Alert archive / Montana / Fallon County
Weather alerts in Fallon County, Montana, 2009
97 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Fallon County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 97
- Warnings
- 21
- Watches
- 22
- Advisories
- 17
- Busiest month
- July29 alerts
- Busiest day
- July 1, 20095 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Fallon County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 9 | 5 | 44% | 11 | 55% | 25 min |
| Flash flood warnings | 1 | 1 | 0% | 3 | 67% | 19 min |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Billings, MT: severe thunderstorm warnings | 85 | 28 | 67% | 63 | 60% | 23 min |
| NWS Billings, MT: flash flood warnings | 8 | 3 | 63% | 8 | 50% | 11 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 2, 8:56 PM MST | Wind Chill Advisory | BYZ | 21 hr |
| Jan 6, 3:37 PM MST | Winter Weather Advisory | BYZ | 43 hr |
| Jan 8, 10:18 AM MST | Ice Storm Warning | BYZ | 6 hr |
| Jan 9, 8:43 AM MST | Winter Weather Advisory | BYZ | 5 hr |
| Jan 10, 3:37 PM MST | High Wind Watch | BYZ | 24 hr |
| Jan 11, 3:36 PM MST | Blizzard Warning | BYZ | 18 hr |
| Jan 12, 4:34 AM MST | Mesoscale Discussion | SPC | 4 hr |
| Feb 9, 2:39 AM MST | Winter Weather Advisory | BYZ | 18 hr |
| Feb 26, 10:12 AM MST | Winter Weather Advisory | BYZ | 26 hr |
| Mar 7, 3:16 PM MST | Winter Weather Advisory | BYZ | 61 hr |
| Mar 8, 4:42 AM MDT | Winter Storm Watch | BYZ | 23 hr |
| Mar 21, 4:29 AM MDT | Blizzard Watch | BYZ | 35 hr |
| Mar 22, 3:58 PM MDT | Blizzard Warning | BYZ | 44 hr |
| Mar 23, 11:06 AM MDT | Mesoscale Discussion | SPC | 5 hr |
| Mar 27, 3:11 PM MDT | Winter Storm Watch | BYZ | 22 hr |
| Mar 28, 3:11 AM MDT | Blizzard Watch | BYZ | 25 hr |
| Mar 29, 3:48 AM MDT | Blizzard Warning | BYZ | 38 hr |
| Mar 29, 9:03 PM MDT | Mesoscale Discussion | SPC | 6 hr |
| Apr 25, 2:28 PM MDT | Winter Weather Advisory | BYZ | 37 hr |
| May 12, 4:01 PM MDT | High Wind Watch | BYZ | 12 hr |
| May 13, 3:56 AM MDT | High Wind Warning | BYZ | 13 hr |
| Jun 14, 4:09 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 15, 2:54 PM MDT | Special Weather Statement | BYZ | 2 hr |
| Jun 15, 5:10 PM MDT | Special Weather Statement | BYZ | 80 min |
| Jun 15, 7:23 PM MDT | Flash Flood Warning | BYZ | 4 hr |
| Jun 24, 12:46 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Jun 27, 12:40 PM MDT | Special Weather Statement | BYZ | 50 min |
| Jun 30, 2:52 PM MDT | Mesoscale Discussion | SPC | 83 min |
| Jun 30, 3:19 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 30, 6:11 PM MDT | Severe Thunderstorm Warning | BYZ | 64 min |
| Jun 30, 6:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jun 30, 6:32 PM MDT | Severe Thunderstorm Warning | BYZ | 58 min |
| Jun 30, 7:04 PM MDT | Severe Thunderstorm Warning | BYZ | 86 min |
| Jun 30, 8:40 PM MDT | Severe Thunderstorm Warning | BYZ | 33 min |
| Jul 2, 11:25 AM MDT | Mesoscale Discussion | SPC | 65 min |
| Jul 2, 11:41 AM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 2, 2:17 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Jul 2, 6:29 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Jul 4, 12:29 AM MDT | Special Weather Statement | BYZ | 61 min |
| Jul 5, 7:37 PM MDT | Special Weather Statement | BYZ | 38 min |
| Jul 5, 8:20 PM MDT | Severe Thunderstorm Warning | BYZ | 55 min |
| Jul 5, 9:20 PM MDT | Special Weather Statement | BYZ | 40 min |
| Jul 6, 4:40 PM MDT | Mesoscale Discussion | SPC | 35 min |
| Jul 6, 5:00 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 6, 7:35 PM MDT | Mesoscale Discussion | SPC | 55 min |
| Jul 6, 10:30 PM MDT | Mesoscale Discussion | SPC | 60 min |
| Jul 8, 2:40 AM MDT | Special Weather Statement | BYZ | 65 min |
| Jul 8, 1:02 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Jul 8, 2:20 PM MDT | Tornado Watch | SPC | 8 hr |
| Jul 8, 5:46 PM MDT | Mesoscale Discussion | SPC | 89 min |
| Jul 8, 6:18 PM MDT | Severe Thunderstorm Warning | BYZ | 17 min |
| Jul 8, 6:50 PM MDT | Severe Thunderstorm Warning | BYZ | 55 min |
| Jul 13, 12:27 AM MDT | Special Weather Statement | BYZ | 63 min |
| Jul 13, 1:02 PM MDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jul 13, 5:05 PM MDT | Mesoscale Discussion | SPC | 55 min |
| Jul 19, 2:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jul 19, 2:46 PM MDT | Special Weather Statement | BYZ | 59 min |
| Jul 19, 3:28 PM MDT | Special Weather Statement | BYZ | 62 min |
| Aug 7, 11:50 AM MDT | Mesoscale Discussion | SPC | 115 min |
| Aug 7, 2:38 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 7, 4:15 PM MDT | Flash Flood Watch | BYZ | 6 hr |
| Aug 7, 8:05 PM MDT | Severe Thunderstorm Warning | BYZ | 55 min |
| Aug 7, 8:45 PM MDT | Severe Thunderstorm Warning | BYZ | 45 min |
| Aug 7, 10:14 PM MDT | Special Weather Statement | BYZ | 46 min |
| Aug 14, 5:10 PM MDT | Mesoscale Discussion | SPC | 65 min |
| Aug 14, 8:00 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 14, 10:47 PM MDT | Mesoscale Discussion | SPC | 58 min |
| Aug 19, 11:16 AM MDT | Mesoscale Discussion | SPC | 119 min |
| Aug 23, 7:02 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Aug 23, 7:55 PM MDT | Tornado Watch | SPC | 5 hr |
| Aug 23, 11:01 PM MDT | Special Weather Statement | BYZ | 59 min |
| Sep 1, 4:08 PM MDT | Special Weather Statement | BYZ | 52 min |
| Sep 4, 3:37 PM MDT | Fire Weather Watch | BYZ | 37 hr |
| Sep 6, 4:46 AM MDT | Red Flag Warning | BYZ | 16 hr |
| Sep 10, 4:12 AM MDT | Red Flag Warning | BYZ | 17 hr |
| Sep 13, 1:44 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Sep 13, 2:35 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Sep 13, 6:29 PM MDT | Mesoscale Discussion | SPC | 91 min |
| Sep 16, 4:33 PM MDT | Special Weather Statement | BYZ | 57 min |
| Sep 18, 3:19 AM MDT | Fire Weather Watch | BYZ | 36 hr |
| Sep 19, 3:47 AM MDT | Red Flag Warning | BYZ | 18 hr |
| Sep 24, 2:57 PM MDT | Fire Weather Watch | BYZ | 24 hr |
| Sep 25, 2:56 PM MDT | Red Flag Warning | BYZ | 31 hr |
| Sep 28, 2:18 PM MDT | Red Flag Warning | BYZ | 31 hr |
| Oct 2, 2:48 PM MDT | Winter Storm Watch | BYZ | 49 hr |
| Oct 4, 3:31 PM MDT | Winter Weather Advisory | BYZ | 35 hr |
| Dec 8, 2:24 PM MST | Wind Chill Advisory | BYZ | 21 hr |
| Dec 9, 2:53 PM MST | Wind Chill Advisory | BYZ | 12 hr |
| Dec 11, 2:58 PM MST | Winter Storm Watch | BYZ | 24 hr |
| Dec 12, 2:57 PM MST | Winter Weather Advisory | BYZ | 50 hr |
| Dec 20, 7:39 AM MST | Dense Fog Advisory | BYZ | 3 hr |
| Dec 20, 11:16 PM MST | Winter Weather Advisory | BYZ | 16 hr |
| Dec 22, 4:17 AM MST | Winter Weather Advisory | BYZ | 41 hr |
| Dec 23, 9:06 PM MST | Wind Chill Advisory | BYZ | 13 hr |
| Dec 24, 3:01 PM MST | Wind Chill Advisory | BYZ | 13 hr |
| Dec 24, 3:01 PM MST | Winter Weather Advisory | BYZ | 13 hr |
| Dec 24, 9:37 PM MST | Winter Storm Warning | BYZ | 43 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 | 9 |
| Severe Thunderstorm Watch | 8 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 23 |
| Special Weather Statement | 14 |
| Flooding | |
| Flash Flood Warning | 1 |
| Flash Flood Watch | 1 |
| Winter | |
| Blizzard Warning | 3 |
| Ice Storm Warning | 1 |
| Winter Storm Warning | 1 |
| Blizzard Watch | 2 |
| Winter Storm Watch | 4 |
| Winter Weather Advisory | 11 |
| Cold | |
| Wind Chill Advisory | 5 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 2 |
| Fire | |
| Red Flag Warning | 5 |
| Fire Weather Watch | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe 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.