Alert archive / Utah / Box Elder County
Weather alerts in Box Elder County, Utah, 2016
42 weather alerts in 2016, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Box Elder County and its neighbors
Each county as a circle sized by its count in 2016. Tap one for its archive.
- Alerts
- 42
- Warnings
- 28
- Watches
- 7
- Advisories
- 0
- Busiest month
- August13 alerts
- Busiest day
- September 22, 20166 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Box Elder County, 2016
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 15 | 10 | 33% | 25 | 28% | 24 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2016
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Salt Lake City, UT: tornado warnings | 0 | 4 | 0% | |||
| NWS Salt Lake City, UT: severe thunderstorm warnings | 65 | 28 | 57% | 183 | 26% | 18 min |
| NWS Salt Lake City, UT: flash flood warnings | 32 | 8 | 75% | 14 | 71% | 51 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 |
|---|---|---|---|
| May 6, 12:57 PM MDT | Mesoscale Discussion | SPC | 93 min |
| May 6, 4:05 PM MDT | Severe Thunderstorm Warning | SLC | 25 min |
| May 6, 4:32 PM MDT | Severe Thunderstorm Warning | SLC | 28 min |
| May 6, 4:59 PM MDT | Severe Thunderstorm Warning | SLC | 31 min |
| May 19, 5:25 PM MDT | Severe Thunderstorm Warning | SLC | 50 min |
| May 24, 4:28 PM MDT | Special Weather Statement | SLC | 32 min |
| Jun 6, 1:55 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Jun 12, 5:22 PM MDT | Special Weather Statement | SLC | 53 min |
| Jun 12, 7:11 PM MDT | Severe Thunderstorm Warning | SLC | 49 min |
| Jun 12, 7:56 PM MDT | Severe Thunderstorm Warning | SLC | 49 min |
| Jun 12, 8:40 PM MDT | Severe Thunderstorm Warning | SLC | 65 min |
| Jun 13, 5:45 PM MDT | Severe Thunderstorm Warning | SLC | 30 min |
| Jun 28, 2:17 PM MDT | Red Flag Warning | SLC | 32 hr |
| Jul 8, 2:27 AM MDT | Red Flag Warning | SLC | 68 hr |
| Jul 15, 2:55 AM MDT | Red Flag Warning | SLC | 4 days |
| Jul 28, 2:49 PM MDT | Fire Weather Watch | SLC | 24 hr |
| Jul 28, 2:49 PM MDT | Red Flag Warning | SLC | 6 days |
| Jul 30, 6:45 PM MDT | Special Weather Statement | SLC | 30 min |
| Aug 2, 3:44 PM MDT | Severe Thunderstorm Warning | SLC | 46 min |
| Aug 4, 2:54 PM MDT | Fire Weather Watch | SLC | 12 hr |
| Aug 5, 2:47 AM MDT | Red Flag Warning | SLC | 21 hr |
| Aug 5, 2:48 PM MDT | Fire Weather Watch | SLC | 31 hr |
| Aug 6, 9:30 PM MDT | Red Flag Warning | SLC | 24 hr |
| Aug 7, 3:06 PM MDT | Fire Weather Watch | SLC | 24 hr |
| Aug 8, 3:22 PM MDT | Red Flag Warning | SLC | 30 hr |
| Aug 9, 2:59 PM MDT | Fire Weather Watch | SLC | 12 hr |
| Aug 10, 3:15 AM MDT | Red Flag Warning | SLC | 24 hr |
| Aug 13, 1:55 PM MDT | Fire Weather Watch | SLC | 24 hr |
| Aug 14, 2:24 PM MDT | Red Flag Warning | SLC | 34 hr |
| Aug 30, 2:18 PM MDT | Fire Weather Watch | SLC | 12 hr |
| Aug 31, 2:29 AM MDT | Red Flag Warning | SLC | 49 hr |
| Sep 2, 3:52 AM MDT | Red Flag Warning | SLC | 66 hr |
| Sep 10, 2:19 PM MDT | Red Flag Warning | SLC | 3 days |
| Sep 11, 2:13 PM MDT | Red Flag Warning | SLC | 47 hr |
| Sep 21, 7:54 PM MDT | Severe Thunderstorm Warning | SLC | 51 min |
| Sep 22, 1:06 PM MDT | Severe Thunderstorm Warning | SLC | 24 min |
| Sep 22, 2:15 PM MDT | Special Weather Statement | SLC | 30 min |
| Sep 22, 3:25 PM MDT | Severe Thunderstorm Warning | SLC | 35 min |
| Sep 22, 3:54 PM MDT | Severe Thunderstorm Warning | SLC | 36 min |
| Sep 22, 4:22 PM MDT | Severe Thunderstorm Warning | SLC | 38 min |
| Oct 2, 12:38 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Dec 16, 11:20 AM MST | Severe Thunderstorm Warning | SLC | 25 min |
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 | 15 |
| Mesoscale Discussion | 3 |
| Special Weather Statement | 4 |
| Fire | |
| Red Flag Warning | 13 |
| Fire Weather Watch | 7 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20152017
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.