Alert archive / Utah / San Juan County

Weather alerts in San Juan County, Utah, 2016

79 weather alerts in 2016, 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 2016. Tap one for its archive.

Alerts
79
Warnings
25
Watches
20
Advisories
30
Busiest month
July16 alerts
Busiest day
July 15, 20164 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, 2016

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings10100%0
Flash flood warnings030%

Each office's whole area, 2016

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Grand Junction, CO: severe thunderstorm warnings13377%1926%7 min
NWS Grand Junction, CO: flash flood warnings14193%176%95 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.

IssuedProductOfficeLasted
Jan 5, 12:50 AM MSTWinter Weather AdvisoryGJT8 hr
Jan 5, 10:58 AM MSTWinter Storm WatchGJT5 hr
Jan 5, 3:30 PM MSTWinter Weather AdvisoryGJT46 hr
Jan 7, 4:51 AM MSTDense Fog AdvisoryGJT5 hr
Jan 7, 1:31 PM MSTWinter Weather AdvisoryGJT27 hr
Jan 7, 11:15 PM MSTWinter Storm WarningGJT18 hr
Jan 13, 4:48 AM MSTDense Fog AdvisoryGJT5 hr
Jan 28, 10:03 PM MSTWinter Storm WarningGJT5 days
Jan 28, 10:03 PM MSTWinter Weather AdvisoryGJT59 hr
Jan 29, 3:07 PM MSTWinter Storm WatchGJT50 hr
Jan 30, 4:27 PM MSTWinter Storm WarningGJT68 hr
Feb 17, 12:34 PM MSTWind AdvisoryGJT32 hr
Mar 13, 11:40 PM MDTWind AdvisoryGJT23 hr
Mar 22, 3:12 AM MDTWind AdvisoryGJT18 hr
Mar 27, 8:48 PM MDTWinter Weather AdvisoryGJT60 hr
Apr 14, 3:55 AM MDTWinter Storm WatchGJT9 hr
Apr 14, 3:55 AM MDTWinter Storm WarningGJT3 days
Apr 16, 4:30 AM MDTWind AdvisoryGJT8 hr
Apr 23, 3:06 AM MDTWind AdvisoryGJT17 hr
Apr 25, 2:38 AM MDTWind AdvisoryGJT17 hr
Apr 27, 2:27 PM MDTWinter Weather AdvisoryGJT55 hr
May 19, 2:50 PM MDTWind AdvisoryGJT29 hr
May 20, 2:00 PM MDTWind AdvisoryGJT30 hr
Jun 26, 2:42 PM MDTFire Weather WatchSLC23 hr
Jun 27, 1:45 PM MDTRed Flag WarningSLC32 hr
Jun 27, 1:57 PM MDTRed Flag WarningGJT30 hr
Jun 28, 2:17 PM MDTRed Flag WarningSLC32 hr
Jun 30, 3:16 PM MDTFlash Flood WatchGJT30 hr
Jul 1, 6:20 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 2, 8:48 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 8, 2:27 AM MDTRed Flag WarningSLC68 hr
Jul 8, 9:48 PM MDTRed Flag WarningGJT50 hr
Jul 14, 3:35 PM MDTFire Weather WatchSLC11 hr
Jul 15, 2:55 AM MDTRed Flag WarningSLC4 days
Jul 15, 3:45 AM MDTFire Weather WatchGJT11 hr
Jul 15, 2:58 PM MDTFire Weather WatchGJT24 hr
Jul 15, 2:58 PM MDTRed Flag WarningGJT30 hr
Jul 16, 6:17 PM MDTRed Flag WarningGJT27 hr
Jul 17, 12:12 PM MDTFire Weather WatchGJT10 hr
Jul 17, 2:48 PM MDTRed Flag WarningSLC30 hr
Jul 17, 9:42 PM MDTRed Flag WarningGJT24 hr
Jul 21, 9:14 PM MDTAreal Flood AdvisoryGJT2 hr
Jul 22, 5:14 PM MDTSpecial Weather StatementGJT46 min
Jul 28, 2:49 PM MDTRed Flag WarningSLC6 days
Aug 3, 3:40 AM MDTFlash Flood WatchGJT20 hr
Aug 3, 2:56 PM MDTFlash Flood WatchGJT29 hr
Aug 4, 2:25 PM MDTFlash Flood WatchGJT34 hr
Aug 4, 2:57 PM MDTAreal Flood AdvisoryGJT8 hr
Aug 4, 7:49 PM MDTSpecial Weather StatementGJT41 min
Aug 4, 8:33 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 5, 2:23 PM MDTFlash Flood WatchGJT32 hr
Aug 5, 10:00 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 8, 3:31 PM MDTAreal Flood AdvisoryGJT5 hr
Aug 17, 1:23 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 23, 3:07 AM MDTFlash Flood WatchGJT19 hr
Aug 24, 3:44 PM MDTSpecial Weather StatementGJT46 min
Sep 3, 1:51 PM MDTSpecial Weather StatementGJT39 min
Sep 13, 1:41 PM MDTSevere Thunderstorm WarningGJT34 min
Sep 22, 3:19 AM MDTHigh Wind WarningGJT20 hr
Sep 22, 3:19 AM MDTWind AdvisoryGJT20 hr
Sep 22, 10:24 AM MDTAreal Flood WarningSLC12 hr
Sep 22, 5:50 PM MDTFlash Flood WatchGJT8 hr
Sep 29, 9:49 AM MDTFlash Flood WatchGJT12 hr
Oct 16, 2:24 AM MDTWind AdvisoryGJT31 hr
Oct 19, 11:51 AM MDTFreeze WarningGJT21 hr
Nov 16, 4:30 AM MSTWinter Weather AdvisoryGJT44 hr
Nov 16, 9:18 PM MSTFreeze WarningGJT36 hr
Nov 19, 3:30 PM MSTWinter Storm WatchGJT23 hr
Nov 20, 3:55 AM MSTWinter Storm WarningGJT62 hr
Nov 25, 2:15 PM MSTWinter Storm WatchGJT14 hr
Nov 26, 4:29 AM MSTWinter Storm WarningGJT3 days
Nov 26, 4:29 AM MSTWinter Weather AdvisoryGJT3 days
Dec 14, 4:02 PM MSTWinter Storm WatchGJT12 hr
Dec 15, 3:45 AM MSTWinter Storm WarningGJT55 hr
Dec 21, 3:13 PM MSTWinter Storm WarningGJT41 hr
Dec 23, 2:53 AM MSTWinter Storm WatchGJT21 hr
Dec 23, 9:00 AM MSTDense Fog AdvisoryGJT3 hr
Dec 23, 2:26 PM MSTWinter Storm WarningGJT50 hr
Dec 31, 10:51 AM MSTWinter Weather AdvisoryGJT7 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

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.