Alert archive / Colorado / Jefferson County
Weather alerts in Jefferson County, Colorado, 2010
120 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Jefferson County and its neighbors
Each county as a circle sized by its count in 2010. Tap one for its archive.
- Alerts
- 120
- Warnings
- 40
- Watches
- 28
- Advisories
- 38
- Busiest month
- June21 alerts
- Busiest day
- June 11, 20107 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 Jefferson County in 2010 had a tornado report inside them.
Jefferson County, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 6 | 4 | 33% | 10 | 30% | 22 min |
| Flash flood warnings | 1 | 0 | 100% | 0 |
Each office's whole area, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Denver/Boulder, CO: tornado warnings | 80 | 21 | 74% | 36 | 69% | 14 min |
| NWS Denver/Boulder, CO: severe thunderstorm warnings | 153 | 68 | 56% | 268 | 54% | 23 min |
| NWS Denver/Boulder, CO: flash flood warnings | 22 | 3 | 86% | 6 | 100% | 50 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 5, 3:33 PM MST | Winter Weather Advisory | BOU | 35 hr |
| Jan 23, 10:17 AM MST | Winter Weather Advisory | BOU | 32 hr |
| Feb 13, 8:10 AM MST | Winter Weather Advisory | BOU | 27 hr |
| Feb 19, 2:26 PM MST | Winter Weather Advisory | BOU | 62 hr |
| Mar 14, 5:47 AM MDT | Winter Weather Advisory | BOU | 20 hr |
| Mar 14, 10:22 AM MDT | Winter Storm Warning | BOU | 15 hr |
| Mar 17, 2:56 PM MDT | Winter Storm Watch | BOU | 22 hr |
| Mar 18, 6:19 AM MDT | Winter Storm Warning | BOU | 42 hr |
| Mar 22, 2:58 PM MDT | Winter Storm Warning | BOU | 44 hr |
| Mar 22, 2:58 PM MDT | Winter Weather Advisory | BOU | 44 hr |
| Mar 23, 6:21 PM MDT | Mesoscale Discussion | SPC | 6 hr |
| Mar 25, 4:23 AM MDT | Winter Storm Watch | BOU | 25 hr |
| Mar 26, 5:08 AM MDT | Winter Storm Warning | BOU | 15 hr |
| Apr 3, 4:40 AM MDT | Winter Weather Advisory | BOU | 19 hr |
| Apr 3, 6:37 AM MDT | Red Flag Warning | BOU | 13 hr |
| Apr 4, 3:01 AM MDT | Fire Weather Watch | BOU | 27 hr |
| Apr 5, 5:48 AM MDT | Red Flag Warning | BOU | 14 hr |
| Apr 5, 7:02 AM MDT | Winter Weather Advisory | BOU | 45 hr |
| Apr 6, 1:34 PM MDT | Winter Storm Warning | BOU | 18 hr |
| Apr 22, 11:19 AM MDT | Winter Storm Watch | BOU | 18 hr |
| Apr 22, 11:19 AM MDT | Winter Storm Warning | BOU | 46 hr |
| Apr 22, 12:30 PM MDT | Tornado Watch | SPC | 8 hr |
| Apr 24, 9:00 AM MDT | Winter Weather Advisory | BOU | 6 hr |
| Apr 24, 4:01 PM MDT | Frost Advisory | BOU | 16 hr |
| Apr 28, 3:58 PM MDT | Winter Weather Advisory | BOU | 26 hr |
| May 4, 4:12 AM MDT | High Wind Warning | BOU | 8 hr |
| May 9, 3:04 PM MDT | Winter Storm Watch | BOU | 45 hr |
| May 11, 4:23 AM MDT | Winter Weather Advisory | BOU | 24 hr |
| May 12, 2:59 PM MDT | Freeze Warning | BOU | 7 hr |
| May 14, 2:52 PM MDT | Winter Weather Advisory | BOU | 17 hr |
| May 24, 9:58 AM MDT | High Wind Warning | BOU | 7 hr |
| May 26, 1:49 PM MDT | Tornado Watch | SPC | 7 hr |
| Jun 6, 1:48 PM MDT | Mesoscale Discussion | SPC | 117 min |
| Jun 6, 2:24 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 8, 10:20 AM MDT | Flash Flood Watch | BOU | 8 hr |
| Jun 9, 2:39 PM MDT | Tornado Watch | SPC | 6 hr |
| Jun 10, 3:17 PM MDT | Flood Watch | BOU | 3 days |
| Jun 10, 6:11 PM MDT | Severe Thunderstorm Warning | BOU | 49 min |
| Jun 11, 1:09 PM MDT | Mesoscale Discussion | SPC | 96 min |
| Jun 11, 2:43 PM MDT | Severe Thunderstorm Warning | BOU | 32 min |
| Jun 11, 3:14 PM MDT | Severe Thunderstorm Warning | BOU | 31 min |
| Jun 11, 3:26 PM MDT | Areal Flood Advisory | BOU | 79 min |
| Jun 11, 3:44 PM MDT | Severe Thunderstorm Warning | BOU | 31 min |
| Jun 11, 3:51 PM MDT | Tornado Warning | BOU | 39 min |
| Jun 12, 12:17 AM MDT | Areal Flood Advisory | BOU | 88 min |
| Jun 15, 1:48 PM MDT | High Wind Watch | BOU | 14 hr |
| Jun 16, 4:02 AM MDT | High Wind Warning | BOU | 29 hr |
| Jun 17, 3:52 AM MDT | Red Flag Warning | BOU | 16 hr |
| Jun 20, 1:30 PM MDT | Tornado Watch | SPC | 7 hr |
| Jun 20, 4:23 PM MDT | Mesoscale Discussion | SPC | 67 min |
| Jun 22, 4:41 AM MDT | Red Flag Warning | BOU | 16 hr |
| Jun 26, 5:26 PM MDT | Special Weather Statement | BOU | 34 min |
| Jun 27, 3:49 PM MDT | Special Weather Statement | BOU | 41 min |
| Jul 2, 12:19 PM MDT | Mesoscale Discussion | SPC | 56 min |
| Jul 3, 2:08 PM MDT | Red Flag Warning | BOU | 5 hr |
| Jul 4, 12:39 PM MDT | Tornado Watch | SPC | 8 hr |
| Jul 4, 6:31 PM MDT | Severe Thunderstorm Warning | BOU | 29 min |
| Jul 8, 1:31 PM MDT | Mesoscale Discussion | SPC | 59 min |
| Jul 9, 2:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jul 11, 3:44 PM MDT | Special Weather Statement | BOU | 46 min |
| Jul 22, 1:59 PM MDT | Areal Flood Advisory | BOU | 91 min |
| Jul 27, 1:37 PM MDT | Areal Flood Advisory | BOU | 56 min |
| Jul 28, 2:25 PM MDT | Areal Flood Advisory | BOU | 80 min |
| Jul 30, 4:24 AM MDT | Flash Flood Watch | BOU | 17 hr |
| Aug 1, 4:36 AM MDT | Flash Flood Watch | BOU | 16 hr |
| Aug 1, 2:59 PM MDT | Areal Flood Advisory | BOU | 91 min |
| Aug 1, 3:13 PM MDT | Flash Flood Warning | BOU | 2 hr |
| Aug 4, 3:28 PM MDT | Areal Flood Advisory | BOU | 92 min |
| Aug 9, 3:10 PM MDT | Areal Flood Advisory | BOU | 95 min |
| Aug 15, 4:01 PM MDT | Mesoscale Discussion | SPC | 29 min |
| Aug 15, 11:51 PM MDT | Areal Flood Advisory | BOU | 84 min |
| Aug 16, 2:34 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 16, 5:44 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Aug 19, 8:14 PM MDT | Severe Thunderstorm Warning | BOU | 23 min |
| Aug 23, 3:00 PM MDT | Special Weather Statement | BOU | 30 min |
| Sep 4, 3:46 AM MDT | Fire Weather Watch | BOU | 11 hr |
| Sep 4, 3:08 PM MDT | Red Flag Warning | BOU | 30 hr |
| Sep 8, 2:57 PM MDT | Fire Weather Watch | BOU | 24 hr |
| Sep 8, 2:57 PM MDT | Red Flag Warning | BOU | 51 hr |
| Sep 14, 2:20 AM MDT | Fire Weather Watch | BOU | 13 hr |
| Sep 19, 4:24 AM MDT | Fire Weather Watch | BOU | 10 hr |
| Sep 19, 2:03 PM MDT | Red Flag Warning | BOU | 31 hr |
| Oct 12, 4:07 AM MDT | Frost Advisory | BOU | 29 hr |
| Oct 18, 3:56 PM MDT | Frost Advisory | BOU | 17 hr |
| Oct 23, 4:08 AM MDT | Winter Storm Watch | BOU | 24 hr |
| Oct 24, 3:50 AM MDT | High Wind Watch | BOU | 8 hr |
| Oct 24, 4:03 AM MDT | Winter Storm Warning | BOU | 60 hr |
| Oct 25, 4:26 AM MDT | Freeze Warning | BOU | 27 hr |
| Oct 26, 1:29 PM MDT | Red Flag Warning | BOU | 5 hr |
| Oct 26, 3:07 PM MDT | Fire Weather Watch | BOU | 13 hr |
| Oct 26, 3:57 PM MDT | Winter Weather Advisory | BOU | 17 hr |
| Oct 26, 7:20 PM MDT | Freeze Warning | BOU | 14 hr |
| Oct 27, 4:09 AM MDT | Red Flag Warning | BOU | 15 hr |
| Oct 27, 3:14 PM MDT | Freeze Warning | BOU | 18 hr |
| Oct 29, 9:12 AM MDT | Red Flag Warning | BOU | 9 hr |
| Nov 9, 3:37 AM MST | Winter Weather Advisory | BOU | 19 hr |
| Nov 14, 3:50 AM MST | Winter Weather Advisory | BOU | 40 hr |
| Nov 15, 5:16 AM MST | High Wind Watch | BOU | 15 hr |
| Nov 16, 8:07 AM MST | Winter Weather Advisory | BOU | 7 hr |
| Nov 16, 3:08 PM MST | Winter Storm Warning | BOU | 14 hr |
| Nov 20, 4:34 AM MST | Winter Weather Advisory | BOU | 58 hr |
| Nov 20, 10:49 PM MST | Dense Fog Advisory | BOU | 11 hr |
| Nov 22, 9:48 PM MST | Winter Storm Warning | BOU | 32 hr |
| Nov 23, 8:41 PM MST | Winter Weather Advisory | BOU | 20 hr |
| Nov 28, 10:09 AM MST | Winter Weather Advisory | BOU | 21 hr |
| Dec 2, 3:45 AM MST | High Wind Watch | BOU | 12 hr |
| Dec 2, 3:33 PM MST | High Wind Warning | BOU | 24 hr |
| Dec 10, 4:54 AM MST | Winter Weather Advisory | BOU | 5 hr |
| Dec 10, 9:55 AM MST | Winter Storm Warning | BOU | 25 hr |
| Dec 11, 11:09 AM MST | Winter Weather Advisory | BOU | 6 hr |
| Dec 14, 3:16 PM MST | Winter Weather Advisory | BOU | 32 hr |
| Dec 18, 4:13 AM MST | Winter Storm Watch | BOU | 6 hr |
| Dec 18, 4:13 AM MST | Winter Storm Warning | BOU | 4 days |
| Dec 18, 10:14 AM MST | Winter Weather Advisory | BOU | 17 hr |
| Dec 29, 3:29 AM MST | Winter Storm Watch | BOU | 13 hr |
| Dec 29, 3:27 PM MST | Winter Storm Warning | BOU | 44 hr |
| Dec 29, 3:27 PM MST | Winter Weather Advisory | BOU | 47 hr |
| Dec 30, 12:53 PM MST | Mesoscale Discussion | SPC | 5 hr |
| Dec 31, 2:45 PM MST | Wind Chill Warning | BOU | 19 hr |
| Dec 31, 2:45 PM MST | Wind Chill Advisory | BOU | 19 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.