Alert archive / Montana / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Montana, 2018

334 severe thunderstorm warnings in 2018. 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 2018. Tap one for its archive.

Severe Thunderstorm Warnings: 334
Busiest month: June126 severe thunderstorm warnings
Busiest day: July 10, 201825 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.

171 of 334 severe thunderstorm warnings covering Montana in 2018 had a qualifying storm report inside them; 327 of 449 hail, wind and damage reports fell inside a warning, on average 25 minutes after it went out.

Montana, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Severe thunderstorm warnings	334	171	49%	449	73%	25 min

Each office's whole area, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Great Falls, MT: severe thunderstorm warnings	51	16	69%	67	45%	21 min
NWS Billings, MT: severe thunderstorm warnings	176	84	52%	213	73%	23 min
NWS Missoula, MT: severe thunderstorm warnings	11	9	18%	17	76%	18 min
NWS Glasgow, MT: severe thunderstorm warnings	108	65	40%	166	83%	28 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 29, 3:52 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River	53 min
Apr 29, 4:29 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River, Rosebud	41 min
Apr 29, 5:20 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	40 min
Apr 29, 6:05 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie	55 min
May 6, 6:40 PM MDT	Severe Thunderstorm Warning	MSO	Missoula	35 min
May 7, 2:04 PM MDT	Severe Thunderstorm Warning	BYZ	Treasure, Yellowstone	56 min
May 7, 3:00 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Treasure, Yellowstone	60 min
May 8, 6:49 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	26 min
May 9, 5:33 PM MDT	Severe Thunderstorm Warning	BYZ	Stillwater	27 min
May 9, 6:01 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater	29 min
May 10, 4:35 PM MDT	Severe Thunderstorm Warning	TFX	Hill	40 min
May 10, 5:12 PM MDT	Severe Thunderstorm Warning	TFX	Hill	48 min
May 10, 6:00 PM MDT	Severe Thunderstorm Warning	TFX	Hill	15 min
May 16, 3:35 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Hill	25 min
May 16, 3:59 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Hill	24 min
May 16, 7:48 PM MDT	Severe Thunderstorm Warning	BYZ	Fallon	57 min
May 17, 3:13 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	29 min
May 17, 3:15 PM MDT	Severe Thunderstorm Warning	GGW	Valley	30 min
May 17, 4:25 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	50 min
May 17, 5:10 PM MDT	Severe Thunderstorm Warning	GGW	Valley	50 min
May 17, 5:18 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	19 min
May 17, 5:49 PM MDT	Severe Thunderstorm Warning	GGW	Valley	41 min
May 17, 5:51 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River	24 min
May 17, 6:31 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	29 min
May 17, 7:03 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	38 min
May 17, 7:30 PM MDT	Severe Thunderstorm Warning	GGW	McCone	60 min
May 17, 8:29 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone	61 min
May 17, 8:43 PM MDT	Severe Thunderstorm Warning	GGW	McCone	43 min
May 21, 6:57 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Musselshell	33 min
May 22, 4:37 PM MDT	Severe Thunderstorm Warning	BYZ	Sweet Grass	38 min
May 22, 6:07 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	38 min
May 22, 6:18 PM MDT	Severe Thunderstorm Warning	BYZ	Stillwater	43 min
May 22, 7:49 PM MDT	Severe Thunderstorm Warning	BYZ	Stillwater	41 min
May 22, 8:51 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon	54 min
May 23, 10:25 AM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt, Sheridan	50 min
May 23, 3:45 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud	60 min
May 23, 3:49 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	56 min
May 23, 4:03 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud	57 min
May 23, 4:12 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	48 min
May 23, 4:29 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	61 min
May 23, 4:42 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	63 min
May 23, 4:48 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone	57 min
May 23, 5:18 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	57 min
May 23, 5:41 PM MDT	Severe Thunderstorm Warning	GGW	McCone	64 min
May 23, 5:45 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	60 min
May 23, 6:12 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud, Treasure, Yellowstone	63 min
May 23, 6:14 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	61 min
May 23, 6:18 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	57 min
May 23, 6:37 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud	53 min
May 23, 6:38 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie	37 min
May 23, 6:42 PM MDT	Severe Thunderstorm Warning	GGW	McCone	33 min
May 23, 6:44 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	61 min
May 23, 6:55 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie	50 min
May 23, 7:00 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	37 min
May 23, 7:16 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River	59 min
May 23, 7:18 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland	57 min
May 23, 8:02 PM MDT	Severe Thunderstorm Warning	GGW	Richland	43 min
May 23, 8:17 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Wibaux	29 min
May 26, 4:34 PM MDT	Severe Thunderstorm Warning	TFX	Beaverhead	20 min
May 26, 5:54 PM MDT	Severe Thunderstorm Warning	TFX	Jefferson	36 min
May 26, 5:55 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	65 min
May 26, 6:17 PM MDT	Severe Thunderstorm Warning	TFX	Jefferson, Madison	28 min
May 26, 6:35 PM MDT	Severe Thunderstorm Warning	TFX	Broadwater, Jefferson	25 min
May 26, 6:46 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	42 min
May 26, 6:46 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone	59 min
May 26, 6:52 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	53 min
May 26, 7:07 PM MDT	Severe Thunderstorm Warning	BYZ	Wheatland	15 min
May 26, 7:29 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Sweet Grass, Wheatland	61 min
May 26, 7:42 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	63 min
May 26, 8:00 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Stillwater, Wheatland	60 min
May 26, 8:38 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Richland	67 min
May 26, 9:14 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland	61 min
May 26, 9:44 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone	61 min
May 26, 11:02 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie, Richland, Wibaux	58 min
May 27, 12:52 AM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	23 min
May 30, 3:20 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	40 min
May 30, 7:52 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum	53 min
May 30, 10:08 PM MDT	Severe Thunderstorm Warning	GGW	Valley	52 min
May 30, 11:07 PM MDT	Severe Thunderstorm Warning	GGW	Richland	38 min
May 31, 12:52 PM MDT	Severe Thunderstorm Warning	MSO	Ravalli	38 min
May 31, 1:20 PM MDT	Severe Thunderstorm Warning	MSO	Missoula	40 min
May 31, 1:24 PM MDT	Severe Thunderstorm Warning	MSO	Ravalli	36 min
May 31, 2:19 PM MDT	Severe Thunderstorm Warning	MSO	Missoula	26 min
May 31, 2:33 PM MDT	Severe Thunderstorm Warning	TFX	Gallatin	13 min
May 31, 2:38 PM MDT	Severe Thunderstorm Warning	BYZ	Park, Sweet Grass	52 min
May 31, 2:47 PM MDT	Severe Thunderstorm Warning	MSO	Granite	43 min
May 31, 3:11 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Wheatland	34 min
May 31, 3:27 PM MDT	Severe Thunderstorm Warning	BYZ	Park, Sweet Grass	48 min
May 31, 3:44 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Wheatland	46 min
May 31, 4:16 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater	43 min
May 31, 4:27 PM MDT	Severe Thunderstorm Warning	BYZ	Sweet Grass	48 min
May 31, 4:28 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Musselshell	62 min
May 31, 4:39 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Lewis and Clark	36 min
May 31, 5:11 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Sweet Grass	37 min
May 31, 5:20 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	55 min
May 31, 6:14 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	61 min
May 31, 6:20 PM MDT	Severe Thunderstorm Warning	TFX	Beaverhead, Gallatin, Madison	40 min
May 31, 6:21 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	54 min
May 31, 6:59 PM MDT	Severe Thunderstorm Warning	TFX	Gallatin	14 min
May 31, 7:01 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	42 min
May 31, 7:03 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Musselshell	42 min
May 31, 7:10 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell, Rosebud	65 min
May 31, 7:27 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	46 min
May 31, 8:41 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell, Rosebud	64 min
May 31, 8:51 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer	54 min
May 31, 9:55 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	50 min
Jun 1, 10:28 AM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	47 min
Jun 1, 11:14 AM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud, Treasure	61 min
Jun 1, 12:08 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud	67 min
Jun 1, 12:53 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	67 min
Jun 1, 1:01 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Rosebud	44 min
Jun 1, 1:37 PM MDT	Severe Thunderstorm Warning	GGW	McCone, Prairie	53 min
Jun 1, 2:15 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie	60 min
Jun 1, 3:27 PM MDT	Severe Thunderstorm Warning	GGW	Richland	48 min
Jun 1, 4:03 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt, Sheridan	57 min
Jun 4, 4:38 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum, Phillips, Valley	34 min
Jun 4, 4:42 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	33 min
Jun 4, 4:55 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Musselshell	35 min
Jun 4, 4:57 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	33 min
Jun 4, 5:28 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	32 min
Jun 4, 5:57 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	33 min
Jun 4, 6:09 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	36 min
Jun 4, 7:02 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell, Rosebud, Treasure, Yellowstone	34 min
Jun 4, 7:33 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Judith Basin	27 min
Jun 4, 7:56 PM MDT	Severe Thunderstorm Warning	TFX	Fergus, Judith Basin	34 min
Jun 4, 8:56 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum, Phillips	44 min
Jun 5, 5:59 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	46 min
Jun 6, 6:56 PM MDT	Severe Thunderstorm Warning	TFX	Fergus, Judith Basin	34 min
Jun 6, 6:57 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River, Rosebud	63 min
Jun 6, 8:04 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	56 min
Jun 6, 11:04 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie, Wibaux	26 min
Jun 7, 9:59 AM MDT	Severe Thunderstorm Warning	TFX	Fergus	46 min
Jun 7, 10:16 AM MDT	Severe Thunderstorm Warning	GGW	Petroleum	44 min
Jun 7, 4:09 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon	51 min
Jun 7, 4:28 PM MDT	Severe Thunderstorm Warning	TFX	Liberty, Toole	32 min
Jun 7, 4:53 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Treasure	52 min
Jun 7, 4:57 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	63 min
Jun 7, 4:58 PM MDT	Severe Thunderstorm Warning	TFX	Liberty, Toole	32 min
Jun 7, 5:07 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	23 min
Jun 7, 5:27 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Treasure, Yellowstone	48 min
Jun 7, 5:28 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	47 min
Jun 7, 5:38 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	37 min
Jun 7, 5:54 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud	66 min
Jun 7, 6:14 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River, Rosebud	61 min
Jun 7, 6:19 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	56 min
Jun 7, 6:26 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	34 min
Jun 7, 6:41 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Rosebud	49 min
Jun 7, 7:00 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	60 min
Jun 7, 7:12 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie, Richland	63 min
Jun 7, 7:33 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	42 min
Jun 7, 7:48 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Richland, Roosevelt	27 min
Jun 7, 8:05 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie, Richland	43 min
Jun 7, 8:08 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Richland, Roosevelt	67 min
Jun 7, 8:12 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	63 min
Jun 7, 8:43 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	62 min
Jun 7, 8:57 PM MDT	Severe Thunderstorm Warning	GGW	McCone, Richland, Roosevelt	36 min
Jun 7, 9:03 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Richland, Roosevelt, Sheridan	46 min
Jun 7, 9:32 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	35 min
Jun 7, 9:38 PM MDT	Severe Thunderstorm Warning	GGW	Sheridan	40 min
Jun 8, 5:50 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	22 min
Jun 8, 7:13 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	47 min
Jun 8, 7:59 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	46 min
Jun 8, 8:44 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	46 min
Jun 9, 2:37 PM MDT	Severe Thunderstorm Warning	TFX	Lewis and Clark, Pondera, Teton	23 min
Jun 9, 3:27 PM MDT	Severe Thunderstorm Warning	MSO	Granite, Powell	33 min
Jun 9, 5:27 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	63 min
Jun 9, 6:35 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	40 min
Jun 9, 7:30 PM MDT	Severe Thunderstorm Warning	TFX	Fergus, Judith Basin	30 min
Jun 9, 8:15 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	30 min
Jun 9, 10:47 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	43 min
Jun 14, 8:30 AM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	45 min
Jun 14, 9:46 AM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	14 min
Jun 15, 5:49 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River, Rosebud	56 min
Jun 16, 4:39 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater	36 min
Jun 16, 5:10 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon	32 min
Jun 19, 3:56 PM MDT	Severe Thunderstorm Warning	BYZ	Treasure	49 min
Jun 21, 4:17 PM MDT	Severe Thunderstorm Warning	TFX	Fergus, Judith Basin	43 min
Jun 21, 4:56 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	64 min
Jun 21, 5:42 PM MDT	Severe Thunderstorm Warning	BYZ	Musselshell	28 min
Jun 25, 7:04 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Chouteau, Teton	26 min
Jun 25, 7:17 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Chouteau, Judith Basin, Teton	28 min
Jun 25, 8:22 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	23 min
Jun 25, 8:42 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	33 min
Jun 25, 8:49 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Liberty, Pondera, Teton	26 min
Jun 26, 4:51 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Stillwater, Yellowstone	54 min
Jun 26, 10:40 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	35 min
Jun 28, 2:56 PM MDT	Severe Thunderstorm Warning	TFX	Judith Basin, Meagher	34 min
Jun 28, 3:55 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	20 min
Jun 28, 3:59 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum	47 min
Jun 28, 4:08 PM MDT	Severe Thunderstorm Warning	TFX	Fergus, Judith Basin	37 min
Jun 28, 4:09 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	66 min
Jun 28, 4:11 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum	64 min
Jun 28, 4:28 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum	20 min
Jun 28, 5:03 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	27 min
Jun 28, 5:13 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Powder River	62 min
Jun 28, 5:25 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	29 min
Jun 28, 5:30 PM MDT	Severe Thunderstorm Warning	GGW	McCone	60 min
Jun 28, 6:09 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Roosevelt, Valley	66 min
Jun 28, 6:14 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	61 min
Jun 28, 6:15 PM MDT	Severe Thunderstorm Warning	BYZ	Sweet Grass	30 min
Jun 28, 6:30 PM MDT	Severe Thunderstorm Warning	BYZ	Park	30 min
Jun 28, 6:31 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Garfield, McCone, Prairie	59 min
Jun 28, 6:35 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River, Rosebud	55 min
Jun 28, 6:48 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River, Rosebud	57 min
Jun 28, 6:52 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	53 min
Jun 28, 6:54 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Stillwater, Sweet Grass	36 min
Jun 28, 6:54 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland	66 min
Jun 28, 7:05 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Richland, Roosevelt	55 min
Jun 28, 7:06 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Fallon	39 min
Jun 28, 7:11 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	64 min
Jun 28, 7:29 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River	61 min
Jun 28, 7:33 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie	57 min
Jun 28, 7:42 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt	48 min
Jun 28, 7:44 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River, Rosebud	61 min
Jun 28, 7:44 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland, Wibaux	61 min
Jun 28, 8:25 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Powder River	65 min
Jun 28, 8:29 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	61 min
Jun 28, 8:53 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Treasure	33 min
Jun 28, 9:26 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Fallon, Powder River	79 min
Jun 28, 10:18 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River, Rosebud	57 min
Jun 28, 10:41 PM MDT	Severe Thunderstorm Warning	BYZ	Powder River	34 min
Jul 2, 6:22 PM MDT	Severe Thunderstorm Warning	BYZ	Stillwater, Sweet Grass	38 min
Jul 2, 6:57 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Yellowstone	63 min
Jul 2, 7:25 PM MDT	Severe Thunderstorm Warning	BYZ	Treasure, Yellowstone	65 min
Jul 2, 7:55 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Stillwater, Yellowstone	65 min
Jul 2, 8:28 PM MDT	Severe Thunderstorm Warning	BYZ	Treasure	47 min
Jul 2, 8:44 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Yellowstone	61 min
Jul 2, 8:49 PM MDT	Severe Thunderstorm Warning	BYZ	Rosebud, Treasure	56 min
Jul 2, 9:33 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	42 min
Jul 2, 9:39 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Rosebud	51 min
Jul 2, 9:45 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Rosebud	60 min
Jul 2, 10:17 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	43 min
Jul 2, 10:23 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Powder River, Rosebud	52 min
Jul 2, 10:46 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer	44 min
Jul 2, 10:53 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	50 min
Jul 2, 11:15 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Powder River	45 min
Jul 2, 11:24 PM MDT	Severe Thunderstorm Warning	BYZ	Custer, Fallon	66 min
Jul 3, 12:02 AM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Fallon	43 min
Jul 3, 12:46 AM MDT	Severe Thunderstorm Warning	BYZ	Carter, Fallon	29 min
Jul 3, 7:54 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	51 min
Jul 3, 7:57 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie	63 min
Jul 3, 8:06 PM MDT	Severe Thunderstorm Warning	GGW	McCone, Roosevelt, Valley	54 min
Jul 3, 8:37 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland, Wibaux	53 min
Jul 3, 8:43 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Garfield, McCone, Roosevelt, Valley	62 min
Jul 3, 9:23 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Wibaux	37 min
Jul 7, 7:26 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Powder River	49 min
Jul 7, 8:11 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	64 min
Jul 9, 6:06 PM MDT	Severe Thunderstorm Warning	GGW	Sheridan	54 min
Jul 9, 6:56 PM MDT	Severe Thunderstorm Warning	GGW	Sheridan	64 min
Jul 9, 7:29 PM MDT	Severe Thunderstorm Warning	TFX	Judith Basin	46 min
Jul 9, 8:08 PM MDT	Severe Thunderstorm Warning	GGW	Daniels	67 min
Jul 9, 8:19 PM MDT	Severe Thunderstorm Warning	GGW	Sheridan	56 min
Jul 9, 8:52 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	53 min
Jul 9, 8:59 PM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	46 min
Jul 9, 9:11 PM MDT	Severe Thunderstorm Warning	GGW	Sheridan	20 min
Jul 9, 9:16 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt	59 min
Jul 9, 9:33 PM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	27 min
Jul 9, 9:43 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	14 min
Jul 9, 10:03 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt	57 min
Jul 9, 10:07 PM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	23 min
Jul 9, 10:18 PM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	42 min
Jul 9, 10:54 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt, Sheridan	51 min
Jul 10, 2:12 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus, Judith Basin	48 min
Jul 10, 3:05 PM MDT	Severe Thunderstorm Warning	BYZ	Golden Valley, Wheatland	35 min
Jul 10, 3:12 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Chouteau, Fergus	48 min
Jul 10, 3:27 PM MDT	Severe Thunderstorm Warning	TFX	Gallatin, Meagher	33 min
Jul 10, 4:46 PM MDT	Severe Thunderstorm Warning	GGW	Phillips	59 min
Jul 10, 4:54 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum, Phillips	66 min
Jul 10, 4:57 PM MDT	Severe Thunderstorm Warning	GGW	Phillips, Valley	63 min
Jul 10, 5:34 PM MDT	Severe Thunderstorm Warning	GGW	Phillips, Valley	56 min
Jul 10, 5:48 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Phillips, Valley	27 min
Jul 10, 5:54 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Phillips, Valley	66 min
Jul 10, 6:09 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Valley	51 min
Jul 10, 6:28 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Garfield, McCone, Roosevelt, Sheridan, Valley	47 min
Jul 10, 6:49 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	41 min
Jul 10, 7:11 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, McCone, Richland, Roosevelt, Sheridan, Valley	64 min
Jul 10, 7:48 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, McCone, Richland, Roosevelt, Sheridan	57 min
Jul 10, 8:40 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt, Sheridan	33 min
Jul 17, 2:46 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Powder River	44 min
Jul 17, 3:58 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Powder River	62 min
Jul 21, 12:04 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Valley	56 min
Jul 21, 12:54 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Valley	66 min
Jul 21, 1:19 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	56 min
Jul 21, 1:28 PM MDT	Severe Thunderstorm Warning	GGW	Daniels	62 min
Jul 21, 2:17 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	58 min
Jul 21, 3:11 PM MDT	Severe Thunderstorm Warning	GGW	Roosevelt, Sheridan	79 min
Jul 21, 3:33 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	45 min
Jul 21, 3:49 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Powder River	41 min
Jul 21, 4:20 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt	40 min
Jul 21, 4:26 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	34 min
Jul 21, 4:34 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	56 min
Jul 21, 4:42 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	35 min
Jul 21, 4:53 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt	67 min
Jul 21, 5:25 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	22 min
Jul 21, 8:16 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	29 min
Jul 25, 7:46 PM MDT	Severe Thunderstorm Warning	TFX	Glacier, Pondera, Teton, Toole	59 min
Jul 25, 8:44 PM MDT	Severe Thunderstorm Warning	TFX	Teton	61 min
Jul 25, 9:45 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Teton	60 min
Jul 26, 3:21 PM MDT	Severe Thunderstorm Warning	TFX	Glacier	54 min
Jul 26, 4:34 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Lewis and Clark	22 min
Jul 26, 4:50 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Sweet Grass	55 min
Jul 26, 5:33 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Stillwater	57 min
Jul 27, 2:44 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	31 min
Jul 27, 3:45 PM MDT	Severe Thunderstorm Warning	BYZ	Stillwater, Yellowstone	30 min
Jul 27, 3:52 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Sweet Grass	38 min
Jul 27, 4:08 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	52 min
Jul 27, 4:27 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater	63 min
Jul 27, 4:39 PM MDT	Severe Thunderstorm Warning	MSO	Granite, Powell	36 min
Jul 27, 4:54 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Yellowstone	66 min
Jul 27, 5:12 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon	48 min
Jul 27, 5:22 PM MDT	Severe Thunderstorm Warning	MSO	Deer Lodge, Powell	53 min
Jul 27, 5:57 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Rosebud	48 min
Jul 27, 6:43 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	62 min
Jul 27, 7:47 PM MDT	Severe Thunderstorm Warning	TFX	Gallatin	28 min
Jul 28, 5:02 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Sweet Grass	43 min
Jul 28, 5:43 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater	62 min
Jul 28, 7:29 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	31 min
Jul 28, 7:58 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	47 min
Aug 2, 2:32 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Yellowstone	28 min
Aug 2, 2:57 PM MDT	Severe Thunderstorm Warning	BYZ	Carbon, Stillwater, Yellowstone	48 min
Aug 2, 5:58 PM MDT	Severe Thunderstorm Warning	BYZ	Park	50 min
Aug 3, 1:40 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Chouteau	35 min
Aug 3, 4:51 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carbon, Yellowstone	39 min
Aug 3, 5:27 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Custer, Powder River, Rosebud, Treasure	63 min
Aug 3, 6:28 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 1 more	62 min
Aug 3, 6:41 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Powder River	49 min
Aug 3, 7:02 PM MDT	Severe Thunderstorm Warning	BYZ	Custer	28 min
Aug 3, 7:23 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, McCone, Prairie, Wibaux	52 min
Aug 3, 7:28 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Custer, Fallon, Powder River	92 min
Aug 3, 9:00 PM MDT	Severe Thunderstorm Warning	BYZ	Carter, Fallon	30 min
Aug 5, 6:35 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt	40 min
Aug 20, 3:53 PM MDT	Severe Thunderstorm Warning	TFX	Beaverhead	37 min
Aug 23, 6:14 AM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie, Wibaux	61 min
Sep 18, 11:17 PM MDT	Severe Thunderstorm Warning	BYZ	Carter	58 min

By county

Every county with at least one alert. A county page lists each alert that covered it.

10 more counties

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record The radar archive 2017 2019

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.