Alert archive / Colorado / Jefferson County

Weather alerts in Jefferson County, Colorado, 2013

136 weather alerts in 2013, 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 2013. Tap one for its archive.

Alerts
136
Warnings
51
Watches
23
Advisories
43
Busiest month
September30 alerts
Busiest day
September 13, 20139 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Jefferson County, 2013

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings5260%20%
Flash flood warnings12467%1100%39 min

Each office's whole area, 2013

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Denver/Boulder, CO: tornado warnings61985%1675%18 min
NWS Denver/Boulder, CO: severe thunderstorm warnings2276571%17361%18 min
NWS Denver/Boulder, CO: flash flood warnings851978%5082%148 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 23, 3:07 PM MSTRed Flag WarningBOU25 hr
Jan 28, 3:37 AM MSTWinter Storm WatchBOU24 hr
Jan 29, 3:10 AM MSTWinter Storm WarningBOU60 hr
Feb 8, 3:18 PM MSTWinter Weather AdvisoryBOU38 hr
Feb 17, 1:05 PM MSTRed Flag WarningBOU5 hr
Feb 20, 4:17 AM MSTWinter Weather AdvisoryBOU30 hr
Feb 22, 3:27 PM MSTWinter Storm WatchBOU24 hr
Feb 23, 3:41 PM MSTWinter Storm WarningBOU29 hr
Feb 23, 3:41 PM MSTWinter Weather AdvisoryBOU25 hr
Feb 24, 5:44 AM MSTMesoscale DiscussionSPC4 hr
Mar 3, 4:11 AM MSTWinter Weather AdvisoryBOU32 hr
Mar 7, 4:21 AM MSTWinter Storm WatchBOU24 hr
Mar 8, 4:14 AM MSTWinter Storm WarningBOU37 hr
Mar 9, 6:33 AM MSTMesoscale DiscussionSPC4 hr
Mar 16, 3:38 PM MDTWinter Weather AdvisoryBOU26 hr
Mar 19, 3:49 AM MDTRed Flag WarningBOU14 hr
Mar 22, 6:20 AM MDTWinter Storm WarningBOU36 hr
Mar 22, 4:28 PM MDTWinter Weather AdvisoryBOU26 hr
Apr 7, 4:15 AM MDTWinter Storm WatchBOU36 hr
Apr 8, 11:19 AM MDTWinter Storm WarningBOU27 hr
Apr 8, 4:26 PM MDTWinter Weather AdvisoryBOU35 hr
Apr 11, 3:32 AM MDTWinter Weather AdvisoryBOU14 hr
Apr 12, 3:55 PM MDTWinter Weather AdvisoryBOU43 hr
Apr 14, 5:15 AM MDTWinter Storm WatchBOU26 hr
Apr 15, 4:51 AM MDTWinter Storm WarningBOU23 hr
Apr 15, 4:51 AM MDTWinter Weather AdvisoryBOU23 hr
Apr 16, 3:52 PM MDTWinter Weather AdvisoryBOU35 hr
Apr 21, 2:55 PM MDTWinter Storm WatchBOU15 hr
Apr 22, 5:46 AM MDTWinter Weather AdvisoryBOU27 hr
Apr 22, 9:20 AM MDTWinter Storm WarningBOU20 hr
Apr 29, 3:05 PM MDTWinter Storm WatchBOU21 hr
Apr 30, 4:05 AM MDTWinter Storm WarningBOU40 hr
May 8, 3:55 AM MDTWinter Weather AdvisoryBOU36 hr
May 26, 2:49 PM MDTMesoscale DiscussionSPC56 min
Jun 9, 3:13 PM MDTFire Weather WatchBOU21 hr
Jun 9, 3:13 PM MDTFire Weather WatchBOU21 hr
Jun 10, 12:10 PM MDTRed Flag WarningBOU9 hr
Jun 10, 12:10 PM MDTRed Flag WarningBOU33 hr
Jun 12, 1:52 PM MDTRed Flag WarningBOU31 hr
Jun 13, 1:14 PM MDTMesoscale DiscussionSPC91 min
Jun 16, 6:55 PM MDTSpecial Weather StatementBOU50 min
Jun 17, 2:21 PM MDTSevere Thunderstorm WatchSPC9 hr
Jun 21, 3:35 PM MDTRed Flag WarningBOU28 hr
Jun 23, 4:56 PM MDTSpecial Weather StatementBOU19 min
Jun 24, 5:01 AM MDTRed Flag WarningBOU15 hr
Jun 24, 2:32 PM MDTRed Flag WarningBOU27 hr
Jun 28, 1:54 PM MDTMesoscale DiscussionSPC3 hr
Jun 28, 9:32 PM MDTSevere Thunderstorm WarningBOU28 min
Jun 28, 9:52 PM MDTSevere Thunderstorm WarningBOU23 min
Jun 29, 12:44 PM MDTMesoscale DiscussionSPC3 hr
Jul 1, 6:23 PM MDTSpecial Weather StatementBOU37 min
Jul 3, 7:11 PM MDTSpecial Weather StatementBOU34 min
Jul 10, 12:21 PM MDTSpecial Weather StatementBOU39 min
Jul 10, 1:29 PM MDTSevere Thunderstorm WatchSPC10 hr
Jul 13, 4:58 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 13, 5:20 PM MDTAreal Flood AdvisoryBOU115 min
Jul 13, 5:52 PM MDTFlash Flood WarningBOU3 hr
Jul 14, 4:45 AM MDTFlash Flood WatchBOU19 hr
Jul 14, 9:38 PM MDTAreal Flood AdvisoryBOU112 min
Jul 15, 1:34 PM MDTAreal Flood AdvisoryBOU116 min
Jul 15, 2:27 PM MDTAreal Flood AdvisoryBOU78 min
Jul 19, 4:19 AM MDTFlash Flood WatchBOU12 hr
Jul 27, 2:05 PM MDTMesoscale DiscussionSPC115 min
Aug 3, 2:35 PM MDTTornado WatchSPC6 hr
Aug 3, 6:29 PM MDTAreal Flood AdvisoryBOU2 hr
Aug 9, 3:36 PM MDTSpecial Weather StatementBOU39 min
Aug 9, 3:43 PM MDTSevere Thunderstorm WarningBOU47 min
Aug 12, 2:35 PM MDTMesoscale DiscussionSPC2 hr
Aug 12, 6:58 PM MDTSpecial Weather StatementBOU47 min
Aug 13, 2:05 PM MDTMesoscale DiscussionSPC115 min
Aug 22, 5:45 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 22, 5:45 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 22, 5:45 PM MDTSevere Thunderstorm WarningBOU30 min
Aug 22, 6:06 PM MDTFlash Flood WarningBOU114 min
Aug 23, 3:19 PM MDTSpecial Weather StatementBOU56 min
Aug 23, 3:41 PM MDTSpecial Weather StatementBOU34 min
Aug 23, 6:22 PM MDTSevere Thunderstorm WarningBOU38 min
Aug 27, 2:50 PM MDTSpecial Weather StatementBOU40 min
Sep 4, 4:09 PM MDTAreal Flood AdvisoryBOU2 hr
Sep 9, 3:11 PM MDTAreal Flood AdvisoryBOU94 min
Sep 11, 3:10 PM MDTAreal Flood AdvisoryBOU3 hr
Sep 11, 4:06 PM MDTAreal Flood AdvisoryBOU114 min
Sep 11, 9:46 PM MDTFlash Flood WarningBOU3 hr
Sep 11, 11:16 PM MDTFlash Flood Warning EmergencyBOU5 hr
Sep 12, 5:00 AM MDTFlash Flood WatchBOU40 hr
Sep 12, 8:28 AM MDTAreal Flood WarningBOU12 hr
Sep 12, 3:29 PM MDTFlash Flood Warning EmergencyBOU8 hr
Sep 12, 7:23 PM MDTFlash Flood WarningBOU6 hr
Sep 12, 7:35 PM MDTAreal Flood WarningBOU12 hr
Sep 12, 10:52 PM MDTFlash Flood Warning EmergencyBOU5 hr
Sep 12, 11:38 PM MDTRiver Flood WarningBOU8 hr
Sep 12, 11:58 PM MDTFlash Flood Warning EmergencyBOU6 hr
Sep 13, 12:07 AM MDTRiver Flood WarningBOU24 hr
Sep 13, 12:09 AM MDTFlash Flood WarningBOU6 hr
Sep 13, 7:34 AM MDTAreal Flood WarningBOU24 hr
Sep 13, 5:20 PM MDTAreal Flood AdvisoryBOU85 min
Sep 14, 4:30 AM MDTFlash Flood WatchBOU40 hr
Sep 14, 7:50 AM MDTAreal Flood WarningBOU12 hr
Sep 14, 12:50 PM MDTFlash Flood WarningBOU3 hr
Sep 14, 4:39 PM MDTFlash Flood WarningBOU3 hr
Sep 14, 5:57 PM MDTFlash Flood WarningBOU3 hr
Sep 15, 9:10 AM MDTAreal Flood WarningBOU12 hr
Sep 15, 12:08 PM MDTAreal Flood WarningBOU9 hr
Sep 15, 9:22 PM MDTAreal Flood AdvisoryBOU12 hr
Sep 16, 3:55 AM MDTFlash Flood WatchBOU15 hr
Sep 16, 10:18 AM MDTAreal Flood AdvisoryBOU23 hr
Sep 17, 10:06 AM MDTAreal Flood AdvisoryBOU24 hr
Sep 27, 4:13 AM MDTFrost AdvisoryBOU28 hr
Oct 3, 10:27 AM MDTFreeze WatchBOU20 hr
Oct 3, 3:14 PM MDTWinter Weather AdvisoryBOU27 hr
Oct 4, 6:06 AM MDTFreeze WarningBOU27 hr
Oct 10, 3:42 AM MDTWinter Weather AdvisoryBOU32 hr
Oct 10, 3:49 AM MDTHigh Wind WatchBOU11 hr
Oct 10, 2:55 PM MDTHigh Wind WarningBOU18 hr
Oct 14, 3:44 PM MDTFreeze WarningBOU17 hr
Oct 15, 9:05 AM MDTFreeze WarningBOU24 hr
Oct 16, 3:42 PM MDTWinter Weather AdvisoryBOU41 hr
Oct 21, 2:05 AM MDTDense Fog AdvisoryBOU7 hr
Oct 28, 4:52 PM MDTWinter Weather AdvisoryBOU16 hr
Oct 31, 8:57 PM MDTHigh Wind WarningBOU5 hr
Nov 4, 3:50 AM MSTWinter Weather AdvisoryBOU31 hr
Nov 15, 4:43 AM MSTHigh Wind WatchBOU31 hr
Nov 15, 3:46 PM MSTWinter Weather AdvisoryBOU43 hr
Nov 16, 11:16 AM MSTHigh Wind WarningBOU28 hr
Nov 20, 3:07 PM MSTWinter Weather AdvisoryBOU25 hr
Dec 1, 3:56 AM MSTHigh Wind WatchBOU11 hr
Dec 1, 2:26 PM MSTHigh Wind WarningBOU28 hr
Dec 2, 4:16 AM MSTWinter Storm WatchBOU11 hr
Dec 2, 4:16 AM MSTWinter Storm WarningBOU59 hr
Dec 2, 3:42 PM MSTWinter Storm WatchBOU13 hr
Dec 4, 11:49 AM MSTWinter Weather AdvisoryBOU3 hr
Dec 10, 5:20 PM MSTHigh Wind WarningBOU4 hr
Dec 10, 8:03 PM MSTAreal Flood AdvisoryBOU12 hr
Dec 21, 3:26 AM MSTWinter Weather AdvisoryBOU12 hr
Dec 21, 5:15 AM MSTDense Fog AdvisoryBOU5 hr
Dec 22, 2:37 PM MSTWinter Weather AdvisoryBOU20 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 archive20122014

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.