Alert archive / Colorado / Broomfield County
Weather alerts in Broomfield County, Colorado, 2015
77 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Broomfield County and its neighbors
Each county as a circle sized by its count in 2015. Tap one for its archive.
- Alerts
- 77
- Warnings
- 17
- Watches
- 12
- Advisories
- 19
- Busiest month
- June20 alerts
- Busiest day
- June 5, 20156 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Broomfield County, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 4 | 3 | 25% | 0 | ||
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Denver/Boulder, CO: tornado warnings | 59 | 12 | 80% | 29 | 52% | 13 min |
| NWS Denver/Boulder, CO: severe thunderstorm warnings | 193 | 70 | 64% | 208 | 67% | 15 min |
| NWS Denver/Boulder, CO: flash flood warnings | 33 | 5 | 85% | 9 | 100% | 37 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 1, 6:16 PM MST | Winter Weather Advisory | BOU | 5 hr |
| Jan 7, 3:25 AM MST | Winter Weather Advisory | BOU | 6 hr |
| Jan 8, 3:08 PM MST | Winter Weather Advisory | BOU | 17 hr |
| Jan 31, 10:49 PM MST | Winter Weather Advisory | BOU | 8 hr |
| Feb 15, 3:56 AM MST | Winter Weather Advisory | BOU | 40 hr |
| Feb 19, 2:26 PM MST | Winter Storm Watch | BOU | 22 hr |
| Feb 20, 4:25 AM MST | Winter Storm Warning | BOU | 67 hr |
| Feb 21, 12:38 PM MST | Mesoscale Discussion | SPC | 5 hr |
| Feb 25, 4:18 AM MST | Winter Storm Warning | BOU | 24 hr |
| Feb 25, 4:18 AM MST | Winter Weather Advisory | BOU | 24 hr |
| Mar 3, 4:27 AM MST | Winter Weather Advisory | BOU | 25 hr |
| Mar 23, 2:40 PM MDT | Red Flag Warning | BOU | 27 hr |
| Mar 28, 4:55 AM MDT | Red Flag Warning | BOU | 13 hr |
| Apr 11, 9:10 PM MDT | Red Flag Warning | BOU | 22 hr |
| May 1, 12:31 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 3, 2:42 PM MDT | Special Weather Statement | BOU | 48 min |
| May 8, 11:08 AM MDT | Areal Flood Advisory | BOU | 60 hr |
| May 8, 9:24 PM MDT | Areal Flood Warning | BOU | 12 hr |
| May 9, 5:10 AM MDT | Flash Flood Watch | BOU | 15 hr |
| May 9, 5:15 AM MDT | Winter Storm Warning | BOU | 25 hr |
| May 9, 8:50 AM MDT | Areal Flood Warning | BOU | 12 hr |
| May 9, 9:09 AM MDT | Winter Storm Watch | BOU | 4 hr |
| May 10, 5:26 AM MDT | Frost Advisory | BOU | 26 hr |
| May 10, 5:56 AM MDT | Winter Storm Warning | BOU | 3 hr |
| May 23, 12:54 PM MDT | Tornado Watch | SPC | 6 hr |
| May 23, 1:38 PM MDT | Areal Flood Advisory | BOU | 2 hr |
| May 25, 5:16 PM MDT | Special Weather Statement | BOU | 29 min |
| May 28, 5:27 PM MDT | Special Weather Statement | BOU | 48 min |
| Jun 3, 12:34 PM MDT | Mesoscale Discussion | SPC | 86 min |
| Jun 3, 2:03 PM MDT | Tornado Watch | SPC | 7 hr |
| Jun 3, 5:29 PM MDT | Severe Thunderstorm Warning | BOU | 46 min |
| Jun 3, 7:14 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Jun 4, 2:20 PM MDT | Tornado Watch | SPC | 8 hr |
| Jun 4, 5:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jun 4, 8:20 PM MDT | Mesoscale Discussion | SPC | 115 min |
| Jun 4, 9:17 PM MDT | Severe Thunderstorm Warning | BOU | 43 min |
| Jun 4, 9:42 PM MDT | Severe Thunderstorm Warning | BOU | 33 min |
| Jun 5, 4:27 AM MDT | Flash Flood Watch | BOU | 18 hr |
| Jun 5, 12:49 PM MDT | Mesoscale Discussion | SPC | 86 min |
| Jun 5, 1:09 PM MDT | Tornado Watch | SPC | 6 hr |
| Jun 10, 11:41 AM MDT | Flash Flood Watch | BOU | 39 hr |
| Jun 16, 4:53 PM MDT | Mesoscale Discussion | SPC | 97 min |
| Jun 18, 8:53 PM MDT | Severe Thunderstorm Warning | BOU | 29 min |
| Jun 23, 4:09 PM MDT | Mesoscale Discussion | SPC | 96 min |
| Jun 24, 2:34 PM MDT | Mesoscale Discussion | SPC | 86 min |
| Jun 25, 2:30 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 25, 4:25 PM MDT | Mesoscale Discussion | SPC | 95 min |
| Jun 25, 9:30 PM MDT | Mesoscale Discussion | SPC | 30 min |
| Jul 1, 2:43 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 2, 7:10 PM MDT | Special Weather Statement | BOU | 35 min |
| Jul 15, 4:17 PM MDT | Special Weather Statement | BOU | 43 min |
| Jul 15, 4:47 PM MDT | Areal Flood Advisory | BOU | 88 min |
| Jul 16, 3:24 PM MDT | Special Weather Statement | BOU | 51 min |
| Jul 21, 12:46 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Aug 7, 2:12 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 16, 12:08 PM MDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 16, 2:53 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 17, 1:59 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 17, 2:32 PM MDT | Tornado Watch | SPC | 7 hr |
| Aug 17, 9:36 PM MDT | Special Weather Statement | BOU | 24 min |
| Sep 1, 4:38 PM MDT | Special Weather Statement | BOU | 22 min |
| Sep 29, 1:48 PM MDT | Mesoscale Discussion | SPC | 117 min |
| Oct 2, 2:09 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 23, 3:54 AM MDT | Frost Advisory | BOU | 28 hr |
| Oct 27, 3:13 AM MDT | Frost Advisory | BOU | 29 hr |
| Nov 10, 5:05 AM MST | Winter Weather Advisory | BOU | 30 hr |
| Nov 15, 3:36 PM MST | Blizzard Watch | BOU | 14 hr |
| Nov 16, 5:57 AM MST | Blizzard Warning | BOU | 32 hr |
| Nov 16, 5:57 AM MST | Winter Storm Warning | BOU | 26 hr |
| Nov 16, 5:57 AM MST | Winter Weather Advisory | BOU | 26 hr |
| Nov 25, 10:25 AM MST | Winter Weather Advisory | BOU | 42 hr |
| Nov 30, 3:38 PM MST | Winter Weather Advisory | BOU | 20 hr |
| Dec 14, 3:45 AM MST | Winter Weather Advisory | BOU | 37 hr |
| Dec 14, 3:12 PM MST | Winter Storm Warning | BOU | 26 hr |
| Dec 15, 2:55 AM MST | Mesoscale Discussion | SPC | 4 hr |
| Dec 17, 4:01 PM MST | High Wind Warning | BOU | 19 hr |
| Dec 23, 3:14 AM MST | Dense Fog Advisory | BOU | 7 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 | 4 |
| Severe Thunderstorm Watch | 1 |
| Tornado Watch | 5 |
| Mesoscale Discussion | 21 |
| Special Weather Statement | 8 |
| Flooding | |
| Areal Flood Warning | 2 |
| Flash Flood Watch | 3 |
| Areal Flood Advisory | 3 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 6 |
| Blizzard Watch | 1 |
| Winter Storm Watch | 2 |
| Winter Weather Advisory | 12 |
| Cold | |
| Frost Advisory | 3 |
| Wind and dust | |
| High Wind Warning | 1 |
| Fire | |
| Red Flag Warning | 3 |
| Fog and smoke | |
| Dense Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20142016
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.