Alert archive / Idaho / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in Idaho, 2018
91 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
- 91
- Busiest month
- May62 severe thunderstorm warnings
- Busiest day
- May 31, 201817 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.
26 of 91 severe thunderstorm warnings covering Idaho in 2018 had a qualifying storm report inside them; 82 of 115 hail, wind and damage reports fell inside a warning, on average 17 minutes after it went out.
Idaho, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 91 | 26 | 71% | 115 | 71% | 17 min |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Missoula, MT: severe thunderstorm warnings | 11 | 9 | 18% | 17 | 76% | 18 min |
| NWS Spokane, WA: severe thunderstorm warnings | 8 | 3 | 63% | 15 | 20% | 12 min |
| NWS Pocatello, ID: severe thunderstorm warnings | 65 | 20 | 69% | 106 | 70% | 17 min |
| NWS Boise, ID: severe thunderstorm warnings | 40 | 6 | 85% | 16 | 44% | 24 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 7, 2:42 PM MDT | Severe Thunderstorm Warning | BOI | Ada, Boise, Elmore | 48 min |
| Apr 7, 6:50 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville, Jefferson, Madison | 40 min |
| Apr 7, 7:26 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville, Fremont, Jefferson, Madison, Teton | 20 min |
| May 6, 3:40 PM MDT | Severe Thunderstorm Warning | BOI | Valley | 50 min |
| May 6, 6:26 PM MDT | Severe Thunderstorm Warning | BOI | Payette, Washington | 34 min |
| May 6, 6:59 PM MDT | Severe Thunderstorm Warning | BOI | Payette, Washington | 16 min |
| May 6, 8:09 PM MDT | Severe Thunderstorm Warning | BOI | Valley | 23 min |
| May 12, 3:54 PM MDT | Severe Thunderstorm Warning | PIH | Butte, Clark, Jefferson | 21 min |
| May 16, 2:11 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Minidoka, Power | 38 min |
| May 16, 2:40 PM MDT | Severe Thunderstorm Warning | BOI | Twin Falls | 35 min |
| May 16, 3:27 PM MDT | Severe Thunderstorm Warning | PIH | Bannock, Bingham, Power | 38 min |
| May 17, 3:44 PM MDT | Severe Thunderstorm Warning | PIH | Oneida | 31 min |
| May 17, 4:13 PM MDT | Severe Thunderstorm Warning | PIH | Cassia, Oneida, Power | 47 min |
| May 17, 5:21 PM MDT | Severe Thunderstorm Warning | PIH | Bannock, Bingham, Power | 39 min |
| May 17, 5:59 PM MDT | Severe Thunderstorm Warning | PIH | Bannock, Bingham, Power | 46 min |
| May 20, 1:23 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Minidoka | 67 min |
| May 20, 1:30 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Power | 60 min |
| May 20, 2:07 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Minidoka | 38 min |
| May 20, 2:26 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Power | 49 min |
| May 20, 3:01 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Blaine, Power | 44 min |
| May 20, 3:40 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Blaine, Butte, Power | 50 min |
| May 20, 4:23 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville | 52 min |
| May 22, 4:48 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Lincoln | 22 min |
| May 25, 5:08 PM MDT | Severe Thunderstorm Warning | BOI | Canyon, Owyhee | 67 min |
| May 25, 5:18 PM MDT | Severe Thunderstorm Warning | BOI | Owyhee | 42 min |
| May 25, 5:23 PM MDT | Severe Thunderstorm Warning | MSO | Idaho | 37 min |
| May 25, 6:01 PM MDT | Severe Thunderstorm Warning | BOI | Canyon, Owyhee | 59 min |
| May 25, 6:34 PM MDT | Severe Thunderstorm Warning | BOI | Ada, Canyon, Owyhee | 56 min |
| May 25, 7:00 PM MDT | Severe Thunderstorm Warning | BOI | Canyon, Owyhee | 60 min |
| May 25, 7:29 PM MDT | Severe Thunderstorm Warning | BOI | Ada, Canyon, Owyhee | 31 min |
| May 25, 7:44 PM MDT | Severe Thunderstorm Warning | BOI | Washington | 61 min |
| May 25, 8:00 PM MDT | Severe Thunderstorm Warning | BOI | Ada, Canyon, Gem, Owyhee, Payette | 45 min |
| May 25, 8:05 PM MDT | Severe Thunderstorm Warning | BOI | Adams | 40 min |
| May 25, 8:13 PM MDT | Severe Thunderstorm Warning | BOI | Boise, Gem, Valley, Washington | 62 min |
| May 25, 8:41 PM MDT | Severe Thunderstorm Warning | BOI | Adams, Valley, Washington | 64 min |
| May 25, 8:51 PM MDT | Severe Thunderstorm Warning | BOI | Adams, Washington | 54 min |
| May 25, 9:48 PM MDT | Severe Thunderstorm Warning | BOI | Adams | 27 min |
| May 26, 3:09 PM MDT | Severe Thunderstorm Warning | MSO | Lemhi | 36 min |
| May 26, 3:27 PM MDT | Severe Thunderstorm Warning | PIH | Cassia, Minidoka | 33 min |
| May 26, 3:58 PM MDT | Severe Thunderstorm Warning | PIH | Cassia, Lincoln, Minidoka | 32 min |
| May 26, 4:29 PM MDT | Severe Thunderstorm Warning | PIH | Lincoln, Minidoka | 31 min |
| May 26, 4:36 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Minidoka | 24 min |
| May 27, 1:00 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Caribou | 19 min |
| May 30, 1:49 PM MDT | Severe Thunderstorm Warning | PIH | Fremont, Madison, Teton | 26 min |
| May 30, 2:01 PM MDT | Severe Thunderstorm Warning | PIH | Cassia | 44 min |
| May 30, 2:39 PM MDT | Severe Thunderstorm Warning | PIH | Bannock, Caribou, Oneida, Power | 51 min |
| May 30, 3:12 PM MDT | Severe Thunderstorm Warning | PIH | Caribou | 48 min |
| May 30, 5:46 PM MDT | Severe Thunderstorm Warning | PIH | Cassia, Minidoka | 29 min |
| May 30, 6:00 PM MDT | Severe Thunderstorm Warning | BOI | Jerome, Twin Falls | 30 min |
| May 31, 12:40 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville, Jefferson, Madison | 35 min |
| May 31, 12:49 PM MDT | Severe Thunderstorm Warning | BOI | Twin Falls | 41 min |
| May 31, 1:16 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville, Jefferson, Madison | 24 min |
| May 31, 1:27 PM MDT | Severe Thunderstorm Warning | BOI | Jerome, Twin Falls | 38 min |
| May 31, 1:33 PM MDT | Severe Thunderstorm Warning | BOI | Owyhee, Twin Falls | 27 min |
| May 31, 1:44 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville, Fremont, Jefferson, Madison | 46 min |
| May 31, 2:33 PM MDT | Severe Thunderstorm Warning | PIH | Lincoln | 31 min |
| May 31, 2:42 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Minidoka | 48 min |
| May 31, 2:58 PM MDT | Severe Thunderstorm Warning | PIH | Lincoln, Minidoka | 33 min |
| May 31, 3:02 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Blaine, Minidoka, Power | 43 min |
| May 31, 3:57 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Blaine, Bonneville, Butte, Jefferson | 44 min |
| May 31, 4:30 PM MDT | Severe Thunderstorm Warning | PIH | Cassia | 45 min |
| May 31, 4:50 PM MDT | Severe Thunderstorm Warning | PIH | Clark, Fremont, Jefferson, Madison | 40 min |
| May 31, 5:15 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville, Fremont, Jefferson, Madison, Teton | 45 min |
| May 31, 5:22 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Cassia, Power | 38 min |
| May 31, 5:24 PM MDT | Severe Thunderstorm Warning | PIH | Clark, Fremont, Jefferson, Madison | 51 min |
| May 31, 6:15 PM MDT | Severe Thunderstorm Warning | PIH | Clark, Fremont | 45 min |
| Jun 17, 1:19 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville, Jefferson, Madison | 23 min |
| Jun 17, 1:25 PM MDT | Severe Thunderstorm Warning | PIH | Fremont, Madison | 50 min |
| Jun 17, 1:38 PM MDT | Severe Thunderstorm Warning | PIH | Fremont, Jefferson, Madison, Teton | 37 min |
| Jun 17, 1:40 PM MDT | Severe Thunderstorm Warning | PIH | Bear Lake, Caribou | 50 min |
| Jun 20, 8:07 PM MDT | Severe Thunderstorm Warning | BOI | Owyhee | 38 min |
| Jun 21, 1:24 PM MDT | Severe Thunderstorm Warning | PIH | Butte, Custer | 51 min |
| Jun 21, 3:49 PM MDT | Severe Thunderstorm Warning | PIH | Fremont | 15 min |
| Jul 16, 5:38 PM MDT | Severe Thunderstorm Warning | PIH | Bear Lake, Franklin | 32 min |
| Jul 25, 3:27 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville, Jefferson, Madison, Teton | 48 min |
| Jul 26, 4:23 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville | 52 min |
| Aug 1, 3:24 PM MDT | Severe Thunderstorm Warning | PIH | Butte, Custer | 39 min |
| Aug 1, 4:02 PM MDT | Severe Thunderstorm Warning | PIH | Butte | 43 min |
| Aug 1, 4:44 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville, Butte | 46 min |
| Aug 1, 6:06 PM MDT | Severe Thunderstorm Warning | PIH | Bonneville, Jefferson | 39 min |
| Aug 1, 6:56 PM MDT | Severe Thunderstorm Warning | PIH | Bear Lake | 49 min |
| Aug 1, 8:48 PM MDT | Severe Thunderstorm Warning | PIH | Bear Lake | 42 min |
| Aug 17, 5:51 PM MDT | Severe Thunderstorm Warning | PIH | Blaine, Butte | 39 min |
| Aug 17, 6:19 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Blaine, Butte, Power | 41 min |
| Aug 17, 6:25 PM MDT | Severe Thunderstorm Warning | PIH | Butte, Custer | 35 min |
| Aug 22, 8:12 AM MDT | Severe Thunderstorm Warning | PIH | Bannock, Bear Lake, Franklin, Oneida | 48 min |
| Aug 22, 3:12 PM MDT | Severe Thunderstorm Warning | PIH | Bannock, Cassia, Oneida, Power | 48 min |
| Aug 22, 3:46 PM MDT | Severe Thunderstorm Warning | PIH | Clark, Fremont, Jefferson | 44 min |
| Aug 22, 4:07 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville | 38 min |
| Aug 22, 4:28 PM MDT | Severe Thunderstorm Warning | PIH | Clark, Fremont, Jefferson, Madison | 47 min |
| Aug 22, 4:41 PM MDT | Severe Thunderstorm Warning | PIH | Bingham, Bonneville | 15 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Bingham County17
- Jefferson County16
- Bonneville County15
- Blaine County15
- Madison County14
- Cassia County14
- Power County14
- Fremont County12
- Minidoka County11
- Butte County10
- Owyhee County9
- Washington County6
- Clark County6
- Bannock County6
- Canyon County6
- Teton County5
- Twin Falls County5
- Oneida County5
- Lincoln County5
- Bear Lake County5
- Ada County4
- Valley County4
- Adams County4
- Caribou County4
- Payette County3
- Custer County3
- Boise County2
- Gem County2
- Jerome County2
- Franklin County2
- Elmore County1
- Idaho County1
- Lemhi County1
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20172019
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.