Alert archive / Colorado / Adams County

Weather alerts in Adams County, Colorado, 2015

170 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Adams County and its neighbors

Each county as a circle sized by its count in 2015. Tap one for its archive.

Alerts
170
Warnings
60
Watches
24
Advisories
39
Busiest month
June72 alerts
Busiest day
June 5, 201519 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 10 tornado warnings covering Adams County in 2015 had a tornado report inside them; 1 of 2 tornado reports fell inside a warning, on average 5 minutes after it went out.

Adams County, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10190%250%5 min
Severe thunderstorm warnings291162%967%23 min
Flash flood warnings4175%0

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Denver/Boulder, CO: tornado warnings591280%2952%13 min
NWS Denver/Boulder, CO: severe thunderstorm warnings1937064%20867%15 min
NWS Denver/Boulder, CO: flash flood warnings33585%9100%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.

IssuedProductOfficeLasted
Jan 1, 6:16 PM MSTWinter Weather AdvisoryBOU5 hr
Jan 2, 3:37 PM MSTWinter Weather AdvisoryBOU29 hr
Jan 7, 3:25 AM MSTWinter Weather AdvisoryBOU6 hr
Jan 8, 3:08 PM MSTWinter Weather AdvisoryBOU17 hr
Jan 31, 10:49 PM MSTWinter Weather AdvisoryBOU8 hr
Feb 15, 3:56 AM MSTWinter Weather AdvisoryBOU40 hr
Feb 19, 2:26 PM MSTWinter Storm WatchBOU22 hr
Feb 20, 4:25 AM MSTWinter Storm WarningBOU67 hr
Feb 20, 12:53 PM MSTWinter Weather AdvisoryBOU58 hr
Feb 21, 12:38 PM MSTMesoscale DiscussionSPC5 hr
Feb 25, 4:18 AM MSTWinter Weather AdvisoryBOU24 hr
Mar 3, 4:27 AM MSTWinter Weather AdvisoryBOU25 hr
Mar 16, 3:39 AM MDTRed Flag WarningBOU14 hr
Mar 22, 2:56 PM MDTFire Weather WatchBOU24 hr
Mar 23, 2:40 PM MDTRed Flag WarningBOU27 hr
Apr 13, 5:25 AM MDTFire Weather WatchBOU9 hr
Apr 13, 2:45 PM MDTRed Flag WarningBOU29 hr
Apr 17, 11:58 AM MDTMesoscale DiscussionSPC92 min
Apr 26, 4:29 AM MDTAreal Flood AdvisoryBOU3 hr
May 1, 12:31 PM MDTMesoscale DiscussionSPC2 hr
May 4, 7:09 PM MDTAreal Flood AdvisoryBOU111 min
May 8, 11:08 AM MDTAreal Flood AdvisoryBOU60 hr
May 9, 5:10 AM MDTFlash Flood WatchBOU15 hr
May 9, 5:15 AM MDTWinter Storm WarningBOU25 hr
May 9, 6:53 AM MDTAreal Flood AdvisoryBOU3 hr
May 9, 7:51 AM MDTFlash Flood WarningBOU3 hr
May 9, 8:50 AM MDTAreal Flood WarningBOU12 hr
May 9, 9:09 AM MDTWinter Storm WatchBOU4 hr
May 9, 10:52 AM MDTAreal Flood WarningBOU9 hr
May 9, 5:16 PM MDTMesoscale DiscussionSPC119 min
May 9, 7:49 PM MDTAreal Flood WarningBOU18 hr
May 10, 5:26 AM MDTFrost AdvisoryBOU26 hr
May 10, 5:56 AM MDTWinter Storm WarningBOU3 hr
May 10, 1:04 PM MDTAreal Flood WarningBOU24 hr
May 15, 12:49 PM MDTSevere Thunderstorm WarningBOU41 min
May 15, 1:21 PM MDTSevere Thunderstorm WarningBOU27 min
May 15, 1:35 PM MDTTornado WarningBOU25 min
May 15, 1:58 PM MDTTornado WarningBOU37 min
May 19, 6:52 AM MDTAreal Flood AdvisoryBOU8 hr
May 19, 9:47 AM MDTRiver Flood WarningBOU20 hr
May 23, 5:41 AM MDTFlash Flood WatchBOU18 hr
May 23, 12:27 PM MDTMesoscale DiscussionSPC2 hr
May 23, 12:54 PM MDTTornado WatchSPC6 hr
May 23, 1:38 PM MDTAreal Flood AdvisoryBOU2 hr
May 23, 2:36 PM MDTSevere Thunderstorm WarningBOU24 min
May 23, 4:11 PM MDTMesoscale DiscussionSPC2 hr
May 24, 4:44 AM MDTFlash Flood WatchBOU14 hr
May 24, 1:23 PM MDTAreal Flood AdvisoryBOU3 hr
May 24, 1:25 PM MDTSpecial Weather StatementBOU35 min
May 24, 2:43 PM MDTAreal Flood AdvisoryBOU3 hr
May 28, 1:18 PM MDTSevere Thunderstorm WatchSPC7 hr
May 31, 2:27 PM MDTSpecial Weather StatementBOU48 min
May 31, 2:45 PM MDTSpecial Weather StatementBOU45 min
May 31, 2:50 PM MDTMesoscale DiscussionSPC115 min
Jun 1, 3:44 PM MDTSpecial Weather StatementBOU46 min
Jun 3, 12:34 PM MDTMesoscale DiscussionSPC86 min
Jun 3, 2:03 PM MDTTornado WatchSPC7 hr
Jun 3, 4:59 PM MDTSevere Thunderstorm WarningBOU30 min
Jun 3, 5:24 PM MDTSevere Thunderstorm WarningBOU38 min
Jun 3, 5:29 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 3, 7:14 PM MDTMesoscale DiscussionSPC61 min
Jun 3, 7:45 PM MDTSevere Thunderstorm WarningBOU45 min
Jun 3, 8:29 PM MDTSevere Thunderstorm WarningBOU61 min
Jun 3, 8:59 PM MDTSevere Thunderstorm WatchSPC5 hr
Jun 3, 9:15 PM MDTSevere Thunderstorm WarningBOU34 min
Jun 4, 1:53 PM MDTMesoscale DiscussionSPC97 min
Jun 4, 2:20 PM MDTTornado WatchSPC8 hr
Jun 4, 4:28 PM MDTSevere Thunderstorm WarningBOU24 min
Jun 4, 4:47 PM MDTTornado WarningBOU13 min
Jun 4, 5:03 PM MDTSevere Thunderstorm WarningBOU27 min
Jun 4, 5:22 PM MDTMesoscale DiscussionSPC113 min
Jun 4, 8:20 PM MDTMesoscale DiscussionSPC115 min
Jun 4, 9:17 PM MDTSevere Thunderstorm WarningBOU43 min
Jun 4, 9:19 PM MDTSevere Thunderstorm WarningBOU26 min
Jun 4, 9:42 PM MDTSevere Thunderstorm WarningBOU33 min
Jun 4, 9:47 PM MDTAreal Flood AdvisoryBOU3 hr
Jun 4, 10:39 PM MDTSevere Thunderstorm WarningBOU22 min
Jun 5, 12:48 AM MDTAreal Flood AdvisoryBOU117 min
Jun 5, 1:45 AM MDTSevere Thunderstorm WarningBOU30 min
Jun 5, 4:27 AM MDTFlash Flood WatchBOU18 hr
Jun 5, 6:12 AM MDTRiver Flood WarningBOU38 hr
Jun 5, 12:49 PM MDTMesoscale DiscussionSPC86 min
Jun 5, 1:09 PM MDTTornado WatchSPC6 hr
Jun 5, 1:25 PM MDTAreal Flood AdvisoryBOU3 hr
Jun 5, 1:48 PM MDTTornado WarningBOU42 min
Jun 5, 3:04 PM MDTTornado WarningBOU26 min
Jun 5, 3:27 PM MDTTornado WarningBOU33 min
Jun 5, 4:03 PM MDTSevere Thunderstorm WarningBOU42 min
Jun 5, 4:31 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 5, 4:58 PM MDTTornado WarningBOU32 min
Jun 5, 9:11 PM MDTAreal Flood AdvisoryBOU94 min
Jun 6, 10:14 AM MDTRiver Flood AdvisoryBOU30 hr
Jun 6, 2:14 PM MDTMesoscale DiscussionSPC91 min
Jun 6, 4:25 PM MDTSevere Thunderstorm WatchSPC5 hr
Jun 6, 6:55 PM MDTMesoscale DiscussionSPC95 min
Jun 6, 9:33 PM MDTMesoscale DiscussionSPC57 min
Jun 7, 1:36 PM MDTMesoscale DiscussionSPC114 min
Jun 7, 5:35 PM MDTSpecial Weather StatementBOU40 min
Jun 7, 5:55 PM MDTAreal Flood AdvisoryBOU95 min
Jun 10, 11:17 AM MDTRiver Flood AdvisoryBOU52 hr
Jun 10, 11:41 AM MDTFlash Flood WatchBOU39 hr
Jun 11, 10:35 AM MDTRiver Flood WarningBOU43 hr
Jun 11, 6:43 PM MDTAreal Flood AdvisoryBOU3 hr
Jun 13, 6:35 PM MDTSevere Thunderstorm WarningBOU25 min
Jun 13, 7:01 PM MDTFlash Flood WarningBOU2 hr
Jun 16, 2:44 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 16, 4:53 PM MDTMesoscale DiscussionSPC97 min
Jun 16, 6:43 PM MDTSevere Thunderstorm WarningBOU32 min
Jun 16, 9:28 PM MDTMesoscale DiscussionSPC62 min
Jun 18, 8:53 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 23, 4:09 PM MDTMesoscale DiscussionSPC96 min
Jun 24, 2:34 PM MDTMesoscale DiscussionSPC86 min
Jun 24, 4:45 PM MDTSevere Thunderstorm WarningBOU45 min
Jun 24, 5:08 PM MDTAreal Flood AdvisoryBOU52 min
Jun 24, 5:09 PM MDTTornado WarningBOU21 min
Jun 24, 5:22 PM MDTFlash Flood WarningBOU113 min
Jun 24, 7:19 PM MDTFlash Flood WarningBOU3 hr
Jun 24, 8:22 PM MDTRiver Flood WarningBOU21 hr
Jun 25, 2:30 PM MDTSevere Thunderstorm WatchSPC8 hr
Jun 25, 4:14 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 25, 4:25 PM MDTMesoscale DiscussionSPC95 min
Jun 25, 4:56 PM MDTSevere Thunderstorm WarningBOU49 min
Jun 25, 6:39 PM MDTAreal Flood AdvisoryBOU111 min
Jun 25, 9:30 PM MDTMesoscale DiscussionSPC30 min
Jun 28, 6:14 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 28, 7:15 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 1, 2:43 PM MDTMesoscale DiscussionSPC3 hr
Jul 8, 4:53 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 9, 8:13 PM MDTAreal Flood AdvisoryBOU2 hr
Jul 15, 4:47 PM MDTAreal Flood AdvisoryBOU88 min
Jul 15, 5:54 PM MDTSpecial Weather StatementBOU36 min
Jul 18, 3:29 PM MDTMesoscale DiscussionSPC2 hr
Jul 18, 3:45 PM MDTSpecial Weather StatementBOU45 min
Jul 18, 4:34 PM MDTSpecial Weather StatementBOU41 min
Jul 21, 12:46 PM MDTMesoscale DiscussionSPC119 min
Jul 21, 3:50 PM MDTFlash Flood WatchBOU4 hr
Jul 21, 4:11 PM MDTSevere Thunderstorm WarningBOU34 min
Jul 26, 1:07 PM MDTSevere Thunderstorm WatchSPC9 hr
Aug 7, 2:12 PM MDTMesoscale DiscussionSPC3 hr
Aug 7, 3:05 PM MDTSevere Thunderstorm WatchSPC8 hr
Aug 7, 5:50 PM MDTTornado WarningBOU40 min
Aug 7, 6:33 PM MDTSevere Thunderstorm WarningBOU42 min
Aug 11, 4:04 PM MDTTornado WarningBOU26 min
Aug 16, 12:08 PM MDTMesoscale DiscussionSPC3 hr
Aug 16, 2:53 PM MDTMesoscale DiscussionSPC2 hr
Aug 17, 1:59 PM MDTMesoscale DiscussionSPC2 hr
Aug 17, 2:32 PM MDTTornado WatchSPC7 hr
Aug 17, 3:56 PM MDTSevere Thunderstorm WarningBOU49 min
Aug 17, 4:28 PM MDTSevere Thunderstorm WarningBOU47 min
Aug 17, 4:41 PM MDTMesoscale DiscussionSPC94 min
Aug 31, 4:42 PM MDTSpecial Weather StatementBOU48 min
Sep 7, 4:46 PM MDTMesoscale DiscussionSPC119 min
Sep 29, 1:48 PM MDTMesoscale DiscussionSPC117 min
Oct 2, 2:09 PM MDTMesoscale DiscussionSPC2 hr
Oct 6, 6:45 AM MDTDense Fog AdvisoryBOU3 hr
Oct 23, 3:54 AM MDTFrost AdvisoryBOU28 hr
Oct 27, 3:13 AM MDTFrost AdvisoryBOU29 hr
Nov 9, 3:05 PM MSTBlizzard WatchBOU14 hr
Nov 10, 5:05 AM MSTBlizzard WarningBOU30 hr
Nov 10, 5:05 AM MSTWinter Weather AdvisoryBOU30 hr
Nov 11, 1:27 AM MSTMesoscale DiscussionSPC6 hr
Nov 15, 3:36 PM MSTBlizzard WatchBOU14 hr
Nov 16, 5:57 AM MSTBlizzard WarningBOU32 hr
Nov 16, 8:05 PM MSTMesoscale DiscussionSPC4 hr
Nov 17, 9:27 AM MSTMesoscale DiscussionSPC4 hr
Nov 25, 10:25 AM MSTWinter Weather AdvisoryBOU42 hr
Dec 14, 3:45 AM MSTWinter Weather AdvisoryBOU37 hr
Dec 14, 3:12 PM MSTWinter Storm WarningBOU26 hr
Dec 15, 2:55 AM MSTMesoscale DiscussionSPC4 hr
Dec 23, 3:14 AM MSTDense Fog AdvisoryBOU7 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 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.