Alert archive / Montana / Roosevelt County
Weather alerts in Roosevelt County, Montana, 2020
109 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Roosevelt County and its neighbors
Each county as a circle sized by its count in 2020. Tap one for its archive.
- Alerts
- 109
- Warnings
- 43
- Watches
- 17
- Advisories
- 20
- Busiest month
- July34 alerts
- Busiest day
- May 21, 20207 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Roosevelt County, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 25 | 14 | 44% | 7 | 57% | 21 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Glasgow, MT: tornado warnings | 3 | 2 | 33% | 2 | 100% | 0 min |
| NWS Glasgow, MT: severe thunderstorm warnings | 79 | 46 | 42% | 174 | 74% | 25 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 | Lasted |
|---|---|---|---|
| Jan 3, 2:55 PM MST | High Wind Watch | GGW | 12 hr |
| Jan 3, 2:55 PM MST | High Wind Warning | GGW | 36 hr |
| Jan 12, 3:00 AM MST | Winter Weather Advisory | GGW | 41 hr |
| Jan 13, 2:19 PM MST | Wind Chill Advisory | GGW | 6 days |
| Jan 14, 1:31 PM MST | Wind Chill Warning | GGW | 46 hr |
| Jan 14, 1:31 PM MST | Wind Chill Advisory | GGW | 19 hr |
| Jan 19, 2:16 PM MST | Wind Chill Advisory | GGW | 18 hr |
| Jan 23, 6:48 PM MST | Dense Fog Advisory | GGW | 13 hr |
| Jan 29, 3:13 AM MST | Dense Fog Advisory | GGW | 6 hr |
| Jan 30, 1:13 AM MST | Dense Fog Advisory | GGW | 8 hr |
| Feb 11, 3:06 AM MST | Winter Weather Advisory | GGW | 30 hr |
| Feb 12, 3:17 AM MST | Wind Chill Advisory | GGW | 31 hr |
| Feb 18, 1:45 PM MST | Wind Chill Advisory | GGW | 21 hr |
| Feb 23, 2:53 AM MST | Winter Weather Advisory | GGW | 48 hr |
| Mar 2, 2:06 PM MST | High Wind Watch | GGW | 13 hr |
| Mar 11, 12:38 AM MDT | River Flood Warning | GGW | 24 hr |
| Mar 11, 2:43 PM MDT | Winter Storm Watch | GGW | 37 hr |
| Mar 13, 3:27 AM MDT | Winter Weather Advisory | GGW | 3 days |
| Mar 31, 3:21 AM MDT | Winter Weather Advisory | GGW | 39 hr |
| Apr 19, 3:11 AM MDT | Red Flag Warning | GGW | 18 hr |
| Apr 21, 10:28 AM MDT | Red Flag Warning | GGW | 11 hr |
| Apr 24, 12:48 PM MDT | Special Weather Statement | GGW | 42 min |
| Apr 25, 3:05 PM MDT | Fire Weather Watch | GGW | 11 hr |
| Apr 26, 2:33 AM MDT | Red Flag Warning | GGW | 17 hr |
| Apr 27, 3:04 AM MDT | Fire Weather Watch | GGW | 24 hr |
| Apr 27, 10:00 PM MDT | Special Weather Statement | GGW | 60 min |
| Apr 28, 3:13 AM MDT | Red Flag Warning | GGW | 18 hr |
| May 1, 12:43 AM MDT | Special Weather Statement | GGW | 47 min |
| May 20, 1:43 PM MDT | Mesoscale Discussion | SPC | 92 min |
| May 20, 3:11 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| May 20, 6:27 PM MDT | Mesoscale Discussion | SPC | 93 min |
| May 20, 8:36 PM MDT | Severe Thunderstorm Warning | GGW | 39 min |
| May 20, 8:44 PM MDT | Severe Thunderstorm Warning | GGW | 76 min |
| May 20, 9:10 PM MDT | Mesoscale Discussion | SPC | 95 min |
| May 20, 9:33 PM MDT | Severe Thunderstorm Warning | GGW | 57 min |
| May 20, 9:35 PM MDT | Severe Thunderstorm Warning | GGW | 55 min |
| May 20, 10:21 PM MDT | Special Weather Statement | GGW | 54 min |
| Jun 6, 4:49 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 7, 2:59 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 29, 3:56 PM MDT | Tornado Watch | SPC | 8 hr |
| Jun 29, 6:43 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 1, 7:04 PM MDT | Special Weather Statement | GGW | 56 min |
| Jul 3, 5:30 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 3, 7:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jul 4, 5:39 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 4, 8:46 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Jul 4, 9:33 PM MDT | Severe Thunderstorm Warning | GGW | 57 min |
| Jul 4, 9:52 PM MDT | Areal Flood Advisory | GGW | 2 hr |
| Jul 4, 10:07 PM MDT | Special Weather Statement | GGW | 68 min |
| Jul 4, 10:45 PM MDT | Severe Thunderstorm Warning | GGW | 48 min |
| Jul 5, 4:09 PM MDT | Severe Thunderstorm Warning | GGW | 35 min |
| Jul 6, 3:32 PM MDT | Severe Thunderstorm Warning | GGW | 58 min |
| Jul 7, 12:47 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 7, 1:14 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 7, 5:12 PM MDT | Severe Thunderstorm Warning | GGW | 63 min |
| Jul 7, 5:13 PM MDT | Mesoscale Discussion | SPC | 92 min |
| Jul 7, 5:25 PM MDT | Severe Thunderstorm Warning | GGW | 65 min |
| Jul 7, 6:13 PM MDT | Severe Thunderstorm Warning | GGW | 62 min |
| Jul 7, 6:27 PM MDT | Severe Thunderstorm Warning | GGW | 63 min |
| Jul 7, 7:04 PM MDT | Severe Thunderstorm Warning | GGW | 56 min |
| Jul 7, 7:24 PM MDT | Severe Thunderstorm Warning | GGW | 66 min |
| Jul 10, 1:08 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 10, 1:39 PM MDT | Special Weather Statement | GGW | 66 min |
| Jul 10, 2:41 PM MDT | Special Weather Statement | GGW | 79 min |
| Jul 10, 2:43 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 10, 2:45 PM MDT | Severe Thunderstorm Warning | GGW | 60 min |
| Jul 18, 12:16 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Jul 20, 5:09 PM MDT | Special Weather Statement | GGW | 51 min |
| Jul 23, 2:27 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 23, 4:54 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 23, 5:14 PM MDT | Special Weather Statement | GGW | 61 min |
| Jul 23, 5:46 PM MDT | Severe Thunderstorm Warning | GGW | 44 min |
| Jul 23, 6:17 PM MDT | Special Weather Statement | GGW | 43 min |
| Jul 23, 8:40 PM MDT | Severe Thunderstorm Warning | GGW | 15 min |
| Jul 30, 5:02 PM MDT | Special Weather Statement | GGW | 43 min |
| Aug 11, 12:41 PM MDT | Red Flag Warning | GGW | 32 hr |
| Aug 12, 5:33 PM MDT | Severe Thunderstorm Warning | GGW | 42 min |
| Aug 12, 6:13 PM MDT | Severe Thunderstorm Warning | GGW | 48 min |
| Aug 16, 2:08 PM MDT | Heat Advisory | GGW | 53 hr |
| Aug 17, 2:44 PM MDT | Red Flag Warning | GGW | 29 hr |
| Aug 19, 3:18 AM MDT | Heat Advisory | GGW | 17 hr |
| Aug 20, 9:47 AM MDT | Red Flag Warning | GGW | 17 hr |
| Aug 20, 9:43 PM MDT | Severe Thunderstorm Warning | GGW | 62 min |
| Aug 20, 10:43 PM MDT | Severe Thunderstorm Warning | GGW | 62 min |
| Aug 27, 4:03 PM MDT | Severe Thunderstorm Warning | GGW | 28 min |
| Aug 27, 4:49 PM MDT | Special Weather Statement | GGW | 56 min |
| Aug 27, 5:48 PM MDT | Special Weather Statement | GGW | 57 min |
| Aug 30, 9:48 AM MDT | Red Flag Warning | GGW | 10 hr |
| Aug 31, 3:18 AM MDT | Red Flag Warning | GGW | 66 hr |
| Sep 2, 9:44 AM MDT | High Wind Warning | GGW | 10 hr |
| Sep 22, 2:07 PM MDT | Fire Weather Watch | GGW | 24 hr |
| Sep 23, 2:17 PM MDT | Red Flag Warning | GGW | 31 hr |
| Oct 20, 1:29 PM MDT | Winter Weather Advisory | GGW | 45 hr |
| Oct 21, 10:27 AM MDT | Winter Storm Warning | GGW | 22 hr |
| Oct 21, 7:06 PM MDT | Special Weather Statement | GGW | 84 min |
| Oct 30, 7:08 PM MDT | Severe Thunderstorm Warning | GGW | 52 min |
| Oct 30, 7:43 PM MDT | Severe Thunderstorm Warning | GGW | 38 min |
| Oct 30, 7:52 PM MDT | Special Weather Statement | GGW | 53 min |
| Oct 30, 7:56 PM MDT | Severe Thunderstorm Warning | GGW | 56 min |
| Oct 30, 8:56 PM MDT | Special Weather Statement | GGW | 49 min |
| Nov 5, 2:26 PM MST | Winter Storm Watch | GGW | 47 hr |
| Nov 6, 2:45 PM MST | Winter Storm Warning | GGW | 69 hr |
| Nov 10, 2:44 AM MST | Dense Fog Advisory | GGW | 6 hr |
| Nov 18, 2:28 PM MST | Winter Weather Advisory | GGW | 21 hr |
| Dec 10, 11:40 AM MST | Dense Fog Advisory | GGW | 44 hr |
| Dec 18, 12:17 PM MST | High Wind Watch | GGW | 39 hr |
| Dec 20, 2:49 AM MST | High Wind Warning | GGW | 15 hr |
| Dec 21, 12:02 PM MST | High Wind Watch | GGW | 15 hr |
| Dec 22, 3:05 AM MST | High Wind Warning | GGW | 20 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
| Product | Alerts |
|---|---|
| Severe storms | |
| Severe Thunderstorm Warning | 25 |
| Severe Thunderstorm Watch | 7 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 12 |
| Special Weather Statement | 17 |
| Flooding | |
| River Flood Warning | 1 |
| Areal Flood Advisory | 1 |
| Winter | |
| Winter Storm Warning | 2 |
| Winter Storm Watch | 2 |
| Winter Weather Advisory | 7 |
| Heat | |
| Heat Advisory | 2 |
| Cold | |
| Wind Chill Warning | 1 |
| Wind Chill Advisory | 5 |
| Wind and dust | |
| High Wind Warning | 4 |
| High Wind Watch | 4 |
| Fire | |
| Red Flag Warning | 10 |
| Fire Weather Watch | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 5 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20192021
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.