Alert archive / Montana / Stillwater County

Weather alerts in Stillwater County, Montana, 2021

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

Stillwater County and its neighbors

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

Alerts
128
Warnings
29
Watches
20
Advisories
44
Busiest month
December23 alerts
Busiest day
July 7, 20214 alerts

Over time

By month

Warning verification

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

Stillwater County, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings220%10%
Flash flood warnings00

Each office's whole area, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Billings, MT: severe thunderstorm warnings512355%8442%18 min
NWS Billings, MT: flash flood warnings20100%0

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
Jan 1, 3:03 AM MSTWind AdvisoryBYZ63 hr
Jan 3, 2:30 PM MSTSpecial Weather StatementBYZ2 hr
Jan 7, 5:23 PM MSTWinter Weather AdvisoryBYZ16 hr
Jan 11, 3:04 AM MSTHigh Wind WatchBYZ34 hr
Jan 11, 11:45 AM MSTWind AdvisoryBYZ25 hr
Jan 12, 2:51 AM MSTHigh Wind WarningBYZ65 hr
Jan 12, 12:06 PM MSTWinter Storm WarningBYZ34 hr
Jan 18, 2:43 PM MSTHigh Wind WatchBYZ12 hr
Jan 19, 2:36 AM MSTWind AdvisoryBYZ35 hr
Jan 20, 2:06 PM MSTWinter Weather AdvisoryBYZ45 hr
Feb 2, 1:20 AM MSTWinter Weather AdvisoryBYZ43 hr
Feb 3, 2:50 PM MSTWinter Storm WatchBYZ37 hr
Feb 4, 9:28 AM MSTWinter Storm WarningBYZ3 days
Feb 6, 3:26 AM MSTWind Chill AdvisoryBYZ10 days
Feb 7, 3:48 AM MSTWinter Weather AdvisoryBYZ24 hr
Feb 14, 2:24 AM MSTWinter Weather AdvisoryBYZ48 hr
Feb 18, 1:24 AM MSTWind AdvisoryBYZ34 hr
Feb 19, 11:08 AM MSTHigh Wind WatchBYZ16 hr
Feb 20, 3:00 AM MSTHigh Wind WarningBYZ4 days
Feb 24, 3:01 AM MSTWind AdvisoryBYZ57 hr
Feb 27, 1:19 PM MSTSpecial Weather StatementBYZ41 min
Feb 27, 2:19 PM MSTSpecial Weather StatementBYZ41 min
Feb 27, 3:11 PM MSTSpecial Weather StatementBYZ34 min
Mar 19, 1:06 PM MDTWinter Storm WarningBYZ37 hr
Mar 19, 7:06 PM MDTWinter Weather AdvisoryBYZ31 hr
Mar 22, 2:30 AM MDTWinter Weather AdvisoryBYZ43 hr
Mar 24, 7:35 AM MDTSpecial Weather StatementBYZ115 min
Mar 24, 12:03 PM MDTWinter Weather AdvisoryBYZ63 hr
Mar 27, 3:15 AM MDTHigh Wind WatchBYZ23 hr
Mar 28, 2:27 AM MDTHigh Wind WarningBYZ40 hr
Mar 29, 5:52 AM MDTSpecial Weather StatementBYZ113 min
Apr 4, 1:43 PM MDTWinter Weather AdvisoryBYZ49 hr
Apr 14, 2:06 AM MDTWinter Weather AdvisoryBYZ58 hr
Apr 17, 2:09 AM MDTWinter Storm WatchBYZ13 hr
Apr 17, 3:31 PM MDTWinter Storm WarningBYZ45 hr
Apr 17, 3:31 PM MDTWinter Weather AdvisoryBYZ42 hr
Apr 22, 2:19 AM MDTWinter Weather AdvisoryBYZ32 hr
May 7, 2:25 PM MDTMesoscale DiscussionSPC2 hr
May 28, 3:55 PM MDTMesoscale DiscussionSPC2 hr
Jun 4, 1:59 PM MDTMesoscale DiscussionSPC2 hr
Jun 5, 2:27 PM MDTMesoscale DiscussionSPC2 hr
Jun 10, 1:47 PM MDTMesoscale DiscussionSPC88 min
Jun 10, 6:10 PM MDTSpecial Weather StatementBYZ95 min
Jun 10, 7:45 PM MDTSpecial Weather StatementBYZ2 hr
Jun 13, 2:34 PM MDTExcessive Heat WarningBYZ54 hr
Jun 14, 9:26 AM MDTRed Flag WarningBYZ43 hr
Jun 14, 2:27 PM MDTMesoscale DiscussionSPC2 hr
Jun 18, 2:46 AM MDTFire Weather WatchBYZ11 hr
Jun 18, 2:00 PM MDTRed Flag WarningBYZ31 hr
Jun 23, 4:33 PM MDTMesoscale DiscussionSPC117 min
Jun 29, 1:38 AM MDTExcessive Heat WatchBYZ36 hr
Jun 30, 1:34 PM MDTHeat AdvisoryBYZ4 days
Jul 4, 8:21 PM MDTSpecial Weather StatementBYZ39 min
Jul 6, 2:37 PM MDTMesoscale DiscussionSPC83 min
Jul 7, 2:03 PM MDTMesoscale DiscussionSPC117 min
Jul 7, 3:03 PM MDTSevere Thunderstorm WatchSPC8 hr
Jul 7, 5:48 PM MDTMesoscale DiscussionSPC117 min
Jul 7, 5:49 PM MDTSevere Thunderstorm WarningBYZ56 min
Jul 7, 6:35 PM MDTSevere Thunderstorm WarningBYZ55 min
Jul 9, 2:20 PM MDTMesoscale DiscussionSPC85 min
Jul 9, 2:39 PM MDTSpecial Weather StatementBYZ51 min
Jul 9, 3:18 PM MDTSpecial Weather StatementBYZ27 min
Jul 14, 12:51 PM MDTExcessive Heat WatchBYZ46 hr
Jul 16, 11:06 AM MDTExcessive Heat WarningBYZ6 days
Jul 16, 3:14 PM MDTHeat AdvisoryBYZ3 days
Jul 16, 3:50 PM MDTSpecial Weather StatementBYZ40 min
Jul 18, 3:10 PM MDTRed Flag WarningBYZ57 hr
Jul 21, 1:39 PM MDTFire Weather WatchBYZ24 hr
Jul 21, 4:01 PM MDTSpecial Weather StatementBYZ44 min
Jul 21, 4:39 PM MDTSpecial Weather StatementBYZ51 min
Jul 22, 1:40 PM MDTRed Flag WarningBYZ31 hr
Jul 24, 12:18 PM MDTExcessive Heat WatchBYZ25 hr
Jul 25, 1:39 PM MDTExcessive Heat WarningBYZ58 hr
Aug 7, 3:06 AM MDTFire Weather WatchBYZ11 hr
Aug 7, 2:26 PM MDTRed Flag WarningBYZ34 hr
Aug 8, 10:58 PM MDTSpecial Weather StatementBYZ32 min
Aug 9, 2:58 AM MDTFire Weather WatchBYZ10 hr
Aug 9, 12:55 PM MDTRed Flag WarningBYZ57 hr
Aug 14, 3:08 AM MDTFire Weather WatchBYZ11 hr
Aug 14, 2:07 PM MDTRed Flag WarningBYZ3 days
Aug 16, 2:49 PM MDTMesoscale DiscussionSPC116 min
Aug 17, 2:21 PM MDTMesoscale DiscussionSPC114 min
Sep 4, 2:20 PM MDTFire Weather WatchBYZ24 hr
Sep 5, 2:29 PM MDTRed Flag WarningBYZ30 hr
Sep 14, 1:04 PM MDTRed Flag WarningBYZ31 hr
Sep 16, 1:53 PM MDTRed Flag WarningBYZ55 hr
Sep 27, 1:50 AM MDTFire Weather WatchBYZ12 hr
Sep 27, 2:06 PM MDTRed Flag WarningBYZ31 hr
Sep 28, 9:27 PM MDTSpecial Weather StatementBYZ78 min
Oct 9, 1:08 PM MDTWinter Storm WatchBYZ38 hr
Oct 10, 2:47 PM MDTWinter Storm WarningBYZ3 days
Oct 11, 3:34 AM MDTWinter Weather AdvisoryBYZ47 hr
Oct 25, 1:31 PM MDTHigh Wind WatchBYZ36 hr
Oct 27, 1:53 AM MDTWind AdvisoryBYZ18 hr
Oct 29, 2:50 AM MDTWind AdvisoryBYZ19 hr
Oct 30, 11:51 PM MDTWinter Weather AdvisoryBYZ9 hr
Nov 12, 2:05 AM MSTWind AdvisoryBYZ32 hr
Nov 14, 2:15 AM MSTWind AdvisoryBYZ63 hr
Nov 15, 2:44 AM MSTHigh Wind WarningBYZ39 hr
Nov 20, 11:50 AM MSTWind AdvisoryBYZ61 hr
Nov 24, 12:16 AM MSTWind AdvisoryBYZ63 hr
Nov 24, 3:56 AM MSTSpecial Weather StatementBYZ4 hr
Nov 27, 2:39 AM MSTWind AdvisoryBYZ50 hr
Nov 29, 2:04 PM MSTHigh Wind WarningBYZ67 hr
Nov 29, 2:04 PM MSTWind AdvisoryBYZ41 hr
Dec 3, 1:53 PM MSTWind AdvisoryBYZ31 hr
Dec 4, 1:55 PM MSTWinter Weather AdvisoryBYZ22 hr
Dec 5, 5:45 AM MSTSpecial Weather StatementBYZ2 hr
Dec 5, 4:39 PM MSTSpecial Weather StatementBYZ3 hr
Dec 6, 1:18 AM MSTWinter Weather AdvisoryBYZ32 hr
Dec 7, 1:41 AM MSTWind AdvisoryBYZ40 hr
Dec 9, 2:14 PM MSTWind AdvisoryBYZ41 hr
Dec 10, 2:04 PM MSTHigh Wind WarningBYZ51 hr
Dec 13, 7:51 AM MSTWind AdvisoryBYZ31 hr
Dec 13, 2:37 PM MSTWinter Weather AdvisoryBYZ50 hr
Dec 17, 11:59 AM MSTWinter Weather AdvisoryBYZ27 hr
Dec 18, 2:40 PM MSTHigh Wind WarningBYZ25 hr
Dec 18, 2:41 PM MSTWinter Weather AdvisoryBYZ44 hr
Dec 20, 2:30 AM MSTWind AdvisoryBYZ4 days
Dec 21, 3:29 PM MSTWinter Storm WatchBYZ22 hr
Dec 22, 1:52 PM MSTWinter Storm WarningBYZ54 hr
Dec 26, 4:06 AM MSTWinter Weather AdvisoryBYZ17 hr
Dec 26, 4:59 AM MSTSpecial Weather StatementBYZ3 hr
Dec 26, 8:00 AM MSTSpecial Weather StatementBYZ90 min
Dec 26, 6:39 PM MSTWind Chill AdvisoryBYZ41 hr
Dec 27, 12:21 PM MSTSpecial Weather StatementBYZ69 min
Dec 30, 2:47 AM MSTWinter Weather AdvisoryBYZ32 hr
Dec 30, 12:30 PM MSTWinter Weather AdvisoryBYZ27 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.