Alert archive / Montana / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Montana, 2009

295 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
295
Busiest month
July151 severe thunderstorm warnings
Busiest day
July 6, 200933 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.

125 of 295 severe thunderstorm warnings covering Montana in 2009 had a qualifying storm report inside them; 194 of 304 hail, wind and damage reports fell inside a warning, on average 24 minutes after it went out.

Montana, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings29512558%30464%24 min

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Missoula, MT: severe thunderstorm warnings301357%3580%22 min
NWS Great Falls, MT: severe thunderstorm warnings873066%6853%21 min
NWS Billings, MT: severe thunderstorm warnings852867%6360%23 min
NWS Glasgow, MT: severe thunderstorm warnings1055845%15768%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.

IssuedProductOfficeCountiesLasted
May 5, 3:12 PM MDTSevere Thunderstorm WarningTFXFergus33 min
May 5, 3:54 PM MDTSevere Thunderstorm WarningGGWGarfield, Petroleum33 min
May 5, 4:56 PM MDTSevere Thunderstorm WarningGGWGarfield64 min
May 7, 3:55 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone, Valley34 min
May 7, 7:49 PM MDTSevere Thunderstorm WarningTFXChouteau, Hill35 min
May 8, 5:38 PM MDTSevere Thunderstorm WarningTFXChouteau52 min
May 10, 12:21 PM MDTSevere Thunderstorm WarningGGWDawson9 min
May 10, 12:42 PM MDTSevere Thunderstorm WarningGGWDawson33 min
May 10, 12:57 PM MDTSevere Thunderstorm WarningGGWPetroleum, Phillips48 min
May 10, 2:42 PM MDTSevere Thunderstorm WarningGGWRoosevelt23 min
May 12, 2:11 PM MDTSevere Thunderstorm WarningBYZCarter64 min
May 12, 2:56 PM MDTSevere Thunderstorm WarningBYZCarter34 min
May 12, 5:57 PM MDTSevere Thunderstorm WarningBYZBig Horn, Yellowstone38 min
May 14, 6:10 PM MDTSevere Thunderstorm WarningGGWMcCone, Roosevelt, Valley48 min
May 19, 4:10 PM MDTSevere Thunderstorm WarningGGWGarfield, Petroleum, Phillips47 min
May 19, 8:53 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt, Valley67 min
May 19, 9:04 PM MDTSevere Thunderstorm WarningGGWMcCone, Richland, Roosevelt, Valley56 min
May 19, 10:00 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan30 min
May 30, 3:15 PM MDTSevere Thunderstorm WarningMSOFlathead, Lake30 min
Jun 14, 4:47 PM MDTSevere Thunderstorm WarningBYZCarter58 min
Jun 15, 1:28 PM MDTSevere Thunderstorm WarningBYZTreasure, Yellowstone20 min
Jun 15, 4:00 PM MDTSevere Thunderstorm WarningBYZCarter30 min
Jun 20, 5:27 PM MDTSevere Thunderstorm WarningBYZSweet Grass22 min
Jun 20, 7:47 PM MDTSevere Thunderstorm WarningGGWMcCone58 min
Jun 20, 9:59 PM MDTSevere Thunderstorm WarningBYZRosebud31 min
Jun 20, 10:15 PM MDTSevere Thunderstorm WarningBYZBig Horn30 min
Jun 20, 10:44 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud31 min
Jun 25, 3:15 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Fergus45 min
Jun 25, 4:19 PM MDTSevere Thunderstorm WarningGGWPhillips41 min
Jun 25, 4:39 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Judith Basin24 min
Jun 25, 6:07 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone, Valley23 min
Jun 25, 6:31 PM MDTSevere Thunderstorm WarningGGWMcCone, Roosevelt, Valley29 min
Jun 29, 5:28 PM MDTSevere Thunderstorm WarningGGWDaniels, Sheridan62 min
Jun 29, 6:19 PM MDTSevere Thunderstorm WarningGGWDaniels, Sheridan56 min
Jun 30, 2:55 PM MDTSevere Thunderstorm WarningTFXBeaverhead, Madison65 min
Jun 30, 3:11 PM MDTSevere Thunderstorm WarningGGWRichland49 min
Jun 30, 3:34 PM MDTSevere Thunderstorm WarningBYZCarter49 min
Jun 30, 3:56 PM MDTSevere Thunderstorm WarningGGWDawson, Richland64 min
Jun 30, 3:59 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt61 min
Jun 30, 4:14 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Richland, Wibaux46 min
Jun 30, 4:37 PM MDTSevere Thunderstorm WarningTFXGallatin38 min
Jun 30, 5:06 PM MDTSevere Thunderstorm WarningGGWRichland24 min
Jun 30, 5:33 PM MDTSevere Thunderstorm WarningGGWWibaux51 min
Jun 30, 5:57 PM MDTSevere Thunderstorm WarningGGWWibaux63 min
Jun 30, 6:11 PM MDTSevere Thunderstorm WarningBYZFallon64 min
Jun 30, 6:32 PM MDTSevere Thunderstorm WarningBYZFallon58 min
Jun 30, 7:04 PM MDTSevere Thunderstorm WarningBYZCarter, Fallon86 min
Jun 30, 8:40 PM MDTSevere Thunderstorm WarningBYZCarter, Fallon33 min
Jul 1, 5:23 PM MDTSevere Thunderstorm WarningBYZCarter52 min
Jul 2, 11:18 AM MDTSevere Thunderstorm WarningBYZBig Horn57 min
Jul 2, 11:23 AM MDTSevere Thunderstorm WarningBYZRosebud43 min
Jul 2, 12:14 PM MDTSevere Thunderstorm WarningBYZBig Horn61 min
Jul 2, 1:04 PM MDTSevere Thunderstorm WarningBYZCuster, Rosebud30 min
Jul 2, 1:08 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud52 min
Jul 2, 1:49 PM MDTSevere Thunderstorm WarningBYZRosebud40 min
Jul 2, 2:52 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus53 min
Jul 2, 3:07 PM MDTSevere Thunderstorm WarningTFXBroadwater, Jefferson53 min
Jul 2, 3:11 PM MDTSevere Thunderstorm WarningTFXMeagher64 min
Jul 2, 3:46 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau59 min
Jul 2, 3:57 PM MDTSevere Thunderstorm WarningTFXBroadwater, Gallatin63 min
Jul 2, 4:13 PM MDTSevere Thunderstorm WarningTFXMeagher22 min
Jul 2, 4:16 PM MDTSevere Thunderstorm WarningBYZMusselshell59 min
Jul 2, 5:14 PM MDTSevere Thunderstorm WarningBYZMusselshell30 min
Jul 3, 4:17 PM MDTSevere Thunderstorm WarningBYZYellowstone17 min
Jul 3, 4:37 PM MDTSevere Thunderstorm WarningGGWDaniels53 min
Jul 3, 5:01 PM MDTSevere Thunderstorm WarningGGWPhillips, Valley59 min
Jul 3, 5:27 PM MDTSevere Thunderstorm WarningGGWDaniels63 min
Jul 3, 5:53 PM MDTSevere Thunderstorm WarningGGWValley67 min
Jul 3, 6:22 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt53 min
Jul 3, 6:56 PM MDTSevere Thunderstorm WarningGGWMcCone, Roosevelt, Valley64 min
Jul 3, 7:57 PM MDTSevere Thunderstorm WarningGGWMcCone, Richland, Roosevelt, Valley63 min
Jul 3, 8:04 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt56 min
Jul 3, 8:51 PM MDTSevere Thunderstorm WarningTFXBlaine40 min
Jul 4, 2:29 PM MDTSevere Thunderstorm WarningTFXLewis and Clark30 min
Jul 4, 4:06 PM MDTSevere Thunderstorm WarningTFXChouteau39 min
Jul 4, 4:23 PM MDTSevere Thunderstorm WarningTFXGlacier37 min
Jul 4, 4:35 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus40 min
Jul 4, 4:53 PM MDTSevere Thunderstorm WarningTFXChouteau37 min
Jul 4, 5:21 PM MDTSevere Thunderstorm WarningTFXGlacier, Pondera24 min
Jul 4, 5:29 PM MDTSevere Thunderstorm WarningTFXChouteau5 min
Jul 4, 5:35 PM MDTSevere Thunderstorm WarningTFXChouteau25 min
Jul 4, 5:46 PM MDTSevere Thunderstorm WarningTFXGlacier, Pondera29 min
Jul 4, 6:16 PM MDTSevere Thunderstorm WarningTFXPondera59 min
Jul 4, 7:01 PM MDTSevere Thunderstorm WarningBYZGolden Valley, Musselshell, Stillwater, Yellowstone39 min
Jul 5, 3:41 PM MDTSevere Thunderstorm WarningGGWDaniels, McCone, Richland, Roosevelt, Valley64 min
Jul 5, 4:43 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland62 min
Jul 5, 5:43 PM MDTSevere Thunderstorm WarningGGWDawson, Richland62 min
Jul 5, 6:33 PM MDTSevere Thunderstorm WarningGGWDawson, Wibaux57 min
Jul 5, 7:00 PM MDTSevere Thunderstorm WarningGGWDawson, Wibaux60 min
Jul 5, 7:37 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Wibaux53 min
Jul 5, 8:20 PM MDTSevere Thunderstorm WarningBYZFallon55 min
Jul 6, 12:56 PM MDTSevere Thunderstorm WarningMSORavalli49 min
Jul 6, 1:37 PM MDTSevere Thunderstorm WarningMSOPowell23 min
Jul 6, 1:45 PM MDTSevere Thunderstorm WarningMSODeer Lodge, Granite, Powell, Ravalli45 min
Jul 6, 2:06 PM MDTSevere Thunderstorm WarningTFXJefferson39 min
Jul 6, 2:07 PM MDTSevere Thunderstorm WarningMSOPowell38 min
Jul 6, 2:12 PM MDTSevere Thunderstorm WarningTFXLewis and Clark48 min
Jul 6, 2:29 PM MDTSevere Thunderstorm WarningMSOGranite, Powell46 min
Jul 6, 2:44 PM MDTSevere Thunderstorm WarningTFXLewis and Clark, Teton46 min
Jul 6, 2:49 PM MDTSevere Thunderstorm WarningTFXLewis and Clark41 min
Jul 6, 2:58 PM MDTSevere Thunderstorm WarningTFXLewis and Clark47 min
Jul 6, 3:03 PM MDTSevere Thunderstorm WarningMSOPowell27 min
Jul 6, 3:03 PM MDTSevere Thunderstorm WarningTFXMadison42 min
Jul 6, 3:06 PM MDTSevere Thunderstorm WarningTFXLewis and Clark, Teton54 min
Jul 6, 3:19 PM MDTSevere Thunderstorm WarningTFXCascade, Meagher41 min
Jul 6, 3:19 PM MDTSevere Thunderstorm WarningTFXBroadwater, Jefferson26 min
Jul 6, 3:33 PM MDTSevere Thunderstorm WarningTFXPondera, Teton42 min
Jul 6, 3:48 PM MDTSevere Thunderstorm WarningTFXBroadwater, Meagher17 min
Jul 6, 3:56 PM MDTSevere Thunderstorm WarningTFXCascade, Teton49 min
Jul 6, 3:58 PM MDTSevere Thunderstorm WarningTFXBroadwater, Meagher19 min
Jul 6, 4:09 PM MDTSevere Thunderstorm WarningTFXBroadwater, Cascade, Lewis and Clark, Meagher22 min
Jul 6, 4:15 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin45 min
Jul 6, 4:21 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus, Judith Basin39 min
Jul 6, 4:22 PM MDTSevere Thunderstorm WarningTFXChouteau, Judith Basin3 min
Jul 6, 4:24 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Pondera, Teton38 min
Jul 6, 4:38 PM MDTSevere Thunderstorm WarningTFXBroadwater, Gallatin, Judith Basin, Meagher52 min
Jul 6, 4:44 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau46 min
Jul 6, 5:24 PM MDTSevere Thunderstorm WarningTFXChouteau34 min
Jul 6, 5:43 PM MDTSevere Thunderstorm WarningBYZWheatland62 min
Jul 6, 5:54 PM MDTSevere Thunderstorm WarningTFXChouteau, Hill, Liberty51 min
Jul 6, 6:06 PM MDTSevere Thunderstorm WarningTFXFergus39 min
Jul 6, 7:40 PM MDTSevere Thunderstorm WarningGGWGarfield, Petroleum, Phillips, Valley65 min
Jul 6, 7:57 PM MDTSevere Thunderstorm WarningGGWPhillips63 min
Jul 6, 8:03 PM MDTSevere Thunderstorm WarningGGWGarfield57 min
Jul 6, 8:43 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone, Phillips, Valley62 min
Jul 6, 9:36 PM MDTSevere Thunderstorm WarningGGWDawson, Garfield, McCone, Prairie, Roosevelt, Valley54 min
Jul 6, 9:44 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt, Valley61 min
Jul 6, 10:28 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Prairie, Richland47 min
Jul 6, 10:43 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan62 min
Jul 6, 11:15 PM MDTSevere Thunderstorm WarningGGWDawson, Richland, Wibaux44 min
Jul 7, 7:13 PM MDTSevere Thunderstorm WarningBYZGolden Valley, Wheatland62 min
Jul 8, 6:52 AM MDTSevere Thunderstorm WarningTFXFergus38 min
Jul 8, 9:42 AM MDTSevere Thunderstorm WarningGGWGarfield, McCone63 min
Jul 8, 10:41 AM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland64 min
Jul 8, 11:45 AM MDTSevere Thunderstorm WarningGGWRichland60 min
Jul 8, 12:38 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt22 min
Jul 8, 3:40 PM MDTSevere Thunderstorm WarningBYZCarter65 min
Jul 8, 4:29 PM MDTSevere Thunderstorm WarningBYZCarter26 min
Jul 8, 5:22 PM MDTSevere Thunderstorm WarningBYZCarter19 min
Jul 8, 5:56 PM MDTSevere Thunderstorm WarningBYZCarter29 min
Jul 8, 5:59 PM MDTSevere Thunderstorm WarningGGWRichland, Wibaux16 min
Jul 8, 6:18 PM MDTSevere Thunderstorm WarningBYZCarter, Fallon17 min
Jul 8, 6:39 PM MDTSevere Thunderstorm WarningGGWDawson, Richland29 min
Jul 8, 6:50 PM MDTSevere Thunderstorm WarningBYZCuster, Fallon55 min
Jul 12, 2:45 PM MDTSevere Thunderstorm WarningTFXMadison25 min
Jul 12, 2:52 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark38 min
Jul 12, 3:30 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Lewis and Clark, Teton45 min
Jul 12, 3:30 PM MDTSevere Thunderstorm WarningTFXMadison32 min
Jul 12, 3:37 PM MDTSevere Thunderstorm WarningTFXGallatin38 min
Jul 12, 4:53 PM MDTSevere Thunderstorm WarningBYZPark, Sweet Grass25 min
Jul 12, 5:40 PM MDTSevere Thunderstorm WarningTFXMadison50 min
Jul 12, 6:09 PM MDTSevere Thunderstorm WarningTFXHill, Liberty42 min
Jul 12, 6:13 PM MDTSevere Thunderstorm WarningTFXGallatin37 min
Jul 12, 6:31 PM MDTSevere Thunderstorm WarningBYZBig Horn59 min
Jul 12, 7:07 PM MDTSevere Thunderstorm WarningBYZBig Horn53 min
Jul 12, 7:58 PM MDTSevere Thunderstorm WarningBYZBig Horn62 min
Jul 12, 9:18 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud28 min
Jul 13, 10:19 AM MDTSevere Thunderstorm WarningTFXBroadwater, Cascade, Lewis and Clark, Meagher41 min
Jul 13, 10:56 AM MDTSevere Thunderstorm WarningTFXCascade22 min
Jul 13, 11:25 AM MDTSevere Thunderstorm WarningTFXPondera, Teton50 min
Jul 13, 11:52 AM MDTSevere Thunderstorm WarningTFXPondera38 min
Jul 13, 12:21 PM MDTSevere Thunderstorm WarningTFXPondera, Toole39 min
Jul 13, 1:04 PM MDTSevere Thunderstorm WarningTFXLiberty, Toole41 min
Jul 13, 1:46 PM MDTSevere Thunderstorm WarningTFXLiberty24 min
Jul 13, 2:29 PM MDTSevere Thunderstorm WarningBYZBig Horn44 min
Jul 13, 2:37 PM MDTSevere Thunderstorm WarningTFXBlaine, Fergus38 min
Jul 13, 2:53 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin, Meagher52 min
Jul 13, 2:53 PM MDTSevere Thunderstorm WarningTFXBlaine52 min
Jul 13, 3:29 PM MDTSevere Thunderstorm WarningGGWPhillips42 min
Jul 13, 4:01 PM MDTSevere Thunderstorm WarningBYZBig Horn, Powder River44 min
Jul 13, 4:09 PM MDTSevere Thunderstorm WarningGGWGarfield, Petroleum, Phillips66 min
Jul 13, 4:53 PM MDTSevere Thunderstorm WarningBYZMusselshell37 min
Jul 13, 5:02 PM MDTSevere Thunderstorm WarningGGWPhillips, Valley58 min
Jul 13, 5:09 PM MDTSevere Thunderstorm WarningGGWGarfield, Valley66 min
Jul 13, 5:47 PM MDTSevere Thunderstorm WarningGGWValley58 min
Jul 13, 6:03 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone57 min
Jul 13, 6:32 PM MDTSevere Thunderstorm WarningGGWValley58 min
Jul 13, 6:57 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone63 min
Jul 13, 7:05 PM MDTSevere Thunderstorm WarningBYZTreasure55 min
Jul 13, 7:06 PM MDTSevere Thunderstorm WarningGGWMcCone, Roosevelt, Valley54 min
Jul 13, 7:43 PM MDTSevere Thunderstorm WarningBYZRosebud54 min
Jul 15, 4:23 PM MDTSevere Thunderstorm WarningTFXPondera, Toole52 min
Jul 24, 3:22 PM MDTSevere Thunderstorm WarningTFXMadison38 min
Jul 24, 5:13 PM MDTSevere Thunderstorm WarningMSODeer Lodge32 min
Jul 24, 5:37 PM MDTSevere Thunderstorm WarningMSOPowell38 min
Jul 24, 5:43 PM MDTSevere Thunderstorm WarningMSODeer Lodge21 min
Jul 25, 5:57 PM MDTSevere Thunderstorm WarningTFXTeton48 min
Jul 26, 1:44 PM MDTSevere Thunderstorm WarningTFXFergus35 min
Jul 26, 3:40 PM MDTSevere Thunderstorm WarningTFXTeton39 min
Jul 26, 3:43 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Fergus47 min
Jul 26, 4:31 PM MDTSevere Thunderstorm WarningMSOGranite44 min
Jul 26, 5:10 PM MDTSevere Thunderstorm WarningGGWPhillips24 min
Jul 26, 5:20 PM MDTSevere Thunderstorm WarningMSOGranite, Missoula40 min
Jul 26, 5:56 PM MDTSevere Thunderstorm WarningMSOGranite, Missoula, Powell49 min
Jul 26, 6:01 PM MDTSevere Thunderstorm WarningGGWGarfield21 min
Aug 4, 3:27 PM MDTSevere Thunderstorm WarningBYZBig Horn63 min
Aug 4, 3:56 PM MDTSevere Thunderstorm WarningBYZBig Horn64 min
Aug 4, 4:39 PM MDTSevere Thunderstorm WarningBYZBig Horn, Powder River36 min
Aug 4, 6:44 PM MDTSevere Thunderstorm WarningBYZStillwater, Yellowstone31 min
Aug 4, 7:16 PM MDTSevere Thunderstorm WarningBYZYellowstone29 min
Aug 5, 8:31 PM MDTSevere Thunderstorm WarningMSOFlathead, Lincoln44 min
Aug 6, 1:04 PM MDTSevere Thunderstorm WarningTFXBeaverhead41 min
Aug 6, 1:46 PM MDTSevere Thunderstorm WarningTFXBeaverhead44 min
Aug 6, 1:54 PM MDTSevere Thunderstorm WarningMSODeer Lodge, Silver Bow51 min
Aug 6, 2:41 PM MDTSevere Thunderstorm WarningMSODeer Lodge, Silver Bow49 min
Aug 6, 2:50 PM MDTSevere Thunderstorm WarningTFXJefferson, Lewis and Clark55 min
Aug 6, 4:06 PM MDTSevere Thunderstorm WarningBYZSweet Grass54 min
Aug 6, 4:19 PM MDTSevere Thunderstorm WarningMSOSilver Bow36 min
Aug 6, 4:32 PM MDTSevere Thunderstorm WarningTFXMeagher43 min
Aug 6, 5:00 PM MDTSevere Thunderstorm WarningBYZStillwater, Sweet Grass60 min
Aug 6, 5:02 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin, Meagher43 min
Aug 6, 5:12 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin48 min
Aug 6, 5:19 PM MDTSevere Thunderstorm WarningTFXMeagher41 min
Aug 6, 5:30 PM MDTSevere Thunderstorm WarningTFXGallatin, Meagher60 min
Aug 6, 5:59 PM MDTSevere Thunderstorm WarningBYZStillwater61 min
Aug 6, 6:01 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin44 min
Aug 6, 6:04 PM MDTSevere Thunderstorm WarningTFXBroadwater, Gallatin41 min
Aug 6, 6:41 PM MDTSevere Thunderstorm WarningTFXMeagher28 min
Aug 6, 6:44 PM MDTSevere Thunderstorm WarningTFXFergus48 min
Aug 6, 6:55 PM MDTSevere Thunderstorm WarningGGWPhillips65 min
Aug 6, 7:34 PM MDTSevere Thunderstorm WarningGGWPetroleum56 min
Aug 6, 7:57 PM MDTSevere Thunderstorm WarningGGWPhillips49 min
Aug 7, 7:02 AM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Teton18 min
Aug 7, 4:27 PM MDTSevere Thunderstorm WarningBYZBig Horn63 min
Aug 7, 5:00 PM MDTSevere Thunderstorm WarningBYZBig Horn30 min
Aug 7, 5:26 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud64 min
Aug 7, 5:35 PM MDTSevere Thunderstorm WarningBYZMusselshell, Yellowstone55 min
Aug 7, 5:47 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud58 min
Aug 7, 6:15 PM MDTSevere Thunderstorm WarningBYZMusselshell, Yellowstone60 min
Aug 7, 6:30 PM MDTSevere Thunderstorm WarningBYZPowder River, Rosebud60 min
Aug 7, 6:43 PM MDTSevere Thunderstorm WarningBYZPowder River, Rosebud62 min
Aug 7, 6:44 PM MDTSevere Thunderstorm WarningBYZBig Horn46 min
Aug 7, 7:16 PM MDTSevere Thunderstorm WarningBYZPowder River42 min
Aug 7, 7:23 PM MDTSevere Thunderstorm WarningBYZCuster52 min
Aug 7, 7:32 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud20 min
Aug 7, 7:41 PM MDTSevere Thunderstorm WarningBYZCarter, Custer, Powder River34 min
Aug 7, 7:46 PM MDTSevere Thunderstorm WarningBYZPowder River13 min
Aug 7, 8:05 PM MDTSevere Thunderstorm WarningBYZCarter, Custer, Fallon55 min
Aug 7, 8:45 PM MDTSevere Thunderstorm WarningBYZCarter, Fallon45 min
Aug 7, 8:46 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Wibaux37 min
Aug 7, 8:50 PM MDTSevere Thunderstorm WarningBYZCarter55 min
Aug 8, 5:01 PM MDTSevere Thunderstorm WarningBYZCarter48 min
Aug 13, 2:54 PM MDTSevere Thunderstorm WarningMSORavalli21 min
Aug 13, 6:21 PM MDTSevere Thunderstorm WarningBYZSweet Grass, Wheatland53 min
Aug 13, 8:20 PM MDTSevere Thunderstorm WarningBYZMusselshell53 min
Aug 13, 10:51 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Wibaux54 min
Aug 13, 11:47 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Richland, Wibaux58 min
Aug 14, 12:44 AM MDTSevere Thunderstorm WarningGGWRichland32 min
Aug 14, 1:50 AM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt40 min
Aug 14, 2:32 AM MDTSevere Thunderstorm WarningGGWDawson, Richland28 min
Aug 14, 2:30 PM MDTSevere Thunderstorm WarningTFXGallatin18 min
Aug 14, 2:32 PM MDTSevere Thunderstorm WarningBYZPark52 min
Aug 14, 2:47 PM MDTSevere Thunderstorm WarningBYZWheatland50 min
Aug 14, 7:05 PM MDTSevere Thunderstorm WarningGGWGarfield55 min
Aug 14, 7:15 PM MDTSevere Thunderstorm WarningBYZMusselshell53 min
Aug 14, 7:27 PM MDTSevere Thunderstorm WarningBYZBig Horn, Rosebud52 min
Aug 14, 7:51 PM MDTSevere Thunderstorm WarningBYZRosebud54 min
Aug 14, 7:59 PM MDTSevere Thunderstorm WarningGGWGarfield61 min
Aug 14, 8:49 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone56 min
Aug 14, 9:08 PM MDTSevere Thunderstorm WarningGGWGarfield51 min
Aug 14, 9:44 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland61 min
Aug 14, 10:44 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland61 min
Aug 14, 10:46 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Prairie49 min
Aug 14, 11:46 PM MDTSevere Thunderstorm WarningGGWDawson, Richland59 min
Aug 21, 6:31 PM MDTSevere Thunderstorm WarningMSOPowell22 min
Aug 21, 6:37 PM MDTSevere Thunderstorm WarningTFXLewis and Clark38 min
Aug 21, 7:04 PM MDTSevere Thunderstorm WarningMSOGranite, Powell41 min
Aug 21, 7:38 PM MDTSevere Thunderstorm WarningMSOGranite, Powell37 min
Aug 21, 8:10 PM MDTSevere Thunderstorm WarningMSOGranite, Powell50 min
Aug 22, 8:33 PM MDTSevere Thunderstorm WarningBYZWheatland25 min
Aug 23, 7:40 PM MDTSevere Thunderstorm WarningGGWMcCone65 min
Aug 23, 8:02 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland58 min
Aug 23, 8:30 PM MDTSevere Thunderstorm WarningGGWMcCone, Roosevelt, Valley60 min
Aug 23, 8:59 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland, Roosevelt61 min
Aug 23, 9:28 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt, Valley30 min
Aug 23, 9:34 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland56 min
Aug 23, 9:46 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt59 min
Aug 23, 10:32 PM MDTSevere Thunderstorm WarningGGWDawson, Richland, Roosevelt41 min
Aug 23, 10:42 PM MDTSevere Thunderstorm WarningGGWRichland33 min
Aug 23, 11:15 PM MDTSevere Thunderstorm WarningGGWRichland45 min
Sep 6, 9:01 PM MDTSevere Thunderstorm WarningGGWPhillips, Valley59 min
Sep 13, 5:16 PM MDTSevere Thunderstorm WarningBYZCuster29 min
Sep 13, 5:26 PM MDTSevere Thunderstorm WarningBYZCuster64 min
Sep 13, 5:28 PM MDTSevere Thunderstorm WarningGGWGarfield, McCone, Prairie62 min
Sep 13, 6:12 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie63 min
Sep 13, 7:04 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie56 min
Sep 13, 7:08 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie, Wibaux52 min
Sep 13, 7:43 PM MDTSevere Thunderstorm WarningGGWGarfield, Valley62 min
Sep 13, 7:52 PM MDTSevere Thunderstorm WarningGGWDawson, Wibaux37 min
Sep 13, 7:58 PM MDTSevere Thunderstorm WarningGGWDawson62 min
Sep 13, 8:53 PM MDTSevere Thunderstorm WarningGGWDawson, Prairie67 min
Sep 13, 9:20 PM MDTSevere Thunderstorm WarningGGWDawson, Richland55 min
Sep 13, 10:11 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Valley64 min
Sep 13, 10:20 PM MDTSevere Thunderstorm WarningGGWMcCone55 min
Sep 14, 1:32 AM MDTSevere Thunderstorm WarningGGWDaniels, Valley58 min

By county

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

13 more counties

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.