Alert archive / Utah / Salt Lake County
Weather alerts in Salt Lake County, Utah, 2018
68 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Salt Lake County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 68
- Warnings
- 23
- Watches
- 6
- Advisories
- 5
- Busiest month
- August24 alerts
- Busiest day
- August 22, 201815 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Salt Lake County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 5 | 1 | 80% | 9 | 56% | 15 min |
| Flash flood warnings | 2 | 0 | 100% | 0 |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Salt Lake City, UT: tornado warnings | 0 | 2 | 0% | |||
| NWS Salt Lake City, UT: severe thunderstorm warnings | 46 | 6 | 87% | 38 | 39% | 19 min |
| NWS Salt Lake City, UT: flash flood warnings | 71 | 18 | 75% | 41 | 54% | 80 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 |
|---|---|---|---|
| Mar 14, 1:12 PM MDT | Special Weather Statement | SLC | 48 min |
| May 13, 5:14 PM MDT | Special Weather Statement | SLC | 61 min |
| May 13, 6:14 PM MDT | Special Weather Statement | SLC | 46 min |
| May 20, 1:56 PM MDT | Special Weather Statement | SLC | 49 min |
| May 20, 2:49 PM MDT | Special Weather Statement | SLC | 41 min |
| May 20, 3:05 PM MDT | Severe Thunderstorm Warning | SLC | 25 min |
| May 27, 3:03 PM MDT | Special Weather Statement | SLC | 27 min |
| May 27, 3:24 PM MDT | Areal Flood Advisory | SLC | 66 min |
| May 27, 3:53 PM MDT | Special Weather Statement | SLC | 22 min |
| May 27, 4:04 PM MDT | Areal Flood Advisory | SLC | 56 min |
| May 30, 8:57 PM MDT | Special Weather Statement | SLC | 33 min |
| Jun 18, 10:41 AM MDT | Severe Thunderstorm Warning | SLC | 34 min |
| Jun 18, 11:11 AM MDT | Severe Thunderstorm Warning | SLC | 49 min |
| Jun 18, 12:02 PM MDT | Special Weather Statement | SLC | 28 min |
| Jun 18, 12:12 PM MDT | Severe Thunderstorm Warning | SLC | 19 min |
| Jun 26, 12:58 PM MDT | Red Flag Warning | SLC | 4 days |
| Jun 30, 2:04 PM MDT | Fire Weather Watch | SLC | 37 hr |
| Jul 1, 2:30 PM MDT | Red Flag Warning | SLC | 4 days |
| Jul 3, 1:18 PM MDT | Special Weather Statement | SLC | 27 min |
| Jul 8, 6:48 PM MDT | Special Weather Statement | SLC | 42 min |
| Jul 9, 7:10 PM MDT | Special Weather Statement | SLC | 50 min |
| Jul 11, 2:32 PM MDT | Special Weather Statement | SLC | 28 min |
| Jul 16, 10:24 PM MDT | Special Weather Statement | SLC | 51 min |
| Jul 16, 11:16 PM MDT | Special Weather Statement | SLC | 44 min |
| Jul 21, 8:35 PM MDT | Special Weather Statement | SLC | 25 min |
| Jul 21, 9:05 PM MDT | Special Weather Statement | SLC | 25 min |
| Jul 28, 9:23 AM MDT | Red Flag Warning | SLC | 36 hr |
| Aug 3, 3:08 AM MDT | Red Flag Warning | SLC | 42 hr |
| Aug 5, 9:41 AM MDT | Red Flag Warning | SLC | 11 hr |
| Aug 19, 2:41 PM MDT | Red Flag Warning | SLC | 31 hr |
| Aug 21, 7:28 PM MDT | Special Weather Statement | SLC | 47 min |
| Aug 22, 12:25 PM MDT | Mesoscale Discussion | SPC | 110 min |
| Aug 22, 12:51 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 22, 2:57 PM MDT | Mesoscale Discussion | SPC | 93 min |
| Aug 22, 3:06 PM MDT | Special Weather Statement | SLC | 39 min |
| Aug 22, 3:22 PM MDT | Severe Thunderstorm Warning | SLC | 23 min |
| Aug 22, 3:29 PM MDT | Flash Flood Warning | SLC | 91 min |
| Aug 22, 3:52 PM MDT | Special Weather Statement | SLC | 38 min |
| Aug 22, 4:24 PM MDT | Special Weather Statement | SLC | 51 min |
| Aug 22, 4:37 PM MDT | Areal Flood Advisory | SLC | 83 min |
| Aug 22, 4:42 PM MDT | Special Weather Statement | SLC | 48 min |
| Aug 22, 5:13 PM MDT | Mesoscale Discussion | SPC | 92 min |
| Aug 22, 5:18 PM MDT | Areal Flood Advisory | SLC | 87 min |
| Aug 22, 5:19 PM MDT | Special Weather Statement | SLC | 41 min |
| Aug 22, 5:58 PM MDT | Flash Flood Warning | SLC | 5 min |
| Aug 22, 6:27 PM MDT | Special Weather Statement | SLC | 33 min |
| Aug 22, 6:41 PM MDT | Special Weather Statement | SLC | 34 min |
| Aug 22, 8:23 PM MDT | Mesoscale Discussion | SPC | 67 min |
| Aug 24, 2:24 PM MDT | Fire Weather Watch | SLC | 19 hr |
| Aug 25, 9:49 AM MDT | Red Flag Warning | SLC | 35 hr |
| Aug 29, 2:54 PM MDT | Red Flag Warning | SLC | 30 hr |
| Sep 9, 2:28 PM MDT | Fire Weather Watch | SLC | 37 hr |
| Sep 10, 3:23 AM MDT | Red Flag Warning | SLC | 18 hr |
| Sep 10, 1:19 PM MDT | Red Flag Warning | SLC | 5 days |
| Sep 14, 2:33 PM MDT | Red Flag Warning | SLC | 54 hr |
| Sep 17, 12:46 PM MDT | Red Flag Warning | SLC | 32 hr |
| Sep 17, 12:46 PM MDT | Red Flag Warning | SLC | 3 days |
| Sep 20, 2:46 PM MDT | Fire Weather Watch | SLC | 21 hr |
| Sep 21, 12:03 PM MDT | Red Flag Warning | SLC | 3 days |
| Sep 26, 2:40 PM MDT | Fire Weather Watch | SLC | 37 hr |
| Sep 27, 2:40 PM MDT | Red Flag Warning | SLC | 28 hr |
| Sep 28, 3:24 AM MDT | Red Flag Warning | SLC | 66 hr |
| Oct 1, 2:12 PM MDT | Special Weather Statement | SLC | 33 min |
| Oct 1, 2:41 PM MDT | Special Weather Statement | SLC | 34 min |
| Oct 2, 8:26 PM MDT | Special Weather Statement | SLC | 49 min |
| Oct 2, 9:23 PM MDT | Areal Flood Advisory | SLC | 112 min |
| Oct 2, 9:42 PM MDT | Special Weather Statement | SLC | 63 min |
| Dec 25, 8:55 PM MST | Special Weather Statement | SLC | 65 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 | 5 |
| Severe Thunderstorm Watch | 1 |
| Mesoscale Discussion | 4 |
| Special Weather Statement | 30 |
| Flooding | |
| Flash Flood Warning | 2 |
| Areal Flood Advisory | 5 |
| Fire | |
| Red Flag Warning | 16 |
| Fire Weather Watch | 5 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe 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.