Alert archive / Utah / Salt Lake County
Weather alerts in Salt Lake County, Utah, 2017
38 weather alerts in 2017, 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 2017. Tap one for its archive.
- Alerts
- 38
- Warnings
- 14
- Watches
- 1
- Advisories
- 5
- Busiest month
- July9 alerts
- Busiest day
- May 25, 20173 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, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 5 | 1 | 80% | 3 | 33% | 13 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Salt Lake City, UT: severe thunderstorm warnings | 29 | 12 | 59% | 69 | 30% | 32 min |
| NWS Salt Lake City, UT: flash flood warnings | 49 | 10 | 80% | 25 | 48% | 103 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 22, 2:30 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 8, 1:05 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 18, 2:09 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| May 6, 1:58 PM MDT | Special Weather Statement | SLC | 47 min |
| May 6, 3:30 PM MDT | Mesoscale Discussion | SPC | 60 min |
| May 8, 5:31 PM MDT | Special Weather Statement | SLC | 29 min |
| May 8, 5:37 PM MDT | Severe Thunderstorm Warning | SLC | 23 min |
| May 24, 5:02 PM MDT | Special Weather Statement | SLC | 28 min |
| May 24, 6:28 PM MDT | Severe Thunderstorm Warning | SLC | 32 min |
| May 24, 6:47 PM MDT | Severe Thunderstorm Warning | SLC | 28 min |
| May 24, 7:13 PM MDT | Severe Thunderstorm Warning | SLC | 32 min |
| Jun 7, 2:46 AM MDT | Red Flag Warning | SLC | 5 days |
| Jun 7, 8:14 AM MDT | Red Flag Warning | SLC | 14 hr |
| Jun 20, 5:49 PM MDT | Special Weather Statement | SLC | 41 min |
| Jun 21, 3:52 PM MDT | Special Weather Statement | SLC | 23 min |
| Jun 24, 2:29 PM MDT | Red Flag Warning | SLC | 5 days |
| Jun 26, 3:06 PM MDT | Red Flag Warning | SLC | 3 days |
| Jul 5, 3:08 PM MDT | Red Flag Warning | SLC | 4 days |
| Jul 9, 2:03 PM MDT | Red Flag Warning | SLC | 30 hr |
| Jul 17, 5:52 PM MDT | Special Weather Statement | SLC | 38 min |
| Jul 17, 6:05 PM MDT | Severe Thunderstorm Warning | SLC | 40 min |
| Jul 18, 11:38 AM MDT | Red Flag Warning | SLC | 34 hr |
| Jul 26, 4:54 AM MDT | Areal Flood Advisory | SLC | 51 min |
| Jul 26, 5:49 AM MDT | Areal Flood Advisory | SLC | 116 min |
| Jul 26, 9:14 PM MDT | Special Weather Statement | SLC | 46 min |
| Jul 26, 9:43 PM MDT | Special Weather Statement | SLC | 47 min |
| Aug 9, 5:42 PM MDT | Special Weather Statement | SLC | 33 min |
| Aug 9, 6:01 PM MDT | Special Weather Statement | SLC | 89 min |
| Aug 13, 2:42 PM MDT | Special Weather Statement | SLC | 33 min |
| Aug 13, 3:12 PM MDT | Areal Flood Advisory | SLC | 2 hr |
| Aug 13, 3:24 PM MDT | Special Weather Statement | SLC | 36 min |
| Aug 15, 5:02 PM MDT | Special Weather Statement | SLC | 28 min |
| Aug 23, 3:02 PM MDT | Special Weather Statement | SLC | 43 min |
| Aug 28, 2:52 PM MDT | Fire Weather Watch | SLC | 23 hr |
| Aug 29, 1:38 PM MDT | Red Flag Warning | SLC | 34 hr |
| Sep 7, 1:41 PM MDT | Red Flag Warning | SLC | 32 hr |
| Sep 15, 9:11 AM MDT | Areal Flood Advisory | SLC | 64 min |
| Sep 15, 10:16 AM MDT | Areal Flood Advisory | SLC | 119 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 |
| Mesoscale Discussion | 4 |
| Special Weather Statement | 14 |
| Flooding | |
| Areal Flood Advisory | 5 |
| Fire | |
| Red Flag Warning | 9 |
| Fire Weather Watch | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20162018
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.