Alert archive / Colorado / Grand County
Weather alerts in Grand County, Colorado, 2012
67 weather alerts in 2012, 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 2012. Tap one for its archive.
- Alerts
- 67
- Warnings
- 32
- Watches
- 10
- Advisories
- 21
- Busiest month
- June14 alerts
- Busiest day
- January 20, 20125 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, 2012
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 1 | 0 | 100% | 0 | ||
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2012
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Denver/Boulder, CO: tornado warnings | 24 | 7 | 71% | 17 | 47% | 23 min |
| NWS Denver/Boulder, CO: severe thunderstorm warnings | 95 | 39 | 59% | 128 | 58% | 20 min |
| NWS Denver/Boulder, CO: flash flood warnings | 26 | 7 | 73% | 12 | 50% | 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 16, 2:36 PM MST | High Wind Watch | BOU | 36 hr |
| Jan 17, 9:57 AM MST | High Wind Warning | BOU | 50 hr |
| Jan 18, 2:49 PM MST | Blizzard Warning | BOU | 18 hr |
| Jan 18, 2:49 PM MST | Winter Storm Warning | BOU | 20 hr |
| Jan 19, 8:12 PM MST | Winter Weather Advisory | BOU | 15 hr |
| Jan 20, 4:31 AM MST | Winter Storm Watch | BOU | 7 hr |
| Jan 20, 11:26 AM MST | Winter Storm Warning | BOU | 48 hr |
| Jan 20, 11:26 AM MST | Winter Weather Advisory | BOU | 43 hr |
| Jan 20, 11:30 AM MST | High Wind Warning | BOU | 28 hr |
| Jan 26, 4:05 PM MST | Winter Weather Advisory | BOU | 13 hr |
| Feb 2, 5:07 AM MST | Winter Storm Warning | BOU | 47 hr |
| Feb 2, 5:07 AM MST | Winter Weather Advisory | BOU | 7 hr |
| Feb 20, 4:25 AM MST | High Wind Watch | BOU | 24 hr |
| Feb 21, 4:17 AM MST | High Wind Warning | BOU | 48 hr |
| Feb 21, 4:22 AM MST | Winter Weather Advisory | BOU | 17 hr |
| Feb 21, 8:56 PM MST | Winter Storm Warning | BOU | 38 hr |
| Feb 21, 8:56 PM MST | Winter Weather Advisory | BOU | 26 hr |
| Feb 28, 3:35 AM MST | Winter Weather Advisory | BOU | 20 hr |
| Feb 28, 9:29 AM MST | High Wind Warning | BOU | 24 hr |
| Feb 29, 4:01 AM MST | Winter Weather Advisory | BOU | 11 hr |
| Feb 29, 3:12 PM MST | Winter Storm Warning | BOU | 38 hr |
| Feb 29, 3:12 PM MST | Winter Weather Advisory | BOU | 38 hr |
| Mar 30, 4:16 PM MDT | Fire Weather Watch | BOU | 24 hr |
| Mar 31, 4:14 PM MDT | Red Flag Warning | BOU | 27 hr |
| Apr 2, 3:34 PM MDT | Winter Weather Advisory | BOU | 26 hr |
| Apr 4, 3:29 PM MDT | Red Flag Warning | BOU | 28 hr |
| Apr 5, 3:38 PM MDT | Red Flag Warning | BOU | 28 hr |
| Apr 10, 4:09 PM MDT | Red Flag Warning | BOU | 28 hr |
| Apr 13, 3:35 AM MDT | Winter Storm Watch | BOU | 26 hr |
| Apr 14, 5:35 AM MDT | Winter Storm Warning | BOU | 24 hr |
| Apr 14, 5:35 AM MDT | Winter Weather Advisory | BOU | 36 hr |
| May 4, 2:57 AM MDT | Red Flag Warning | BOU | 17 hr |
| May 4, 4:12 PM MDT | Red Flag Warning | BOU | 26 hr |
| May 6, 8:24 PM MDT | Winter Weather Advisory | BOU | 18 hr |
| Jun 3, 1:03 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 7, 4:25 PM MDT | Fire Weather Watch | BOU | 23 hr |
| Jun 8, 3:03 PM MDT | Red Flag Warning | BOU | 55 hr |
| Jun 13, 2:57 PM MDT | Red Flag Warning | BOU | 6 hr |
| Jun 16, 3:58 AM MDT | Fire Weather Watch | BOU | 10 hr |
| Jun 16, 2:02 PM MDT | Red Flag Warning | BOU | 30 hr |
| Jun 17, 4:37 AM MDT | Red Flag Warning | BOU | 40 hr |
| Jun 18, 4:59 AM MDT | Fire Weather Watch | BOU | 10 hr |
| Jun 18, 3:12 PM MDT | Red Flag Warning | BOU | 30 hr |
| Jun 20, 4:31 PM MDT | Fire Weather Watch | BOU | 23 hr |
| Jun 21, 3:16 PM MDT | Red Flag Warning | BOU | 54 hr |
| Jun 23, 3:42 PM MDT | Red Flag Warning | BOU | 30 hr |
| Jun 24, 2:54 PM MDT | Red Flag Warning | BOU | 30 hr |
| Jun 25, 3:29 PM MDT | Red Flag Warning | BOU | 29 hr |
| Jul 5, 1:07 PM MDT | Severe Thunderstorm Warning | BOU | 27 min |
| Jul 23, 3:08 PM MDT | Areal Flood Advisory | BOU | 82 min |
| Jul 30, 2:30 PM MDT | Special Weather Statement | BOU | 30 min |
| Sep 3, 10:46 AM MDT | Special Weather Statement | BOU | 59 min |
| Sep 3, 3:28 PM MDT | Special Weather Statement | BOU | 47 min |
| Oct 3, 11:26 AM MDT | Red Flag Warning | BOU | 7 hr |
| Nov 9, 4:02 AM MST | Winter Weather Advisory | BOU | 49 hr |
| Nov 30, 4:57 AM MST | High Wind Watch | BOU | 9 hr |
| Nov 30, 1:53 PM MST | High Wind Warning | BOU | 15 hr |
| Dec 7, 4:20 PM MST | High Wind Warning | BOU | 25 hr |
| Dec 7, 9:25 PM MST | Winter Weather Advisory | BOU | 17 hr |
| Dec 8, 2:44 PM MST | Winter Storm Warning | BOU | 11 hr |
| Dec 8, 8:25 PM MST | Winter Weather Advisory | BOU | 12 hr |
| Dec 15, 3:32 PM MST | Winter Weather Advisory | BOU | 23 hr |
| Dec 16, 2:47 PM MST | Winter Storm Warning | BOU | 38 hr |
| Dec 16, 2:47 PM MST | Winter Weather Advisory | BOU | 38 hr |
| Dec 18, 1:56 PM MST | Winter Weather Advisory | BOU | 25 hr |
| Dec 23, 3:28 PM MST | Winter Weather Advisory | BOU | 38 hr |
| Dec 26, 11:01 AM MST | Winter Weather Advisory | BOU | 34 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 | 1 |
| Mesoscale Discussion | 1 |
| Special Weather Statement | 3 |
| Flooding | |
| Areal Flood Advisory | 1 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 8 |
| Winter Storm Watch | 2 |
| Winter Weather Advisory | 20 |
| Wind and dust | |
| High Wind Warning | 6 |
| High Wind Watch | 3 |
| Fire | |
| Red Flag Warning | 16 |
| Fire Weather Watch | 5 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20112013
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.