Alert archive / Colorado / Denver County

Weather alerts in Denver County, Colorado, 2013

110 weather alerts in 2013, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Denver County and its neighbors

Each county as a circle sized by its count in 2013. Tap one for its archive.

Alerts
110
Warnings
32
Watches
12
Advisories
27
Busiest month
September33 alerts
Busiest day
September 12, 201311 alerts

Over time

By month

Warning verification

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

1 of 1 tornado warnings covering Denver County in 2013 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 13 minutes after it went out.

Denver County, 2013

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings110%1100%13 min
Severe thunderstorm warnings7271%367%11 min
Flash flood warnings12192%0

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
Feb 17, 1:05 PM MSTRed Flag WarningBOU5 hr
Feb 19, 4:19 AM MSTWinter Storm WatchBOU30 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 24, 5:44 AM MSTMesoscale DiscussionSPC4 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 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 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 22, 5:46 AM MDTWinter Weather AdvisoryBOU27 hr
Apr 30, 12:12 PM MDTWinter Weather AdvisoryBOU39 hr
May 26, 2:49 PM MDTMesoscale DiscussionSPC56 min
Jun 10, 2:58 PM MDTSpecial Weather StatementBOU47 min
Jun 10, 7:06 PM MDTSpecial Weather StatementBOU39 min
Jun 13, 1:14 PM MDTMesoscale DiscussionSPC91 min
Jun 15, 1:53 PM MDTMesoscale DiscussionSPC97 min
Jun 15, 5:57 PM MDTMesoscale DiscussionSPC63 min
Jun 17, 2:21 PM MDTSevere Thunderstorm WatchSPC9 hr
Jun 18, 1:07 PM MDTMesoscale DiscussionSPC113 min
Jun 18, 2:09 PM MDTTornado WarningBOU36 min
Jun 18, 5:11 PM MDTMesoscale DiscussionSPC94 min
Jun 18, 7:52 PM MDTMesoscale DiscussionSPC83 min
Jun 23, 3:48 PM MDTMesoscale DiscussionSPC87 min
Jun 23, 4:29 PM MDTSpecial Weather StatementBOU31 min
Jun 23, 4:40 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 23, 7:19 PM MDTMesoscale DiscussionSPC56 min
Jun 23, 9:07 PM MDTSpecial Weather StatementBOU23 min
Jun 28, 1:54 PM MDTMesoscale DiscussionSPC3 hr
Jun 28, 8:10 PM MDTMesoscale DiscussionSPC95 min
Jun 29, 12:44 PM MDTMesoscale DiscussionSPC3 hr
Jul 10, 1:09 PM MDTMesoscale DiscussionSPC66 min
Jul 10, 1:29 PM MDTSevere Thunderstorm WatchSPC10 hr
Jul 13, 4:28 PM MDTSpecial Weather StatementBOU47 min
Jul 13, 5:20 PM MDTAreal Flood AdvisoryBOU115 min
Jul 15, 12:25 PM MDTSpecial Weather StatementBOU50 min
Jul 15, 12:31 PM MDTAreal Flood AdvisoryBOU119 min
Jul 15, 1:34 PM MDTAreal Flood AdvisoryBOU116 min
Jul 20, 4:43 PM MDTSpecial Weather StatementBOU32 min
Jul 20, 7:06 PM MDTSevere Thunderstorm WarningBOU24 min
Jul 27, 2:05 PM MDTMesoscale DiscussionSPC115 min
Jul 28, 4:20 PM MDTMesoscale DiscussionSPC2 hr
Aug 3, 1:50 PM MDTMesoscale DiscussionSPC85 min
Aug 3, 2:35 PM MDTTornado WatchSPC6 hr
Aug 3, 3:03 PM MDTSpecial Weather StatementBOU42 min
Aug 3, 5:21 PM MDTMesoscale DiscussionSPC54 min
Aug 3, 6:24 PM MDTSevere Thunderstorm WarningBOU36 min
Aug 3, 6:29 PM MDTAreal Flood AdvisoryBOU2 hr
Aug 3, 7:31 PM MDTAreal Flood AdvisoryBOU89 min
Aug 8, 6:50 PM MDTSpecial Weather StatementBOU55 min
Aug 8, 7:13 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 8, 7:37 PM MDTFlash Flood WarningBOU3 hr
Aug 10, 6:46 PM MDTSpecial Weather StatementBOU14 min
Aug 10, 6:48 PM MDTSpecial Weather StatementBOU27 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 15, 6:30 PM MDTSpecial Weather StatementBOU30 min
Aug 22, 5:45 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 22, 5:45 PM MDTSevere Thunderstorm WarningBOU30 min
Aug 22, 6:26 PM MDTSevere Thunderstorm WarningBOU49 min
Aug 22, 6:58 PM MDTAreal Flood AdvisoryBOU2 hr
Aug 23, 5:31 PM MDTSpecial Weather StatementBOU44 min
Sep 4, 4:45 PM MDTSpecial Weather StatementBOU45 min
Sep 9, 2:57 PM MDTSpecial Weather StatementBOU48 min
Sep 9, 3:53 PM MDTAreal Flood AdvisoryBOU67 min
Sep 9, 4:09 PM MDTMesoscale DiscussionSPC3 hr
Sep 10, 5:04 PM MDTAreal Flood AdvisoryBOU56 min
Sep 11, 4:06 PM MDTAreal Flood AdvisoryBOU114 min
Sep 11, 9:47 PM MDTAreal Flood AdvisoryBOU3 hr
Sep 11, 10:01 PM MDTFlash Flood WarningBOU3 hr
Sep 12, 12:59 AM MDTAreal Flood WarningBOU3 hr
Sep 12, 5:00 AM MDTFlash Flood WatchBOU40 hr
Sep 12, 5:24 AM MDTAreal Flood AdvisoryBOU3 hr
Sep 12, 6:01 AM MDTFlash Flood WarningBOU3 hr
Sep 12, 8:28 AM MDTAreal Flood WarningBOU12 hr
Sep 12, 9:02 AM MDTFlash Flood WarningBOU3 hr
Sep 12, 9:12 AM MDTFlash Flood WarningBOU3 hr
Sep 12, 12:14 PM MDTFlash Flood WarningBOU3 hr
Sep 12, 5:04 PM MDTFlash Flood WarningBOU4 hr
Sep 12, 7:35 PM MDTAreal Flood WarningBOU12 hr
Sep 12, 9:35 PM 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, 3:38 PM MDTSevere Thunderstorm WarningBOU37 min
Sep 14, 3:53 PM MDTFlash Flood WarningBOU3 hr
Sep 14, 4:23 PM MDTFlash Flood WarningBOU3 hr
Sep 14, 7:00 PM MDTFlash Flood WarningBOU3 hr
Sep 15, 9:10 AM MDTAreal Flood WarningBOU12 hr
Sep 15, 12:32 PM MDTFlash Flood WarningBOU4 hr
Sep 15, 9:22 PM MDTAreal Flood AdvisoryBOU12 hr
Sep 22, 5:32 PM MDTSpecial Weather StatementBOU43 min
Sep 22, 5:42 PM MDTSevere Thunderstorm WarningBOU33 min
Sep 22, 6:04 PM MDTSevere Thunderstorm WarningBOU41 min
Sep 27, 4:13 AM MDTFrost AdvisoryBOU28 hr
Oct 3, 10:27 AM MDTFreeze WatchBOU20 hr
Oct 4, 6:06 AM MDTFreeze WarningBOU27 hr
Oct 21, 2:05 AM MDTDense Fog AdvisoryBOU7 hr
Nov 20, 3:07 PM MSTWinter Weather AdvisoryBOU25 hr
Dec 2, 3:42 PM MSTWinter Storm WatchBOU13 hr
Dec 3, 4:52 AM MSTWinter Weather AdvisoryBOU31 hr
Dec 21, 5:15 AM MSTDense Fog AdvisoryBOU5 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.