Alert archive / Wyoming / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in Wyoming, 2009
223 severe thunderstorm warnings in 2009. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of severe thunderstorm warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Severe Thunderstorm Warnings
- 223
- Busiest month
- July99 severe thunderstorm warnings
- Busiest day
- June 14, 200918 severe thunderstorm warnings
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
100 of 223 severe thunderstorm warnings covering Wyoming in 2009 had a qualifying storm report inside them; 148 of 226 hail, wind and damage reports fell inside a warning, on average 25 minutes after it went out.
Wyoming, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 223 | 100 | 55% | 226 | 65% | 25 min |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Riverton, WY: severe thunderstorm warnings | 77 | 23 | 70% | 63 | 56% | 22 min |
| NWS Cheyenne, WY: severe thunderstorm warnings | 186 | 86 | 54% | 227 | 66% | 20 min |
| NWS Billings, MT: severe thunderstorm warnings | 85 | 28 | 67% | 63 | 60% | 23 min |
| NWS Salt Lake City, UT: severe thunderstorm warnings | 79 | 10 | 87% | 63 | 24% | 19 min |
| NWS Rapid City, SD: severe thunderstorm warnings | 262 | 172 | 34% | 345 | 79% | 27 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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 3:41 PM MDT | Severe Thunderstorm Warning | RIW | Sweetwater | 49 min |
| Apr 25, 4:27 PM MDT | Severe Thunderstorm Warning | RIW | Sweetwater | 48 min |
| Apr 25, 5:11 PM MDT | Severe Thunderstorm Warning | CYS | Carbon | 37 min |
| May 12, 1:51 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 39 min |
| May 12, 2:34 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 43 min |
| May 20, 3:55 PM MDT | Severe Thunderstorm Warning | CYS | Niobrara | 65 min |
| May 20, 3:59 PM MDT | Severe Thunderstorm Warning | CYS | Carbon | 32 min |
| May 22, 6:06 PM MDT | Severe Thunderstorm Warning | CYS | Niobrara | 39 min |
| May 30, 3:08 PM MDT | Severe Thunderstorm Warning | CYS | Platte | 24 min |
| May 30, 5:26 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 28 min |
| Jun 4, 4:12 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie, Platte | 48 min |
| Jun 4, 6:08 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 52 min |
| Jun 4, 6:56 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 42 min |
| Jun 5, 2:47 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 58 min |
| Jun 5, 3:06 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 54 min |
| Jun 5, 4:26 PM MDT | Severe Thunderstorm Warning | CYS | Niobrara | 26 min |
| Jun 5, 5:12 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs, Washakie | 29 min |
| Jun 5, 5:20 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Park | 40 min |
| Jun 5, 6:42 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn | 42 min |
| Jun 5, 8:41 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 49 min |
| Jun 5, 9:06 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 39 min |
| Jun 5, 9:30 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 35 min |
| Jun 7, 5:40 AM MDT | Severe Thunderstorm Warning | CYS | Laramie | 42 min |
| Jun 7, 1:19 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 22 min |
| Jun 9, 4:29 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 24 min |
| Jun 10, 2:47 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 33 min |
| Jun 10, 3:19 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 26 min |
| Jun 11, 2:17 PM MDT | Severe Thunderstorm Warning | CYS | Platte | 58 min |
| Jun 11, 4:44 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 61 min |
| Jun 13, 2:54 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 51 min |
| Jun 13, 3:22 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 38 min |
| Jun 13, 3:53 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 37 min |
| Jun 13, 4:23 PM MDT | Severe Thunderstorm Warning | CYS | Albany | 67 min |
| Jun 13, 4:26 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 49 min |
| Jun 13, 4:37 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 29 min |
| Jun 13, 5:02 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 58 min |
| Jun 13, 5:06 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 39 min |
| Jun 13, 5:15 PM MDT | Severe Thunderstorm Warning | RIW | Sweetwater | 30 min |
| Jun 13, 5:23 PM MDT | Severe Thunderstorm Warning | CYS | Converse, Niobrara, Platte | 45 min |
| Jun 13, 5:24 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 66 min |
| Jun 13, 5:27 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 29 min |
| Jun 13, 5:35 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 40 min |
| Jun 13, 5:41 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 64 min |
| Jun 13, 6:02 PM MDT | Severe Thunderstorm Warning | CYS | Converse, Niobrara | 58 min |
| Jun 13, 6:04 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 41 min |
| Jun 13, 6:06 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 54 min |
| Jun 13, 6:17 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 58 min |
| Jun 13, 6:38 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 23 min |
| Jun 13, 6:57 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 35 min |
| Jun 13, 7:07 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 38 min |
| Jun 13, 7:09 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 66 min |
| Jun 13, 7:18 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 42 min |
| Jun 13, 8:33 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 42 min |
| Jun 14, 1:00 PM MDT | Severe Thunderstorm Warning | CYS | Platte | 23 min |
| Jun 14, 2:15 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs | 45 min |
| Jun 14, 2:54 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs | 66 min |
| Jun 14, 3:38 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 25 min |
| Jun 14, 3:40 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 57 min |
| Jun 14, 4:12 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 35 min |
| Jun 14, 4:49 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 56 min |
| Jun 14, 5:32 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 58 min |
| Jun 14, 6:11 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 49 min |
| Jun 14, 8:21 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 39 min |
| Jun 15, 10:56 AM MDT | Severe Thunderstorm Warning | UNR | Campbell | 64 min |
| Jun 15, 12:55 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 65 min |
| Jun 15, 2:49 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 56 min |
| Jun 17, 2:16 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 35 min |
| Jun 17, 2:30 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 47 min |
| Jun 17, 4:43 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 36 min |
| Jun 20, 8:51 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 24 min |
| Jun 21, 6:33 PM MDT | Severe Thunderstorm Warning | SLC | Uinta | 31 min |
| Jun 22, 11:37 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 38 min |
| Jun 23, 3:39 PM MDT | Severe Thunderstorm Warning | CYS | Albany | 66 min |
| Jun 23, 4:58 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie, Platte | 62 min |
| Jun 23, 5:26 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 64 min |
| Jun 23, 5:43 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 62 min |
| Jun 30, 3:28 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 62 min |
| Jun 30, 5:12 PM MDT | Severe Thunderstorm Warning | RIW | Teton | 63 min |
| Jul 1, 6:05 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 55 min |
| Jul 1, 6:33 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 27 min |
| Jul 1, 6:36 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 54 min |
| Jul 1, 7:07 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 53 min |
| Jul 1, 8:47 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 58 min |
| Jul 2, 2:19 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs | 41 min |
| Jul 2, 3:05 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie | 40 min |
| Jul 2, 3:06 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 24 min |
| Jul 2, 3:23 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs | 37 min |
| Jul 2, 3:39 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 66 min |
| Jul 2, 3:44 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie, Platte | 41 min |
| Jul 2, 4:02 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie, Platte | 58 min |
| Jul 2, 4:34 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 56 min |
| Jul 2, 5:02 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 58 min |
| Jul 2, 6:01 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 59 min |
| Jul 2, 6:33 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Platte | 39 min |
| Jul 2, 7:19 PM MDT | Severe Thunderstorm Warning | CYS | Niobrara | 33 min |
| Jul 3, 6:01 PM MDT | Severe Thunderstorm Warning | RIW | Lincoln | 48 min |
| Jul 4, 3:34 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 41 min |
| Jul 4, 4:16 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 59 min |
| Jul 4, 5:13 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 77 min |
| Jul 4, 6:15 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 45 min |
| Jul 4, 6:59 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 46 min |
| Jul 5, 3:05 PM MDT | Severe Thunderstorm Warning | CYS | Laramie, Platte | 40 min |
| Jul 5, 3:34 PM MDT | Severe Thunderstorm Warning | CYS | Laramie, Platte | 30 min |
| Jul 6, 2:35 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 42 min |
| Jul 6, 3:45 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 60 min |
| Jul 6, 4:16 PM MDT | Severe Thunderstorm Warning | RIW | Washakie | 34 min |
| Jul 6, 5:59 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 46 min |
| Jul 6, 6:26 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 49 min |
| Jul 6, 6:32 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 73 min |
| Jul 6, 6:41 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 49 min |
| Jul 7, 6:08 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Converse, Platte | 52 min |
| Jul 7, 6:13 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 47 min |
| Jul 7, 7:17 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 23 min |
| Jul 7, 8:25 PM MDT | Severe Thunderstorm Warning | RIW | Johnson, Natrona | 50 min |
| Jul 8, 4:13 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 62 min |
| Jul 8, 4:22 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 53 min |
| Jul 8, 4:58 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 62 min |
| Jul 9, 8:36 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 54 min |
| Jul 9, 8:57 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Weston | 63 min |
| Jul 9, 9:18 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Weston | 57 min |
| Jul 9, 9:22 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 53 min |
| Jul 9, 10:08 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 67 min |
| Jul 10, 9:11 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 49 min |
| Jul 10, 9:15 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 45 min |
| Jul 11, 7:22 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 57 min |
| Jul 11, 7:41 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 64 min |
| Jul 11, 7:56 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 51 min |
| Jul 11, 8:10 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 65 min |
| Jul 12, 1:57 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 63 min |
| Jul 12, 2:42 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 63 min |
| Jul 12, 3:46 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 29 min |
| Jul 12, 3:50 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 55 min |
| Jul 12, 4:10 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 65 min |
| Jul 12, 4:17 PM MDT | Severe Thunderstorm Warning | CYS | Laramie, Platte | 32 min |
| Jul 12, 5:02 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Goshen, Platte | 58 min |
| Jul 12, 5:12 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 63 min |
| Jul 12, 5:56 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Platte | 42 min |
| Jul 12, 6:10 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Converse, Platte | 65 min |
| Jul 12, 7:13 PM MDT | Severe Thunderstorm Warning | CYS | Converse, Niobrara, Platte | 27 min |
| Jul 12, 7:19 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Johnson, Washakie | 41 min |
| Jul 13, 2:37 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 53 min |
| Jul 13, 2:57 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Park, Washakie | 35 min |
| Jul 13, 3:28 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 49 min |
| Jul 13, 3:36 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 54 min |
| Jul 13, 3:48 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Washakie | 42 min |
| Jul 13, 3:50 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 55 min |
| Jul 13, 4:04 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 56 min |
| Jul 13, 4:06 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 54 min |
| Jul 13, 4:16 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Johnson | 44 min |
| Jul 13, 4:40 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook, Weston | 65 min |
| Jul 13, 4:51 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 54 min |
| Jul 13, 5:36 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 84 min |
| Jul 13, 5:41 PM MDT | Severe Thunderstorm Warning | UNR | Crook, Weston | 64 min |
| Jul 13, 6:27 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 47 min |
| Jul 13, 6:45 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 75 min |
| Jul 16, 8:40 PM MDT | Severe Thunderstorm Warning | CYS | Albany | 26 min |
| Jul 16, 9:02 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie | 44 min |
| Jul 18, 1:35 AM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 42 min |
| Jul 20, 1:47 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 49 min |
| Jul 20, 5:21 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 39 min |
| Jul 20, 5:26 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 35 min |
| Jul 20, 5:58 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 51 min |
| Jul 22, 5:59 PM MDT | Severe Thunderstorm Warning | RIW | Sweetwater | 61 min |
| Jul 27, 1:26 PM MDT | Severe Thunderstorm Warning | RIW | Sweetwater | 64 min |
| Jul 27, 2:46 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 22 min |
| Jul 27, 2:58 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie | 47 min |
| Jul 27, 2:59 PM MDT | Severe Thunderstorm Warning | RIW | Fremont, Sweetwater | 61 min |
| Jul 27, 3:48 PM MDT | Severe Thunderstorm Warning | RIW | Fremont, Hot Springs, Natrona, Washakie | 42 min |
| Jul 27, 4:41 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 35 min |
| Jul 27, 5:08 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 67 min |
| Jul 27, 5:51 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 54 min |
| Jul 27, 5:53 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 37 min |
| Jul 28, 4:22 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 53 min |
| Jul 28, 5:07 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 53 min |
| Jul 28, 5:49 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 56 min |
| Jul 28, 6:40 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 48 min |
| Jul 28, 7:10 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 38 min |
| Aug 3, 1:29 PM MDT | Severe Thunderstorm Warning | RIW | Hot Springs, Park, Washakie | 61 min |
| Aug 4, 3:27 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 63 min |
| Aug 4, 3:56 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 64 min |
| Aug 4, 4:39 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 36 min |
| Aug 4, 5:00 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 15 min |
| Aug 4, 5:04 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook, Weston | 56 min |
| Aug 4, 5:54 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook, Weston | 66 min |
| Aug 4, 6:09 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Weston | 51 min |
| Aug 4, 6:58 PM MDT | Severe Thunderstorm Warning | UNR | Crook, Weston | 77 min |
| Aug 4, 7:00 PM MDT | Severe Thunderstorm Warning | CYS | Converse, Niobrara | 60 min |
| Aug 5, 7:56 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 49 min |
| Aug 5, 8:31 PM MDT | Severe Thunderstorm Warning | UNR | Crook, Weston | 33 min |
| Aug 6, 6:25 AM MDT | Severe Thunderstorm Warning | UNR | Crook | 34 min |
| Aug 6, 3:46 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 56 min |
| Aug 6, 4:24 PM MDT | Severe Thunderstorm Warning | RIW | Teton | 33 min |
| Aug 6, 5:02 PM MDT | Severe Thunderstorm Warning | RIW | Teton | 58 min |
| Aug 6, 5:18 PM MDT | Severe Thunderstorm Warning | RIW | Teton | 29 min |
| Aug 6, 5:25 PM MDT | Severe Thunderstorm Warning | RIW | Park | 50 min |
| Aug 7, 4:02 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Park | 58 min |
| Aug 7, 4:18 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Park | 57 min |
| Aug 7, 4:54 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 35 min |
| Aug 7, 5:33 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn | 27 min |
| Aug 7, 5:49 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 56 min |
| Aug 7, 6:44 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 46 min |
| Aug 7, 7:32 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 20 min |
| Aug 7, 10:17 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 58 min |
| Aug 7, 11:01 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 44 min |
| Aug 7, 11:54 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 66 min |
| Aug 8, 12:36 AM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 54 min |
| Aug 8, 1:18 AM MDT | Severe Thunderstorm Warning | RIW | Johnson | 42 min |
| Aug 8, 1:25 AM MDT | Severe Thunderstorm Warning | UNR | Crook | 25 min |
| Aug 8, 2:09 AM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook, Weston | 66 min |
| Aug 8, 2:18 AM MDT | Severe Thunderstorm Warning | RIW | Natrona | 42 min |
| Aug 8, 2:24 AM MDT | Severe Thunderstorm Warning | RIW | Fremont | 37 min |
| Aug 8, 2:34 AM MDT | Severe Thunderstorm Warning | RIW | Natrona | 26 min |
| Aug 8, 6:28 PM MDT | Severe Thunderstorm Warning | UNR | Crook | 52 min |
| Aug 8, 7:20 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 29 min |
| Aug 10, 4:38 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 52 min |
| Aug 14, 7:27 PM MDT | Severe Thunderstorm Warning | BYZ | Sheridan | 52 min |
| Aug 15, 3:28 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 50 min |
| Aug 15, 5:57 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 63 min |
| Aug 15, 7:07 PM MDT | Severe Thunderstorm Warning | RIW | Fremont | 53 min |
| Aug 23, 6:52 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 53 min |
| Aug 23, 7:10 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 50 min |
| Aug 25, 1:41 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Converse, Platte | 64 min |
| Sep 20, 6:29 PM MDT | Severe Thunderstorm Warning | RIW | Natrona | 46 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Goshen County38
- Laramie County32
- Crook County29
- Platte County27
- Campbell County25
- Fremont County22
- Weston County21
- Johnson County16
- Natrona County16
- Albany County12
- Sheridan County10
- Big Horn County9
- Converse County9
- Niobrara County8
- Hot Springs County7
- Washakie County7
- Sweetwater County6
- Park County6
- Teton County4
- Carbon County2
- Uinta County1
- Lincoln County1
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe 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.