Weather alerts in Utah, 2022
1,343 weather alerts in 2022, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.
Weather alerts by county
Each county as a circle sized by its count in 2022. Tap one for its archive.
- Alerts
- 1,343
- Warnings
- 370
- Watches
- 80
- Advisories
- 230
- Busiest month
- August331 alerts
- Busiest day
- October 2, 202274 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
0 of 4 tornado reports fell inside a warning.
Utah, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 4 | 0% | |||
| Severe thunderstorm warnings | 118 | 28 | 76% | 173 | 27% | 22 min |
| Flash flood warnings | 140 | 49 | 65% | 96 | 68% | 70 min |
Each office's whole area, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Grand Junction, CO: severe thunderstorm warnings | 29 | 5 | 83% | 13 | 38% | 17 min |
| NWS Grand Junction, CO: flash flood warnings | 61 | 12 | 80% | 38 | 63% | 45 min |
| NWS Salt Lake City, UT: tornado warnings | 0 | 4 | 0% | |||
| NWS Salt Lake City, UT: severe thunderstorm warnings | 108 | 28 | 74% | 176 | 27% | 22 min |
| NWS Salt Lake City, UT: flash flood warnings | 126 | 44 | 65% | 79 | 68% | 71 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
1,343 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Washington County219
- San Juan County187
- Garfield County179
- Kane County176
- Grand County169
- Salt Lake County153
- Iron County153
- Utah County136
- Tooele County135
- Box Elder County132
- Wayne County128
- Davis County121
- Emery County113
- Juab County111
- Weber County104
- Sevier County98
- Uintah County98
- Duchesne County89
- Beaver County88
- Carbon County87
- Millard County82
- Summit County81
- Wasatch County79
- Cache County76
- Morgan County71
- Piute County69
- Sanpete County68
- Rich County65
- Daggett County55
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20212023
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.