 9, 2:32 PM ESTWinter Weather AdvisoryCTP37 hr
Jan 26, 3:30 AM ESTWinter Storm WatchCTP32 hr
Jan 27, 11:40 AM ESTWinter Storm WarningCTP31 hr
Jan 28, 12:31 AM ESTMesoscale DiscussionSPC5 hr
Jan 28, 7:53 AM ESTMesoscale DiscussionSPC5 hr
Feb 10, 3:31 PM ESTHigh Wind WatchCTP24 hr
Feb 11, 3:09 PM ESTHigh Wind WarningCTP28 hr
Feb 11, 3:09 PM ESTWind AdvisoryCTP32 hr
Feb 11, 8:00 PM ESTMesoscale DiscussionSPC60 min
Feb 11, 8:19 PM ESTSevere Thunderstorm WatchSPC3 hr
Feb 11, 10:14 PM ESTMesoscale DiscussionSPC61 min
Mar 1, 11:31 AM ESTWinter Weather AdvisoryCTP24 hr
Mar 8, 3:29 PM EDTWind AdvisoryCTP24 hr
Mar 10, 3:48 PM EDTWind AdvisoryCTP28 hr
Mar 23, 4:48 AM EDTRed Flag WarningCTP15 hr
Mar 27, 3:55 AM EDTDense Fog AdvisoryCTP6 hr
Apr 3, 3:04 AM EDTHigh Wind WatchCTP9 hr
Apr 3, 11:47 AM EDTWind AdvisoryCTP28 hr
Apr 28, 10:43 AM EDTRed Flag WarningCTP9 hr
May 4, 1:57 PM EDTAreal Flood AdvisoryCTP4 hr
May 5, 3:11 PM EDTFlood WatchCTP36 hr
May 7, 1:17 AM EDTAreal Flood AdvisoryCTP3 hr
May 14, 6:04 PM EDTSpecial Weather StatementCTP26 min
May 14, 6:56 PM EDTSpecial Weather StatementCTP34 min
May 15, 2:39 AM EDTDense Fog AdvisoryCTP5 hr
May 16, 12:05 PM EDTMesoscale DiscussionSPC55 min
May 16, 1:00 PM EDTSevere Thunderstorm WatchSPC7 hr
May 16, 3:55 PM EDTMesoscale DiscussionSPC65 min
May 16, 6:29 PM EDTMesoscale DiscussionSPC2 hr
May 16, 7:11 PM EDTSevere Thunderstorm WarningCTP64 min
May 16, 7:32 PM EDTSevere Thunderstorm WarningCTP58 min
May 16, 7:38 PM EDTSevere Thunderstorm WarningCTP52 min
May 16, 8:45 PM EDTAreal Flood AdvisoryCTP2 hr
May 17, 3:20 AM EDTFrost AdvisoryCTP30 hr
May 18, 3:28 PM EDTFrost AdvisoryCTP17 hr
May 23, 12:49 PM EDTMesoscale DiscussionSPC56 min
May 24, 7:11 PM EDTMesoscale DiscussionSPC64 min
May 28, 8:02 PM EDTAreal Flood AdvisoryCTP3 hr
May 28, 11:02 PM EDTAreal Flood AdvisoryCTP3 hr
May 29, 12:35 AM EDTAreal Flood AdvisoryCTP3 hr
May 29, 1:58 AM EDTAreal Flood AdvisoryCTP3 hr
May 29, 1:14 PM EDTSpecial Weather StatementCTP91 min
Jun 2, 3:38 AM EDTSpecial Weather StatementCTP67 min
Jun 2, 1:20 PM EDTSevere Thunderstorm WarningCTP55 min
Jun 9, 4:40 AM EDTSpecial Weather StatementCTP65 min
Jun 9, 5:09 AM EDTSevere Thunderstorm WarningCTP66 min
Jun 9, 1:19 PM EDTSevere Thunderstorm WarningCTP41 min
Jun 9, 1:31 PM EDTSevere Thunderstorm WatchSPC6 hr
Jun 9, 1:54 PM EDTSevere Thunderstorm WarningCTP66 min
Jun 9, 3:34 PM EDTSevere Thunderstorm WarningCTP41 min
Jun 9, 3:40 PM EDTMesoscale DiscussionSPC65 min
Jun 9, 4:17 PM EDTSpecial Weather StatementCTP28 min
Jun 10, 1:57 PM EDTMesoscale DiscussionSPC93 min
Jun 10, 3:01 PM EDTSpecial Weather StatementCTP59 min
Jun 10, 3:44 PM EDTSpecial Weather StatementCTP31 min
Jun 10, 4:20 PM EDTSpecial Weather StatementCTP25 min
Jun 10, 4:49 PM EDTSevere Thunderstorm WarningCTP56 min
Jun 10, 9:40 PM EDTAreal Flood AdvisoryCTP3 hr
Jun 10, 9:55 PM EDTFlash Flood WarningCTP4 hr
Jun 11, 4:04 AM EDTFlash Flood WatchCTP23 hr
Jun 11, 10:01 PM EDTMesoscale DiscussionSPC59 min
Jun 20, 7:15 AM EDTAreal Flood AdvisoryCTP3 hr
Jun 26, 2:19 PM EDTMesoscale DiscussionSPC56 min
Jun 26, 2:42 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 26, 6:42 PM EDTSevere Thunderstorm WarningCTP51 min
Jun 26, 7:33 PM EDTMesoscale DiscussionSPC57 min
Jun 30, 12:21 PM EDTSpecial Weather StatementCTP69 min
Jun 30, 12:27 PM EDTSevere Thunderstorm WarningCTP78 min
Jun 30, 1:14 PM EDTSevere Thunderstorm WarningCTP76 min
Jul 1, 12:03 PM EDTMesoscale DiscussionSPC87 min
Jul 2, 6:41 PM EDTSpecial Weather StatementCTP49 min
Jul 11, 3:52 PM EDTSpecial Weather StatementCTP53 min
Jul 11, 7:05 PM EDTSevere Thunderstorm WarningCTP40 min
Jul 11, 7:44 PM EDTSpecial Weather StatementCTP61 min
Jul 11, 8:38 PM EDTAreal Flood AdvisoryCTP3 hr
Jul 11, 9:06 PM EDTSevere Thunderstorm WarningCTP54 min
Jul 22, 4:37 PM EDTSpecial Weather StatementCTP38 min
Jul 22, 9:02 PM EDTAreal Flood AdvisoryCTP3 hr
Jul 23, 10:09 AM EDTAreal Flood AdvisoryCTP3 hr
Jul 23, 5:12 PM EDTSpecial Weather StatementCTP63 min
Jul 23, 7:25 PM EDTSevere Thunderstorm WarningCTP65 min
Jul 23, 7:35 PM EDTAreal Flood AdvisoryCTP3 hr
Jul 23, 8:16 PM EDTSpecial Weather StatementCTP59 min
Jul 24, 2:20 PM EDTMesoscale DiscussionSPC115 min
Jul 24, 3:20 PM EDTSpecial Weather StatementCTP40 min
Jul 24, 3:34 PM EDTMesoscale DiscussionSPC86 min
Jul 24, 4:16 PM EDTSevere Thunderstorm WarningCTP59 min
Jul 25, 6:36 AM EDTDense Fog AdvisoryCTP3 hr
Jul 25, 3:05 PM EDTMesoscale DiscussionSPC55 min
Jul 25, 3:50 PM EDTSevere Thunderstorm WatchSPC5 hr
Jul 25, 7:43 PM EDTMesoscale DiscussionSPC62 min
Jul 26, 3:40 AM EDTFlash Flood WatchCTP16 hr
Jul 26, 3:14 PM EDTMesoscale DiscussionSPC2 hr
Jul 26, 3:51 PM EDTSevere Thunderstorm WatchSPC7 hr
Jul 29, 2:44 PM EDTSpecial Weather StatementCTP31 min
Jul 29, 3:03 PM EDTSevere Thunderstorm WarningCTP27 min
Jul 29, 5:05 PM EDTMesoscale DiscussionSPC55 min
Jul 29, 7:23 PM EDTSevere Thunderstorm WarningCTP97 min
Jul 31, 10:20 AM EDTMesoscale DiscussionSPC85 min
Aug 1, 4:05 AM EDTDense Fog AdvisoryCTP5 hr
Aug 1, 6:15 PM EDTAreal Flood AdvisoryCTP79 min
Aug 2, 12:36 AM EDTAreal Flood AdvisoryCTP3 hr
Aug 2, 5:08 AM EDTFlash Flood WatchCTP10 hr
Aug 2, 8:19 AM EDTAreal Flood AdvisoryCTP3 hr
Aug 2, 8:29 AM EDTSevere Thunderstorm WarningCTP61 min
Aug 9, 2:45 PM EDTMesoscale DiscussionSPC60 min
Aug 9, 3:09 PM EDTHeat AdvisoryCTP28 hr
Aug 9, 3:18 PM EDTSevere Thunderstorm WatchSPC5 hr
Aug 9, 4:25 PM EDTSevere Thunderstorm WarningCTP65 min
Aug 9, 5:11 PM EDTSevere Thunderstorm WarningCTP49 min
Aug 9, 7:11 PM EDTMesoscale DiscussionSPC2 hr
Aug 10, 5:09 PM EDTSevere Thunderstorm WatchSPC5 hr
Aug 10, 8:15 PM EDTMesoscale DiscussionSPC2 hr
Aug 11, 9:53 PM EDTSpecial Weather StatementCTP22 min
Aug 11, 10:16 PM EDTSpecial Weather StatementCTP29 min
Aug 12, 12:36 PM EDTMesoscale DiscussionSPC84 min
Aug 12, 6:39 PM EDTAreal Flood AdvisoryCTP3 hr
Aug 12, 7:47 PM EDTAreal Flood AdvisoryCTP3 hr
Aug 13, 4:33 AM EDTFlash Flood WatchCTP15 hr
Aug 14, 4:04 AM EDTDense Fog AdvisoryCTP6 hr
Aug 15, 6:30 AM EDTDense Fog AdvisoryCTP4 hr
Aug 18, 4:50 PM EDTSevere Thunderstorm WarningCTP55 min
Aug 18, 4:57 PM EDTSevere Thunderstorm WarningCTP78 min
Aug 18, 5:19 PM EDTSpecial Weather StatementCTP56 min
Aug 18, 5:35 PM EDTSevere Thunderstorm WarningCTP70 min
Aug 19, 1:21 PM EDTMesoscale DiscussionSPC84 min
Aug 19, 5:23 PM EDTSpecial Weather StatementCTP37 min
Aug 19, 5:33 PM EDTSevere Thunderstorm WarningCTP57 min
Aug 19, 6:31 PM EDTSevere Thunderstorm WarningCTP59 min
Aug 19, 6:49 PM EDTAreal Flood AdvisoryCTP3 hr
Aug 20, 1:43 PM EDTSpecial Weather StatementCTP62 min
Aug 20, 2:40 PM EDTSevere Thunderstorm WarningCTP50 min
Aug 20, 3:04 PM EDTTornado WarningCTP26 min
Aug 20, 3:15 PM EDTSevere Thunderstorm WarningCTP60 min
Aug 20, 3:16 PM EDTSpecial Weather StatementCTP59 min
Aug 21, 11:28 AM EDTSevere Thunderstorm WatchSPC7 hr
Aug 21, 11:32 AM EDTSevere Thunderstorm WarningCTP58 min
Aug 21, 12:06 PM EDTSevere Thunderstorm WarningCTP54 min
Aug 21, 12:15 PM EDTSevere Thunderstorm WarningCTP75 min
Aug 21, 12:21 PM EDTAreal Flood AdvisoryCTP114 min
Aug 29, 5:03 PM EDTSpecial Weather StatementCTP57 min
Sep 11, 12:05 PM EDTAreal Flood AdvisoryCTP4 hr
Sep 23, 8:49 PM EDTSpecial Weather StatementCTP26 min
Oct 6, 2:59 PM EDTWind AdvisoryCTP29 hr
Oct 13, 3:28 AM EDTFrost AdvisoryCTP30 hr
Oct 18, 11:16 AM EDTFreeze WatchCTP3 hr
Oct 18, 2:26 PM EDTFreeze WarningCTP19 hr
Oct 19, 2:30 PM EDTFrost AdvisoryCTP18 hr
Oct 24, 9:50 AM EDTSpecial Weather StatementCTP25 min
Oct 24, 2:55 PM EDTAreal Flood AdvisoryCTP3 hr
Oct 24, 3:28 PM EDTAreal Flood AdvisoryCTP3 hr
Nov 26, 3:07 AM ESTDense Fog AdvisoryCTP6 hr
Dec 3, 3:58 AM ESTSpecial Weather StatementCTP47 min
Dec 5, 4:27 AM ESTWinter Weather AdvisoryCTP14 hr
Dec 8, 6:12 AM ESTWinter Weather AdvisoryCTP26 hr
Dec 9, 3:38 AM ESTWind AdvisoryCTP26 hr
Dec 12, 3:17 PM ESTFreezing Rain AdvisoryCTP25 hr
Dec 17, 10:08 PM ESTWinter Storm WatchCTP17 hr
Dec 18, 2:38 PM ESTWinter Storm WarningCTP32 hr
Dec 19, 6:57 AM ESTMesoscale DiscussionSPC6 hr
Dec 19, 12:27 PM ESTMesoscale DiscussionSPC6 hr
Dec 24, 2:05 PM ESTWinter Weather AdvisoryCTP29 hr
Dec 26, 8:56 AM ESTAreal Flood AdvisoryCTP6 hr
Dec 28, 2:33 PM ESTWind AdvisoryCTP28 hr
Dec 30, 2:45 PM ESTWinter Weather AdvisoryCTP19 hr
Dec 31, 6:40 PM ESTWinter Weather AdvisoryCTP6 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 archive20082010

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.