Alert archive / Colorado / Grand County
Weather alerts in Grand County, Colorado, 2022
104 weather alerts in 2022, 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 2022. Tap one for its archive.
- Alerts
- 104
- Warnings
- 29
- Watches
- 15
- Advisories
- 57
- Busiest month
- July22 alerts
- Busiest day
- December 20, 20224 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Grand County, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 0 | 0 | ||||
| Flash flood warnings | 13 | 3 | 77% | 5 | 80% | 125 min |
Each office's whole area, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Denver/Boulder, CO: tornado warnings | 15 | 4 | 73% | 13 | 31% | 12 min |
| NWS Denver/Boulder, CO: severe thunderstorm warnings | 139 | 43 | 69% | 123 | 66% | 20 min |
| NWS Denver/Boulder, CO: flash flood warnings | 63 | 17 | 73% | 38 | 76% | 62 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 3, 2:37 PM MST | High Wind Warning | BOU | 26 hr |
| Jan 3, 2:37 PM MST | Winter Storm Watch | BOU | 24 hr |
| Jan 4, 4:49 AM MST | Winter Storm Warning | BOU | 61 hr |
| Jan 4, 2:54 PM MST | Winter Weather Advisory | BOU | 44 hr |
| Jan 6, 8:57 PM MST | Winter Weather Advisory | BOU | 8 hr |
| Jan 7, 8:02 PM MST | Winter Weather Advisory | BOU | 18 hr |
| Jan 31, 2:15 PM MST | Winter Weather Advisory | BOU | 54 hr |
| Feb 16, 3:32 AM MST | Winter Weather Advisory | BOU | 23 hr |
| Feb 20, 2:23 PM MST | Winter Weather Advisory | BOU | 40 hr |
| Feb 22, 3:03 AM MST | Winter Weather Advisory | BOU | 50 hr |
| Mar 4, 4:03 AM MST | Winter Weather Advisory | BOU | 64 hr |
| Mar 8, 3:05 AM MST | Winter Storm Warning | BOU | 48 hr |
| Mar 8, 3:05 AM MST | Winter Weather Advisory | BOU | 50 hr |
| Mar 16, 4:46 AM MDT | Winter Weather Advisory | BOU | 31 hr |
| Mar 17, 5:51 AM MDT | Winter Weather Advisory | BOU | 6 hr |
| Mar 28, 3:01 AM MDT | Winter Weather Advisory | BOU | 48 hr |
| Apr 4, 4:05 AM MDT | Winter Weather Advisory | BOU | 44 hr |
| Apr 11, 3:14 AM MDT | Winter Storm Warning | BOU | 55 hr |
| Apr 11, 3:14 AM MDT | Winter Weather Advisory | BOU | 69 hr |
| Apr 22, 3:18 AM MDT | Winter Weather Advisory | BOU | 45 hr |
| Apr 24, 8:07 AM MDT | Winter Weather Advisory | BOU | 22 hr |
| May 1, 9:19 PM MDT | Winter Weather Advisory | BOU | 10 hr |
| May 4, 7:14 AM MDT | Winter Weather Advisory | BOU | 13 hr |
| May 8, 1:31 PM MDT | High Wind Warning | BOU | 22 hr |
| May 9, 2:17 PM MDT | Fire Weather Watch | BOU | 24 hr |
| May 10, 2:09 PM MDT | Red Flag Warning | BOU | 31 hr |
| May 11, 4:40 AM MDT | Fire Weather Watch | BOU | 22 hr |
| May 18, 4:09 AM MDT | Winter Storm Watch | BOU | 34 hr |
| May 19, 3:55 AM MDT | Winter Storm Warning | BOU | 55 hr |
| May 19, 3:55 AM MDT | Winter Weather Advisory | BOU | 55 hr |
| May 20, 4:26 PM MDT | Mesoscale Discussion | SPC | 6 hr |
| May 24, 3:52 AM MDT | Winter Weather Advisory | BOU | 14 hr |
| May 29, 11:52 AM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 31, 2:54 AM MDT | Winter Weather Advisory | BOU | 33 hr |
| Jun 6, 2:43 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Jun 10, 3:41 PM MDT | Areal Flood Advisory | BOU | 51 hr |
| Jun 12, 6:38 PM MDT | Areal Flood Advisory | BOU | 60 hr |
| Jun 29, 5:57 PM MDT | Areal Flood Advisory | BOU | 2 hr |
| Jun 29, 7:34 PM MDT | Areal Flood Advisory | BOU | 79 min |
| Jul 2, 1:20 PM MDT | Areal Flood Advisory | BOU | 85 min |
| Jul 5, 12:52 PM MDT | Areal Flood Advisory | BOU | 76 min |
| Jul 5, 1:12 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Jul 5, 1:31 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Jul 7, 12:22 PM MDT | Areal Flood Advisory | BOU | 83 min |
| Jul 7, 12:42 PM MDT | Flash Flood Warning | BOU | 104 min |
| Jul 13, 4:19 PM MDT | Flash Flood Warning | BOU | 2 hr |
| Jul 13, 7:55 PM MDT | Areal Flood Advisory | BOU | 80 min |
| Jul 14, 2:10 PM MDT | Flash Flood Watch | BOU | 31 hr |
| Jul 14, 4:53 PM MDT | Areal Flood Advisory | BOU | 2 hr |
| Jul 15, 1:11 AM MDT | Flash Flood Watch | CYS | 20 hr |
| Jul 16, 1:00 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Jul 16, 1:15 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Jul 20, 3:21 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Jul 23, 2:32 PM MDT | Areal Flood Advisory | BOU | 107 min |
| Jul 23, 6:47 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Jul 24, 2:25 AM MDT | Flash Flood Watch | BOU | 18 hr |
| Jul 27, 2:43 PM MDT | Flash Flood Watch | BOU | 31 hr |
| Jul 28, 2:22 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Jul 28, 3:46 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Jul 29, 12:27 PM MDT | Flash Flood Warning | BOU | 2 hr |
| Jul 31, 1:02 PM MDT | Flash Flood Warning | BOU | 2 hr |
| Aug 1, 3:25 PM MDT | Areal Flood Advisory | BOU | 50 min |
| Aug 2, 3:49 PM MDT | Areal Flood Advisory | BOU | 86 min |
| Aug 5, 2:53 PM MDT | Areal Flood Advisory | BOU | 112 min |
| Aug 11, 3:33 PM MDT | Areal Flood Advisory | BOU | 117 min |
| Aug 13, 4:56 PM MDT | Special Weather Statement | BOU | 34 min |
| Aug 13, 5:35 PM MDT | Areal Flood Advisory | BOU | 115 min |
| Aug 14, 1:37 PM MDT | Flood Watch | BOU | 30 hr |
| Aug 20, 4:55 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Aug 21, 3:10 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Aug 22, 2:54 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Aug 22, 3:14 PM MDT | Flash Flood Warning | BOU | 4 hr |
| Aug 23, 4:22 PM MDT | Flash Flood Warning | BOU | 3 hr |
| Aug 24, 3:16 PM MDT | Areal Flood Advisory | BOU | 77 min |
| Aug 28, 2:51 PM MDT | Areal Flood Advisory | BOU | 3 hr |
| Aug 28, 3:48 PM MDT | Flash Flood Warning | BOU | 2 hr |
| Sep 20, 10:23 AM MDT | Flood Watch | BOU | 41 hr |
| Oct 20, 2:18 PM MDT | Red Flag Warning | BOU | 28 hr |
| Oct 22, 2:23 AM MDT | Winter Storm Warning | BOU | 49 hr |
| Oct 22, 2:23 AM MDT | Winter Weather Advisory | BOU | 49 hr |
| Oct 26, 2:30 AM MDT | Winter Weather Advisory | BOU | 34 hr |
| Nov 2, 1:57 PM MDT | Winter Weather Advisory | BOU | 40 hr |
| Nov 4, 1:08 PM MDT | High Wind Warning | BOU | 29 hr |
| Nov 4, 2:07 PM MDT | Winter Weather Advisory | BOU | 46 hr |
| Nov 8, 2:12 PM MST | Winter Weather Advisory | BOU | 46 hr |
| Nov 16, 1:55 AM MST | Winter Weather Advisory | BOU | 55 hr |
| Nov 27, 12:49 AM MST | Winter Storm Watch | BOU | 13 hr |
| Nov 27, 1:34 PM MST | Winter Storm Warning | BOU | 51 hr |
| Nov 28, 2:07 AM MST | Winter Weather Advisory | BOU | 39 hr |
| Nov 30, 2:40 PM MST | Winter Storm Watch | BOU | 12 hr |
| Dec 1, 2:44 AM MST | Winter Storm Warning | BOU | 38 hr |
| Dec 4, 2:19 PM MST | Winter Weather Advisory | BOU | 51 hr |
| Dec 7, 1:23 PM MST | Winter Weather Advisory | BOU | 24 hr |
| Dec 11, 3:56 AM MST | Winter Weather Advisory | BOU | 4 days |
| Dec 19, 4:07 AM MST | Wind Chill Watch | BOU | 35 hr |
| Dec 20, 3:52 AM MST | Winter Storm Watch | BOU | 11 hr |
| Dec 20, 2:59 PM MST | Wind Chill Warning | BOU | 68 hr |
| Dec 20, 2:59 PM MST | Winter Storm Warning | BOU | 42 hr |
| Dec 20, 2:59 PM MST | Winter Weather Advisory | BOU | 42 hr |
| Dec 26, 1:30 PM MST | High Wind Watch | BOU | 14 hr |
| Dec 26, 1:41 PM MST | Winter Weather Advisory | BOU | 66 hr |
| Dec 27, 3:05 AM MST | High Wind Warning | BOU | 17 hr |
| Dec 29, 1:53 PM MST | Winter Storm Warning | BOU | 69 hr |
| Dec 30, 1:21 PM MST | Winter Weather Advisory | BOU | 46 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 | |
| Mesoscale Discussion | 2 |
| Special Weather Statement | 1 |
| Flooding | |
| Flash Flood Warning | 13 |
| Flash Flood Watch | 4 |
| Flood Watch | 2 |
| Areal Flood Advisory | 23 |
| Winter | |
| Winter Storm Warning | 9 |
| Winter Storm Watch | 5 |
| Winter Weather Advisory | 34 |
| Cold | |
| Wind Chill Warning | 1 |
| Wind Chill Watch | 1 |
| Wind and dust | |
| High Wind Warning | 4 |
| High Wind Watch | 1 |
| Fire | |
| Red Flag Warning | 2 |
| Fire Weather Watch | 2 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe 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.