Alert archive / Utah / Grand County

Weather alerts in Grand County, Utah, 2010

134 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Grand County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Alerts
134
Warnings
39
Watches
31
Advisories
57
Busiest month
August22 alerts
Busiest day
October 6, 20108 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 1 tornado warnings covering Grand County in 2010 had a tornado report inside them.

Grand County, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10100%0
Severe thunderstorm warnings8275%367%16 min
Flash flood warnings7271%250%27 min

Each office's whole area, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Grand Junction, CO: tornado warnings10100%0
NWS Grand Junction, CO: severe thunderstorm warnings49884%3824%21 min
NWS Grand Junction, CO: flash flood warnings20385%1040%60 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 16, 3:24 PM MSTWinter Storm WatchGJT24 hr
Jan 17, 3:29 PM MSTWinter Storm WarningGJT48 hr
Jan 17, 3:29 PM MSTWinter Weather AdvisoryGJT48 hr
Jan 19, 3:30 PM MSTWinter Weather AdvisoryGJT27 hr
Jan 19, 10:05 PM MSTWinter Storm WarningGJT18 hr
Jan 20, 3:31 AM MSTBlizzard WatchGJT13 hr
Jan 20, 4:09 PM MSTBlizzard WarningGJT42 hr
Jan 20, 4:09 PM MSTWinter Storm WarningGJT5 days
Jan 26, 3:55 PM MSTWinter Storm WarningGJT44 hr
Jan 26, 3:55 PM MSTWinter Weather AdvisoryGJT44 hr
Jan 28, 3:06 PM MSTDense Fog AdvisoryGJT22 hr
Jan 29, 5:08 PM MSTDense Fog AdvisoryGJT17 hr
Feb 4, 7:22 AM MSTDense Fog AdvisoryGJT5 hr
Feb 4, 3:09 PM MSTDense Fog AdvisoryGJT21 hr
Feb 5, 2:43 PM MSTWinter Storm WatchGJT13 hr
Feb 6, 3:43 AM MSTWinter Storm WarningGJT54 hr
Feb 6, 3:43 AM MSTWinter Weather AdvisoryGJT54 hr
Feb 7, 8:23 PM MSTDense Fog AdvisoryGJT13 hr
Feb 16, 7:21 AM MSTDense Fog AdvisoryGJT4 hr
Feb 16, 6:31 PM MSTDense Fog AdvisoryGJT17 hr
Feb 18, 4:06 AM MSTWinter Weather AdvisoryGJT4 days
Feb 18, 9:27 PM MSTWinter Storm WarningGJT4 days
Mar 3, 3:18 PM MSTWinter Weather AdvisoryGJT63 hr
Mar 6, 4:47 AM MSTWinter Storm WarningGJT61 hr
Mar 6, 4:47 AM MSTWinter Weather AdvisoryGJT61 hr
Mar 9, 3:27 AM MSTWinter Weather AdvisoryGJT45 hr
Mar 13, 3:36 AM MSTWinter Storm WarningGJT37 hr
Mar 15, 3:32 AM MDTDense Fog AdvisoryGJT7 hr
Mar 25, 4:53 AM MDTWinter Weather AdvisoryGJT55 hr
Mar 29, 3:54 PM MDTWind AdvisoryGJT28 hr
Mar 30, 8:00 PM MDTWind AdvisoryGJT25 hr
Mar 31, 4:16 AM MDTWinter Weather AdvisoryGJT48 hr
Apr 2, 3:34 PM MDTWinter Weather AdvisoryGJT41 hr
Apr 4, 4:24 AM MDTWinter Storm WatchGJT19 hr
Apr 4, 4:38 AM MDTWind AdvisoryGJT46 hr
Apr 4, 10:59 PM MDTWinter Weather AdvisoryGJT53 hr
Apr 11, 3:16 PM MDTWind AdvisoryGJT33 hr
Apr 20, 3:09 PM MDTWind AdvisoryGJT27 hr
Apr 21, 12:24 PM MDTMesoscale DiscussionSPC96 min
Apr 26, 3:07 PM MDTHigh Wind WatchGJT23 hr
Apr 27, 2:21 PM MDTHigh Wind WarningGJT34 hr
Apr 27, 9:17 PM MDTWinter Weather AdvisoryGJT3 days
Apr 28, 2:56 PM MDTFreeze WatchGJT14 hr
Apr 29, 4:38 AM MDTFreeze WarningGJT28 hr
Apr 29, 3:04 PM MDTFreeze WatchGJT21 hr
Apr 30, 12:27 PM MDTFreeze WarningGJT21 hr
May 1, 2:31 PM MDTWinter Weather AdvisoryGJT38 hr
May 2, 2:29 PM MDTFreeze WarningGJT18 hr
May 6, 3:23 PM MDTFreeze WarningGJT18 hr
May 11, 4:41 AM MDTWind AdvisoryGJT15 hr
May 20, 3:03 PM MDTHigh Wind WatchGJT13 hr
May 20, 3:03 PM MDTWind AdvisoryGJT30 hr
May 21, 4:21 AM MDTHigh Wind WarningGJT41 hr
May 21, 4:21 AM MDTWind AdvisoryGJT41 hr
May 22, 3:32 PM MDTWind AdvisoryGJT32 hr
May 27, 8:09 PM MDTWind AdvisoryGJT25 hr
Jun 7, 2:20 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 13, 6:29 PM MDTAreal Flood AdvisoryGJT6 hr
Jun 16, 3:05 AM MDTWind AdvisoryGJT18 hr
Jul 21, 9:29 AM MDTFlash Flood WatchGJT12 hr
Jul 22, 5:58 AM MDTFlash Flood WatchGJT15 hr
Jul 26, 5:16 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 26, 6:29 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 26, 6:43 PM MDTFlash Flood WarningGJT3 hr
Jul 27, 3:00 AM MDTFlash Flood WatchGJT18 hr
Jul 27, 4:01 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 27, 4:42 PM MDTAreal Flood AdvisoryGJT3 hr
Jul 27, 6:15 PM MDTAreal Flood AdvisoryGJT2 hr
Jul 28, 4:11 AM MDTFlash Flood WatchGJT17 hr
Jul 28, 1:40 PM MDTFlash Flood WatchGJT31 hr
Jul 30, 3:41 AM MDTFlash Flood WatchGJT17 hr
Jul 30, 3:02 PM MDTFlash Flood WatchGJT30 hr
Jul 31, 12:57 PM MDTFlash Flood WarningGJT3 hr
Jul 31, 3:03 PM MDTFlash Flood WatchGJT3 days
Jul 31, 4:24 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 1, 12:53 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 2, 1:58 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 2, 3:52 PM MDTAreal Flood AdvisoryGJT75 min
Aug 2, 4:46 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 2, 6:57 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 4, 3:16 AM MDTFlash Flood WatchGJT18 hr
Aug 4, 11:55 AM MDTSevere Thunderstorm WarningGJT50 min
Aug 4, 12:13 PM MDTAreal Flood AdvisoryGJT3 hr
Aug 4, 8:33 PM MDTFlash Flood WarningGJT3 hr
Aug 4, 9:43 PM MDTFlash Flood WarningGJT3 hr
Aug 5, 4:38 AM MDTFlash Flood WatchGJT17 hr
Aug 16, 3:45 PM MDTSevere Thunderstorm WarningGJT45 min
Aug 17, 2:34 PM MDTFlash Flood WarningGJT3 hr
Aug 17, 5:31 PM MDTFlash Flood WarningGJT4 hr
Aug 19, 4:29 AM MDTFlash Flood WatchGJT17 hr
Aug 19, 11:59 AM MDTMesoscale DiscussionSPC2 hr
Aug 19, 1:37 PM MDTSevere Thunderstorm WarningGJT23 min
Aug 19, 1:50 PM MDTFlash Flood WarningGJT3 hr
Aug 19, 1:59 PM MDTSevere Thunderstorm WarningGJT46 min
Aug 22, 4:47 AM MDTFlash Flood WatchGJT16 hr
Aug 29, 4:33 AM MDTWind AdvisoryGJT16 hr
Aug 29, 1:13 PM MDTMesoscale DiscussionSPC2 hr
Sep 9, 4:57 AM MDTWind AdvisoryGJT16 hr
Sep 21, 2:34 PM MDTFlash Flood WatchGJT37 hr
Sep 22, 8:47 PM MDTAreal Flood AdvisoryGJT3 hr
Oct 5, 3:25 PM MDTFlash Flood WatchGJT29 hr
Oct 6, 9:38 AM MDTMesoscale DiscussionSPC2 hr
Oct 6, 10:29 AM MDTTornado WatchSPC7 hr
Oct 6, 2:32 PM MDTSevere Thunderstorm WarningGJT43 min
Oct 6, 3:13 PM MDTSevere Thunderstorm WarningGJT47 min
Oct 6, 3:15 PM MDTSevere Thunderstorm WarningGJT45 min
Oct 6, 3:43 PM MDTMesoscale DiscussionSPC92 min
Oct 6, 3:59 PM MDTSevere Thunderstorm WarningGJT46 min
Oct 6, 4:14 PM MDTTornado WarningGJT16 min
Oct 7, 1:18 PM MDTMesoscale DiscussionSPC117 min
Oct 7, 1:53 PM MDTSevere Thunderstorm WatchSPC6 hr
Oct 7, 6:01 PM MDTMesoscale DiscussionSPC59 min
Oct 23, 6:09 AM MDTWinter Storm WatchGJT32 hr
Oct 23, 3:00 PM MDTFreeze WatchGJT24 hr
Oct 23, 3:16 PM MDTWinter Storm WarningGJT69 hr
Oct 24, 2:34 PM MDTFreeze WarningGJT42 hr
Oct 26, 12:00 PM MDTFreeze WarningGJT21 hr
Nov 7, 3:21 PM MSTWinter Weather AdvisoryGJT54 hr
Nov 10, 3:34 AM MSTWinter Weather AdvisoryGJT44 hr
Nov 19, 3:08 PM MSTWinter Storm WatchGJT3 hr
Nov 19, 5:56 PM MSTWinter Storm WarningGJT3 days
Nov 20, 8:50 AM MSTWind AdvisoryGJT9 hr
Nov 21, 10:09 AM MSTWind AdvisoryGJT10 hr
Nov 22, 4:29 AM MSTBlizzard WatchGJT23 hr
Nov 22, 3:10 PM MSTHigh Wind WatchGJT13 hr
Nov 22, 3:13 PM MSTBlizzard WarningGJT54 hr
Nov 23, 3:41 AM MSTHigh Wind WarningGJT25 hr
Nov 27, 3:59 AM MSTWinter Weather AdvisoryGJT63 hr
Dec 14, 2:30 PM MSTWinter Weather AdvisoryGJT52 hr
Dec 17, 4:06 AM MSTWinter Weather AdvisoryGJT3 days
Dec 18, 4:04 AM MSTWinter Storm WarningGJT6 days
Dec 27, 3:13 PM MSTWinter Storm WatchGJT24 hr
Dec 28, 3:26 PM MSTWinter Storm WarningGJT67 hr
Dec 28, 3:26 PM MSTWinter Weather AdvisoryGJT18 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 archive20092011

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.