Alert archive / Montana / Powell County

Weather alerts in Powell County, Montana, 2010

127 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Powell County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Alerts
127
Warnings
31
Watches
19
Advisories
52
Busiest month
August19 alerts
Busiest day
July 1, 20108 alerts

Over time

By month

Warning verification

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

Powell County, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings10550%580%31 min
Flash flood warnings00

Each office's whole area, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Missoula, MT: tornado warnings010%
NWS Missoula, MT: severe thunderstorm warnings532357%6755%19 min
NWS Missoula, MT: flash flood warnings70100%20%

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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Dec 31, 8:55 PM MSTWinter Weather AdvisoryMSO13 hr
Jan 1, 5:14 AM MSTWinter Weather AdvisoryMSO33 hr
Jan 4, 3:37 AM MSTWinter Storm WarningMSO47 hr
Jan 4, 1:49 PM MSTWinter Weather AdvisoryMSO39 hr
Jan 6, 8:54 AM MSTWind Chill AdvisoryMSO3 hr
Jan 7, 6:44 AM MSTWind Chill AdvisoryMSO6 hr
Jan 7, 8:22 PM MSTWind Chill AdvisoryMSO17 hr
Jan 12, 3:39 AM MSTFreezing Rain AdvisoryMSO5 hr
Jan 12, 1:54 PM MSTWinter Weather AdvisoryMSO17 hr
Jan 13, 6:59 AM MSTDense Fog AdvisoryMSO8 hr
Jan 14, 3:29 AM MSTDense Fog AdvisoryMSO5 hr
Jan 14, 2:21 PM MSTWind AdvisoryMSO30 hr
Jan 16, 8:16 PM MSTDense Fog AdvisoryMSO18 hr
Jan 22, 3:47 AM MSTWinter Storm WatchMSO11 hr
Jan 22, 3:47 AM MSTWinter Weather AdvisoryMSO43 hr
Jan 22, 7:46 AM MSTWinter Storm WarningMSO37 hr
Jan 24, 4:21 AM MSTWinter Weather AdvisoryMSO5 hr
Feb 8, 8:42 AM MSTFreezing Fog AdvisoryMSO3 hr
Feb 8, 6:46 PM MSTDense Fog AdvisoryMSO15 hr
Mar 8, 2:23 PM MSTWinter Weather AdvisoryMSO21 hr
Mar 9, 5:24 PM MSTWinter Weather AdvisoryMSO10 hr
Mar 12, 4:14 AM MSTWinter Weather AdvisoryMSO31 hr
Mar 29, 3:32 AM MDTWind AdvisoryMSO14 hr
Apr 1, 3:03 PM MDTWind AdvisoryMSO31 hr
Apr 5, 2:33 PM MDTWinter Weather AdvisoryMSO19 hr
Apr 7, 2:22 PM MDTHigh Wind WarningMSO31 hr
Apr 7, 2:22 PM MDTWind AdvisoryMSO31 hr
Apr 7, 2:39 PM MDTRed Flag WarningTFX53 hr
Apr 12, 2:50 PM MDTWinter Storm WarningMSO43 hr
Apr 12, 2:50 PM MDTWinter Weather AdvisoryMSO27 hr
Apr 28, 3:32 AM MDTWinter Storm WatchMSO11 hr
Apr 28, 3:32 AM MDTWinter Storm WarningMSO50 hr
Apr 28, 2:59 PM MDTWinter Weather AdvisoryMSO39 hr
May 1, 2:42 PM MDTHigh Wind WatchMSO31 hr
May 2, 11:13 AM MDTHigh Wind WarningMSO41 hr
May 4, 4:01 AM MDTWinter Weather AdvisoryMSO14 hr
May 4, 2:43 PM MDTWinter Storm WatchMSO14 hr
May 5, 4:21 AM MDTWinter Storm WarningMSO28 hr
May 17, 4:11 PM MDTSpecial Weather StatementMSO64 min
May 17, 5:23 PM MDTSpecial Weather StatementMSO97 min
May 21, 2:24 PM MDTWinter Weather AdvisoryMSO40 hr
May 22, 9:00 PM MDTWinter Storm WarningMSO9 hr
May 23, 4:07 AM MDTWinter Storm WatchMSO10 hr
May 23, 2:13 PM MDTWinter Storm WarningMSO26 hr
Jun 15, 2:27 PM MDTFlood WatchMSO53 hr
Jun 20, 1:20 AM MDTFlood WatchMSO37 hr
Jun 20, 2:52 PM MDTSevere Thunderstorm WarningMSO38 min
Jun 20, 3:53 PM MDTSpecial Weather StatementMSO37 min
Jun 29, 1:41 PM MDTMesoscale DiscussionSPC64 min
Jun 29, 2:26 PM MDTSpecial Weather StatementMSO49 min
Jun 29, 2:31 PM MDTSevere Thunderstorm WatchSPC10 hr
Jun 29, 3:34 PM MDTSevere Thunderstorm WarningMSO26 min
Jun 29, 3:37 PM MDTSevere Thunderstorm WarningMSO27 min
Jun 29, 5:46 PM MDTMesoscale DiscussionSPC89 min
Jun 29, 5:59 PM MDTSevere Thunderstorm WarningMSO43 min
Jun 29, 9:44 PM MDTMesoscale DiscussionSPC61 min
Jun 29, 10:10 PM MDTSevere Thunderstorm WarningMSO35 min
Jun 29, 11:46 PM MDTSevere Thunderstorm WarningMSO24 min
Jun 30, 1:58 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 30, 8:11 PM MDTSpecial Weather StatementMSO49 min
Jun 30, 8:25 PM MDTSevere Thunderstorm WarningMSO50 min
Jun 30, 9:14 PM MDTSevere Thunderstorm WarningMSO31 min
Jul 1, 12:45 PM MDTMesoscale DiscussionSPC60 min
Jul 1, 1:37 PM MDTSevere Thunderstorm WatchSPC8 hr
Jul 1, 2:30 PM MDTSpecial Weather StatementMSO45 min
Jul 1, 3:13 PM MDTSevere Thunderstorm WarningMSO16 min
Jul 1, 4:57 PM MDTMesoscale DiscussionSPC63 min
Jul 10, 5:26 PM MDTSpecial Weather StatementMSO34 min
Jul 11, 2:56 PM MDTWind AdvisoryMSO30 hr
Jul 31, 12:53 PM MDTMesoscale DiscussionSPC67 min
Jul 31, 1:19 PM MDTSevere Thunderstorm WatchSPC9 hr
Jul 31, 2:58 PM MDTSpecial Weather StatementMSO32 min
Jul 31, 5:02 PM MDTMesoscale DiscussionSPC118 min
Jul 31, 9:12 PM MDTSpecial Weather StatementMSO33 min
Aug 5, 7:26 PM MDTSpecial Weather StatementMSO49 min
Aug 5, 8:21 PM MDTSpecial Weather StatementMSO39 min
Aug 6, 2:09 PM MDTFlash Flood WatchMSO8 hr
Aug 6, 3:03 PM MDTSevere Thunderstorm WatchSPC8 hr
Aug 6, 6:36 PM MDTMesoscale DiscussionSPC84 min
Aug 9, 1:32 PM MDTFlash Flood WatchMSO8 hr
Aug 10, 1:40 PM MDTMesoscale DiscussionSPC2 hr
Aug 10, 5:27 PM MDTSpecial Weather StatementMSO63 min
Aug 12, 12:26 PM MDTWinter Weather AdvisoryMSO22 hr
Aug 20, 12:00 PM MDTRed Flag WarningMSO33 hr
Aug 20, 2:46 PM MDTRed Flag WarningTFX30 hr
Aug 24, 1:57 PM MDTFire Weather WatchMSO24 hr
Aug 24, 2:22 PM MDTFire Weather WatchTFX24 hr
Aug 25, 2:14 PM MDTRed Flag WarningMSO34 hr
Aug 25, 2:46 PM MDTRed Flag WarningTFX33 hr
Aug 26, 11:22 AM MDTWind AdvisoryMSO12 hr
Aug 26, 8:37 PM MDTSevere Thunderstorm WarningMSO23 min
Aug 31, 2:41 PM MDTWinter Weather AdvisoryMSO27 hr
Sep 4, 1:11 PM MDTMesoscale DiscussionSPC64 min
Sep 4, 1:54 PM MDTSpecial Weather StatementMSO51 min
Sep 4, 3:48 PM MDTSpecial Weather StatementMSO27 min
Sep 13, 7:59 PM MDTAreal Flood AdvisoryMSO92 min
Sep 13, 8:03 PM MDTSpecial Weather StatementMSO42 min
Oct 23, 1:35 PM MDTWinter Weather AdvisoryMSO70 hr
Oct 30, 7:44 AM MDTDense Fog AdvisoryMSO3 hr
Nov 7, 2:17 PM MSTWinter Weather AdvisoryMSO27 hr
Nov 11, 2:45 PM MSTWinter Weather AdvisoryMSO21 hr
Nov 14, 2:24 PM MSTWinter Weather AdvisoryMSO69 hr
Nov 15, 11:38 AM MSTHigh Wind WarningMSO20 hr
Nov 17, 2:55 PM MSTWinter Weather AdvisoryMSO28 hr
Nov 19, 3:06 AM MSTWind Chill AdvisoryMSO56 hr
Nov 19, 3:06 AM MSTWinter Weather AdvisoryMSO44 hr
Nov 20, 3:37 AM MSTWind Chill AdvisoryMSO31 hr
Nov 20, 12:13 PM MSTWinter Weather AdvisoryMSO8 hr
Nov 21, 3:05 AM MSTWinter Storm WarningMSO58 hr
Nov 22, 2:27 PM MSTBlizzard WarningMSO23 hr
Nov 23, 1:16 PM MSTWind Chill WarningMSO9 hr
Nov 24, 10:07 AM MSTWind Chill WarningMSO10 hr
Nov 25, 8:02 AM MSTWinter Weather AdvisoryMSO3 days
Dec 1, 2:47 PM MSTWinter Weather AdvisoryMSO38 hr
Dec 8, 3:30 AM MSTWinter Storm WatchMSO35 hr
Dec 8, 10:26 AM MSTWinter Weather AdvisoryMSO4 hr
Dec 8, 2:40 PM MSTWinter Storm WarningMSO56 hr
Dec 8, 7:44 PM MSTWinter Weather AdvisoryMSO46 hr
Dec 9, 2:46 PM MSTWind AdvisoryMSO17 hr
Dec 10, 2:54 PM MSTWinter Weather AdvisoryMSO46 hr
Dec 14, 4:37 AM MSTWinter Weather AdvisoryMSO30 hr
Dec 14, 9:48 AM MSTHigh Wind WatchMSO5 hr
Dec 19, 3:52 AM MSTWinter Weather AdvisoryMSO33 hr
Dec 27, 3:49 AM MSTWinter Storm WatchMSO31 hr
Dec 27, 5:17 PM MSTWinter Storm WarningMSO60 hr
Dec 28, 10:43 AM MSTWinter Weather AdvisoryMSO46 hr
Dec 30, 3:49 AM MSTWind Chill AdvisoryMSO11 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 archive20092011

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.