Alert archive / Utah / San Juan County
Weather alerts in San Juan County, Utah, 2013
139 weather alerts in 2013, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
San Juan County and its neighbors
Each county as a circle sized by its count in 2013. Tap one for its archive.
- Alerts
- 139
- Warnings
- 61
- Watches
- 28
- Advisories
- 43
- Busiest month
- September42 alerts
- Busiest day
- September 14, 20139 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
San Juan County, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 6 | 2 | 67% | 8 | 75% | 11 min |
| Flash flood warnings | 23 | 8 | 65% | 20 | 35% | 96 min |
Each office's whole area, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Salt Lake City, UT: tornado warnings | 0 | 1 | 0% | |||
| NWS Salt Lake City, UT: severe thunderstorm warnings | 44 | 15 | 66% | 86 | 28% | 21 min |
| NWS Salt Lake City, UT: flash flood warnings | 123 | 41 | 67% | 91 | 56% | 89 min |
| NWS Grand Junction, CO: tornado warnings | 0 | 1 | 0% | |||
| NWS Grand Junction, CO: severe thunderstorm warnings | 31 | 15 | 52% | 49 | 61% | 22 min |
| NWS Grand Junction, CO: flash flood warnings | 59 | 20 | 66% | 99 | 31% | 72 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 9, 5:37 AM MST | Winter Storm Watch | GJT | 18 hr |
| Jan 9, 11:14 PM MST | Winter Weather Advisory | GJT | 55 hr |
| Jan 25, 4:59 AM MST | Winter Weather Advisory | GJT | 58 hr |
| Jan 26, 3:16 PM MST | Winter Storm Watch | GJT | 24 hr |
| Jan 27, 5:30 AM MST | Winter Storm Warning | GJT | 5 days |
| Feb 7, 9:59 PM MST | Winter Storm Warning | GJT | 4 days |
| Feb 7, 9:59 PM MST | Winter Weather Advisory | GJT | 4 days |
| Feb 18, 3:59 PM MST | Winter Storm Watch | GJT | 23 hr |
| Feb 19, 3:05 PM MST | Winter Weather Advisory | GJT | 51 hr |
| Feb 22, 3:07 PM MST | Winter Weather Advisory | GJT | 53 hr |
| Mar 2, 2:55 PM MST | Winter Weather Advisory | GJT | 51 hr |
| Mar 6, 3:22 AM MST | Winter Storm Watch | GJT | 45 hr |
| Mar 7, 1:08 AM MST | Winter Storm Warning | GJT | 68 hr |
| Apr 6, 7:34 PM MDT | Winter Storm Watch | GJT | 26 hr |
| Apr 7, 3:53 PM MDT | Freeze Watch | GJT | 13 hr |
| Apr 7, 3:53 PM MDT | High Wind Watch | GJT | 23 hr |
| Apr 7, 9:34 PM MDT | Winter Storm Warning | GJT | 48 hr |
| Apr 8, 4:48 AM MDT | Freeze Warning | GJT | 52 hr |
| Apr 8, 4:48 AM MDT | Wind Advisory | GJT | 16 hr |
| Apr 8, 11:36 AM MDT | Mesoscale Discussion | SPC | 114 min |
| Apr 8, 3:16 PM MDT | Wind Advisory | GJT | 26 hr |
| Apr 16, 4:20 AM MDT | Wind Advisory | GJT | 16 hr |
| Apr 16, 2:40 PM MDT | Freeze Watch | GJT | 25 hr |
| Apr 17, 3:12 PM MDT | Freeze Watch | GJT | 24 hr |
| Apr 17, 3:12 PM MDT | Freeze Warning | GJT | 18 hr |
| Apr 18, 3:03 PM MDT | Freeze Warning | GJT | 18 hr |
| Apr 29, 3:32 PM MDT | Wind Advisory | GJT | 28 hr |
| May 1, 11:59 AM MDT | Freeze Watch | GJT | 4 hr |
| May 1, 11:59 AM MDT | Freeze Warning | GJT | 19 hr |
| May 2, 12:39 PM MDT | Freeze Warning | GJT | 20 hr |
| May 23, 9:33 AM MDT | Wind Advisory | GJT | 11 hr |
| Jun 11, 3:06 AM MDT | Red Flag Warning | SLC | 67 hr |
| Jun 12, 3:02 PM MDT | Wind Advisory | GJT | 29 hr |
| Jun 13, 4:09 PM MDT | Special Weather Statement | GJT | 51 min |
| Jun 14, 3:01 AM MDT | Fire Weather Watch | SLC | 24 hr |
| Jun 14, 3:03 PM MDT | Red Flag Warning | SLC | 31 hr |
| Jun 16, 1:23 PM MDT | Fire Weather Watch | SLC | 25 hr |
| Jun 16, 1:23 PM MDT | Red Flag Warning | SLC | 9 hr |
| Jun 17, 2:48 PM MDT | Red Flag Warning | SLC | 4 days |
| Jun 21, 2:47 PM MDT | Fire Weather Watch | SLC | 24 hr |
| Jun 22, 2:44 PM MDT | Red Flag Warning | SLC | 54 hr |
| Jun 29, 2:28 PM MDT | Red Flag Warning | SLC | 31 hr |
| Jul 5, 4:41 PM MDT | Severe Thunderstorm Warning | SLC | 49 min |
| Jul 15, 7:32 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Jul 15, 8:07 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 16, 5:02 PM MDT | Flash Flood Warning | SLC | 3 hr |
| Jul 16, 8:18 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 16, 11:23 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Jul 17, 8:10 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 17, 9:36 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 18, 2:23 PM MDT | Flash Flood Warning | SLC | 3 hr |
| Jul 18, 7:13 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Jul 18, 8:30 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 19, 8:26 AM MDT | Flash Flood Watch | GJT | 12 hr |
| Jul 21, 4:30 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 23, 7:29 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 28, 5:32 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 28, 11:23 PM MDT | Flash Flood Watch | GJT | 22 hr |
| Jul 29, 4:03 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Jul 29, 4:21 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Jul 29, 5:03 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Aug 2, 4:20 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Aug 6, 2:46 PM MDT | Flash Flood Watch | GJT | 32 hr |
| Aug 7, 5:33 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Aug 17, 1:00 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Aug 17, 1:09 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 23, 2:51 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 23, 3:16 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 23, 3:35 PM MDT | Flood Watch | GJT | 3 days |
| Aug 25, 5:59 PM MDT | Areal Flood Warning | GJT | 6 hr |
| Aug 26, 10:58 AM MDT | River Flood Advisory | GJT | 22 hr |
| Aug 26, 4:47 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 26, 5:18 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 26, 5:35 PM MDT | Flash Flood Warning | SLC | 5 hr |
| Aug 26, 8:02 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Aug 26, 10:36 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 27, 9:01 AM MDT | Flash Flood Watch | GJT | 11 hr |
| Aug 27, 12:18 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 27, 1:08 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Aug 31, 2:43 PM MDT | Flash Flood Watch | GJT | 14 hr |
| Sep 8, 4:02 AM MDT | Flash Flood Watch | GJT | 68 hr |
| Sep 9, 10:26 AM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 9, 1:07 PM MDT | Flash Flood Warning | SLC | 6 hr |
| Sep 9, 1:31 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 9, 4:28 PM MDT | Areal Flood Warning | GJT | 24 hr |
| Sep 9, 6:33 PM MDT | Flash Flood Warning | GJT | 6 hr |
| Sep 9, 6:50 PM MDT | Areal Flood Warning | SLC | 12 hr |
| Sep 10, 8:52 AM MDT | Areal Flood Warning | GJT | 24 hr |
| Sep 10, 9:27 AM MDT | Areal Flood Warning | SLC | 12 hr |
| Sep 10, 9:28 PM MDT | Areal Flood Warning | SLC | 12 hr |
| Sep 11, 3:32 AM MDT | Flash Flood Watch | GJT | 17 hr |
| Sep 11, 8:58 AM MDT | Areal Flood Warning | SLC | 12 hr |
| Sep 11, 8:33 PM MDT | Areal Flood Warning | SLC | 12 hr |
| Sep 13, 3:25 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 13, 11:31 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Sep 14, 3:11 AM MDT | Areal Flood Advisory | GJT | 3 hr |
| Sep 14, 10:40 AM MDT | Flash Flood Watch | GJT | 34 hr |
| Sep 14, 12:25 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 14, 1:22 PM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 14, 1:53 PM MDT | Areal Flood Warning | SLC | 8 hr |
| Sep 14, 2:52 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Sep 14, 3:22 PM MDT | Areal Flood Warning | GJT | 9 hr |
| Sep 14, 4:55 PM MDT | Areal Flood Warning | GJT | 6 hr |
| Sep 14, 6:44 PM MDT | Areal Flood Warning | GJT | 6 hr |
| Sep 17, 3:35 PM MDT | Special Weather Statement | GJT | 40 min |
| Sep 17, 3:47 PM MDT | Severe Thunderstorm Warning | GJT | 43 min |
| Sep 17, 4:29 PM MDT | Severe Thunderstorm Warning | GJT | 61 min |
| Sep 17, 4:35 PM MDT | Areal Flood Advisory | GJT | 9 hr |
| Sep 18, 2:07 PM MDT | Severe Thunderstorm Warning | GJT | 38 min |
| Sep 18, 3:06 PM MDT | Areal Flood Advisory | GJT | 3 hr |
| Sep 21, 2:50 PM MDT | Flash Flood Watch | GJT | 30 hr |
| Sep 22, 9:46 AM MDT | Mesoscale Discussion | SPC | 44 min |
| Sep 22, 10:53 AM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Sep 22, 10:57 AM MDT | Flash Flood Warning | SLC | 3 hr |
| Sep 22, 11:27 AM MDT | Special Weather Statement | GJT | 48 min |
| Sep 22, 11:43 AM MDT | Flash Flood Warning | GJT | 3 hr |
| Sep 22, 12:21 PM MDT | Severe Thunderstorm Warning | GJT | 39 min |
| Sep 22, 12:31 PM MDT | Severe Thunderstorm Warning | GJT | 44 min |
| Sep 22, 2:08 PM MDT | Mesoscale Discussion | SPC | 97 min |
| Sep 22, 2:40 PM MDT | Areal Flood Warning | GJT | 4 hr |
| Sep 24, 2:36 PM MDT | Wind Advisory | GJT | 30 hr |
| Sep 25, 2:25 PM MDT | Wind Advisory | GJT | 29 hr |
| Oct 3, 3:08 AM MDT | Freeze Watch | GJT | 22 hr |
| Oct 4, 1:03 AM MDT | Freeze Warning | GJT | 32 hr |
| Oct 9, 4:33 AM MDT | Winter Weather Advisory | GJT | 59 hr |
| Oct 27, 3:05 PM MDT | Winter Storm Watch | GJT | 23 hr |
| Oct 27, 9:35 PM MDT | Wind Advisory | GJT | 21 hr |
| Oct 28, 3:24 AM MDT | Winter Storm Warning | GJT | 48 hr |
| Nov 20, 2:54 AM MST | Winter Weather Advisory | GJT | 13 hr |
| Nov 20, 3:24 PM MST | Winter Storm Warning | GJT | 4 days |
| Nov 20, 3:24 PM MST | Winter Weather Advisory | GJT | 72 hr |
| Nov 23, 3:01 PM MST | Winter Weather Advisory | GJT | 33 hr |
| Nov 30, 4:48 AM MST | Dense Fog Advisory | GJT | 7 hr |
| Dec 1, 4:03 PM MST | Winter Storm Watch | GJT | 46 hr |
| Dec 2, 5:04 AM MST | Winter Storm Warning | GJT | 66 hr |
| Dec 2, 3:30 PM MST | Winter Weather Advisory | GJT | 50 hr |
| Dec 5, 9:12 PM MST | Winter Storm Watch | GJT | 31 hr |
| Dec 6, 2:55 PM MST | Winter Weather Advisory | GJT | 63 hr |
| Dec 18, 7:29 AM MST | Dense Fog Advisory | GJT | 3 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 | 6 |
| Severe Thunderstorm Watch | 1 |
| Mesoscale Discussion | 4 |
| Special Weather Statement | 3 |
| Flooding | |
| Areal Flood Warning | 13 |
| Flash Flood Warning | 23 |
| Flash Flood Watch | 9 |
| Flood Watch | 1 |
| Areal Flood Advisory | 19 |
| River Flood Advisory | 1 |
| Winter | |
| Winter Storm Warning | 7 |
| Winter Storm Watch | 8 |
| Winter Weather Advisory | 12 |
| Cold | |
| Freeze Warning | 6 |
| Freeze Watch | 5 |
| Wind and dust | |
| High Wind Watch | 1 |
| Wind Advisory | 9 |
| Fire | |
| Red Flag Warning | 6 |
| Fire Weather Watch | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 2 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20122014
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.