Alert archive / Wyoming / Big Horn County

Weather alerts in Big Horn County, Wyoming, 2017

108 weather alerts in 2017, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Big Horn County and its neighbors

Each county as a circle sized by its count in 2017. Tap one for its archive.

Alerts
108
Warnings
30
Watches
11
Advisories
27
Busiest month
June37 alerts
Busiest day
June 12, 20177 alerts

Over time

By month

Warning verification

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

2 of 2 tornado warnings covering Big Horn County in 2017 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 2 minutes after it went out.

Big Horn County, 2017

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings220%1100%2 min
Severe thunderstorm warnings8275%30%
Flash flood warnings00

Each office's whole area, 2017

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Riverton, WY: tornado warnings9367%757%20 min
NWS Riverton, WY: severe thunderstorm warnings50786%3027%18 min
NWS Riverton, WY: flash flood warnings4175%250%66 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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 1, 3:04 PM MSTWinter Weather AdvisoryRIW22 hr
Jan 5, 1:18 PM MSTWind Chill WarningRIW21 hr
Jan 7, 3:46 PM MSTWinter Storm WarningRIW4 days
Jan 9, 1:34 PM MSTWinter Storm WatchRIW21 hr
Jan 10, 10:35 AM MSTWinter Weather AdvisoryRIW35 hr
Jan 30, 3:16 PM MSTWinter Weather AdvisoryRIW3 days
Feb 11, 4:35 AM MSTAreal Flood WarningRIW3 days
Feb 14, 1:18 PM MSTAreal Flood WarningRIW48 hr
Feb 16, 1:01 PM MSTAreal Flood AdvisoryRIW72 hr
Feb 19, 12:19 PM MSTAreal Flood AdvisoryRIW24 hr
Feb 20, 8:11 AM MSTAreal Flood WarningRIW48 hr
Feb 20, 8:21 AM MSTAreal Flood WarningRIW48 hr
Feb 21, 1:34 PM MSTAreal Flood WarningRIW68 hr
Feb 24, 9:41 AM MSTAreal Flood AdvisoryRIW48 hr
Mar 22, 12:45 AM MDTWinter Weather AdvisoryRIW45 hr
Mar 25, 2:00 AM MDTWinter Weather AdvisoryRIW28 hr
Mar 27, 2:10 AM MDTWinter Weather AdvisoryRIW36 hr
Mar 30, 12:38 PM MDTWinter Weather AdvisoryRIW33 hr
Apr 2, 12:13 PM MDTWinter Weather AdvisoryRIW18 hr
Apr 7, 1:48 PM MDTWinter Weather AdvisoryRIW58 hr
Apr 18, 2:10 PM MDTWinter Weather AdvisoryRIW23 hr
Apr 19, 3:34 PM MDTWinter Storm WatchRIW8 hr
Apr 19, 11:07 PM MDTWinter Storm WarningRIW52 hr
Apr 23, 10:01 PM MDTWinter Weather AdvisoryRIW43 hr
Apr 25, 9:25 PM MDTWinter Weather AdvisoryRIW3 days
Apr 26, 2:34 PM MDTSpecial Weather StatementRIW26 min
Apr 26, 2:57 PM MDTWinter Storm WatchRIW11 hr
May 6, 2:22 PM MDTSpecial Weather StatementRIW23 min
May 7, 5:35 PM MDTMesoscale DiscussionSPC2 hr
May 7, 5:58 PM MDTSpecial Weather StatementRIW62 min
May 7, 6:31 PM MDTSpecial Weather StatementRIW44 min
May 16, 12:56 AM MDTWinter Storm WatchRIW23 hr
May 16, 9:13 AM MDTFlood WatchRIW54 hr
May 17, 12:23 AM MDTWinter Storm WarningRIW54 hr
May 25, 8:34 PM MDTWinter Weather AdvisoryRIW28 hr
Jun 2, 7:51 AM MDTAreal Flood WarningRIW24 hr
Jun 3, 7:36 AM MDTAreal Flood WarningRIW24 hr
Jun 4, 7:32 AM MDTAreal Flood WarningRIW6 days
Jun 5, 9:15 AM MDTAreal Flood AdvisoryRIW6 days
Jun 5, 1:27 PM MDTSpecial Weather StatementRIW33 min
Jun 5, 1:58 PM MDTSpecial Weather StatementRIW32 min
Jun 5, 2:14 PM MDTSevere Thunderstorm WarningRIW46 min
Jun 5, 3:08 PM MDTSpecial Weather StatementRIW37 min
Jun 5, 4:34 PM MDTSpecial Weather StatementRIW26 min
Jun 8, 7:41 AM MDTAreal Flood WarningRIW4 days
Jun 12, 2:17 PM MDTMesoscale DiscussionSPC88 min
Jun 12, 2:45 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 12, 3:27 PM MDTSevere Thunderstorm WarningRIW33 min
Jun 12, 3:55 PM MDTSpecial Weather StatementRIW35 min
Jun 12, 4:14 PM MDTSevere Thunderstorm WarningRIW31 min
Jun 12, 5:15 PM MDTSpecial Weather StatementBYZ30 min
Jun 12, 5:40 PM MDTTornado WarningRIW35 min
Jun 12, 6:00 PM MDTMesoscale DiscussionSPC90 min
Jun 12, 6:02 PM MDTSevere Thunderstorm WarningRIW19 min
Jun 12, 6:19 PM MDTTornado Warning Tornado observedRIW26 min
Jun 12, 6:56 PM MDTSevere Thunderstorm WarningRIW34 min
Jun 12, 7:34 PM MDTSevere Thunderstorm WarningRIW19 min
Jun 12, 8:13 PM MDTSpecial Weather StatementRIW32 min
Jun 12, 8:21 PM MDTSpecial Weather StatementRIW24 min
Jun 22, 10:21 AM MDTAreal Flood WarningRIW48 hr
Jun 27, 12:57 PM MDTSpecial Weather StatementRIW33 min
Jun 27, 1:19 PM MDTSevere Thunderstorm WarningRIW41 min
Jun 27, 1:21 PM MDTMesoscale DiscussionSPC84 min
Jun 27, 2:14 PM MDTSevere Thunderstorm WarningRIW46 min
Jun 28, 12:39 PM MDTMesoscale DiscussionSPC3 hr
Jun 28, 1:38 PM MDTSpecial Weather StatementRIW22 min
Jun 28, 2:01 PM MDTSpecial Weather StatementRIW29 min
Jun 28, 2:22 PM MDTSpecial Weather StatementRIW23 min
Jun 28, 5:08 PM MDTSpecial Weather StatementRIW67 min
Jun 28, 5:36 PM MDTSpecial Weather StatementRIW39 min
Jun 28, 5:41 PM MDTSpecial Weather StatementRIW49 min
Jun 29, 5:41 PM MDTSpecial Weather StatementRIW34 min
Jul 3, 8:07 PM MDTSpecial Weather StatementRIW38 min
Jul 5, 3:23 PM MDTSpecial Weather StatementRIW37 min
Jul 5, 4:40 PM MDTSpecial Weather StatementRIW50 min
Jul 5, 5:11 PM MDTSpecial Weather StatementRIW49 min
Jul 5, 5:44 PM MDTSpecial Weather StatementRIW46 min
Jul 6, 4:19 PM MDTSpecial Weather StatementRIW26 min
Jul 10, 7:54 PM MDTSpecial Weather StatementRIW36 min
Jul 16, 4:00 PM MDTSpecial Weather StatementRIW45 min
Jul 16, 4:53 PM MDTSpecial Weather StatementRIW37 min
Jul 16, 5:37 PM MDTSpecial Weather StatementRIW38 min
Jul 20, 2:18 PM MDTMesoscale DiscussionSPC2 hr
Aug 4, 7:15 PM MDTSpecial Weather StatementRIW30 min
Aug 11, 4:12 PM MDTSpecial Weather StatementRIW33 min
Aug 30, 3:26 PM MDTSpecial Weather StatementRIW34 min
Sep 1, 2:29 PM MDTFire Weather WatchBYZ24 hr
Sep 2, 2:50 PM MDTRed Flag WarningBYZ54 hr
Sep 13, 3:21 PM MDTWinter Storm WatchRIW24 hr
Sep 13, 7:09 PM MDTSpecial Weather StatementRIW36 min
Sep 14, 3:35 PM MDTWinter Storm WarningRIW43 hr
Sep 15, 10:34 PM MDTFreeze WatchRIW16 hr
Sep 16, 2:33 PM MDTFreeze WarningRIW18 hr
Sep 23, 2:17 PM MDTWinter Weather AdvisoryRIW34 hr
Oct 3, 1:15 PM MDTFreeze WarningRIW20 hr
Oct 25, 9:39 AM MDTHigh Wind WatchRIW3 hr
Oct 25, 12:38 PM MDTHigh Wind WarningRIW23 hr
Oct 31, 2:27 AM MDTWinter Storm WatchRIW25 hr
Oct 31, 3:00 PM MDTWinter Storm WarningRIW46 hr
Nov 1, 3:45 AM MDTWinter Weather AdvisoryRIW34 hr
Nov 5, 12:48 PM MSTWinter Weather AdvisoryRIW28 hr
Nov 5, 8:44 PM MSTDense Fog AdvisoryRIW11 hr
Dec 2, 1:39 PM MSTWinter Weather AdvisoryRIW45 hr
Dec 15, 12:55 PM MSTWinter Weather AdvisoryRIW37 hr
Dec 21, 3:32 PM MSTWinter Weather AdvisoryRIW51 hr
Dec 28, 12:17 PM MSTWinter Weather AdvisoryRIW48 hr
Dec 30, 12:35 PM MSTWind AdvisoryRIW16 min
Dec 30, 12:55 PM MSTWind Chill AdvisoryRIW19 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 archive20162018

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.