Alert archive / Colorado / Adams County

Weather alerts in Adams County, Colorado, 2018

162 weather alerts in 2018, 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 2018. Tap one for its archive.

Alerts
162
Warnings
63
Watches
24
Advisories
25
Busiest month
July38 alerts
Busiest day
June 19, 201813 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 4 tornado warnings covering Adams County in 2018 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 11 minutes after it went out.

Adams County, 2018

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings4175%1100%11 min
Severe thunderstorm warnings391464%2095%13 min
Flash flood warnings110%0

Each office's whole area, 2018

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Denver/Boulder, CO: tornado warnings521179%3653%12 min
NWS Denver/Boulder, CO: severe thunderstorm warnings32211465%36975%20 min
NWS Denver/Boulder, CO: flash flood warnings13377%1479%32 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 15, 6:46 AM MSTWinter Weather AdvisoryBOU6 hr
Jan 19, 1:54 PM MSTWinter Storm WatchBOU16 hr
Jan 20, 5:24 AM MSTWinter Storm WarningBOU36 hr
Feb 9, 5:37 PM MSTDense Fog AdvisoryBOU3 hr
Feb 18, 2:01 PM MSTWinter Weather AdvisoryBOU34 hr
Mar 2, 3:51 AM MSTRed Flag WarningBOU14 hr
Mar 2, 6:04 PM MSTFire Weather WatchBOU21 hr
Mar 3, 3:17 PM MSTFire Weather WatchBOU5 hr
Mar 3, 3:17 PM MSTFire Weather WatchBOU19 hr
Mar 3, 3:17 PM MSTRed Flag WarningBOU28 hr
Mar 4, 5:22 AM MSTHigh Wind WatchBOU9 hr
Mar 4, 5:22 AM MSTHigh Wind WarningBOU36 hr
Mar 4, 9:49 AM MSTRed Flag WarningBOU32 hr
Mar 17, 2:40 PM MDTWinter Weather AdvisoryBOU37 hr
Mar 23, 11:40 AM MDTSpecial Weather StatementBOU50 min
Mar 25, 7:31 PM MDTDense Fog AdvisoryBOU13 hr
Apr 2, 1:25 PM MDTRed Flag WarningBOU29 hr
Apr 10, 3:44 AM MDTRed Flag WarningBOU39 hr
Apr 10, 3:44 AM MDTRed Flag WarningBOU65 hr
Apr 11, 2:59 PM MDTHigh Wind WatchBOU19 hr
Apr 12, 9:49 AM MDTHigh Wind WarningBOU53 hr
Apr 15, 1:57 PM MDTFire Weather WatchBOU14 hr
Apr 16, 3:45 AM MDTRed Flag WarningBOU42 hr
Apr 16, 2:16 PM MDTHigh Wind WatchBOU18 hr
Apr 17, 4:58 AM MDTHigh Wind WarningBOU16 hr
Apr 18, 8:27 PM MDTRed Flag WarningBOU24 hr
Apr 29, 2:53 PM MDTRed Flag WarningBOU28 hr
May 1, 1:01 PM MDTMesoscale DiscussionSPC119 min
May 11, 10:58 PM MDTDense Fog AdvisoryBOU10 hr
May 13, 4:10 PM MDTSevere Thunderstorm WarningBOU35 min
May 13, 4:19 PM MDTMesoscale DiscussionSPC2 hr
May 13, 4:40 PM MDTSevere Thunderstorm WarningBOU20 min
May 13, 7:30 PM MDTSevere Thunderstorm WarningBOU30 min
May 14, 12:03 AM MDTSpecial Weather StatementBOU42 min
May 14, 12:38 PM MDTMesoscale DiscussionSPC2 hr
May 14, 12:54 PM MDTAreal Flood AdvisoryBOU38 min
May 17, 4:19 PM MDTMesoscale DiscussionSPC116 min
May 18, 11:02 AM MDTFlash Flood WatchBOU30 hr
May 18, 3:06 PM MDTMesoscale DiscussionSPC114 min
May 21, 3:00 PM MDTMesoscale DiscussionSPC2 hr
May 23, 1:00 PM MDTMesoscale DiscussionSPC2 hr
May 27, 1:13 PM MDTSevere Thunderstorm WatchSPC7 hr
May 27, 1:45 PM MDTTornado WarningBOU30 min
May 27, 4:30 PM MDTMesoscale DiscussionSPC2 hr
May 28, 1:39 PM MDTMesoscale DiscussionSPC96 min
May 28, 2:01 PM MDTSevere Thunderstorm WatchSPC7 hr
May 28, 6:08 PM MDTMesoscale DiscussionSPC97 min
May 30, 1:25 PM MDTMesoscale DiscussionSPC2 hr
Jun 6, 2:49 PM MDTMesoscale DiscussionSPC86 min
Jun 7, 4:08 PM MDTSpecial Weather StatementBOU37 min
Jun 13, 1:42 PM MDTMesoscale DiscussionSPC2 hr
Jun 15, 2:46 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 15, 4:09 PM MDTSpecial Weather StatementBOU36 min
Jun 15, 4:18 PM MDTSevere Thunderstorm WarningBOU27 min
Jun 15, 4:47 PM MDTMesoscale DiscussionSPC88 min
Jun 17, 4:20 PM MDTSevere Thunderstorm WarningBOU25 min
Jun 18, 3:06 PM MDTMesoscale DiscussionSPC114 min
Jun 18, 6:37 PM MDTSevere Thunderstorm WatchSPC6 hr
Jun 18, 7:24 PM MDTSevere Thunderstorm WarningBOU51 min
Jun 18, 8:16 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 18, 8:31 PM MDTMesoscale DiscussionSPC119 min
Jun 18, 8:44 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 19, 11:48 AM MDTMesoscale DiscussionSPC117 min
Jun 19, 12:25 PM MDTTornado WatchSPC7 hr
Jun 19, 1:29 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 19, 1:54 PM MDTMesoscale DiscussionSPC2 hr
Jun 19, 2:13 PM MDTSevere Thunderstorm WarningBOU47 min
Jun 19, 2:20 PM MDTTornado Warning Tornado observedBOU25 min
Jun 19, 2:45 PM MDTTornado WarningBOU30 min
Jun 19, 3:57 PM MDTSevere Thunderstorm WarningBOU23 min
Jun 19, 6:21 PM MDTMesoscale DiscussionSPC54 min
Jun 22, 10:51 AM MDTSevere Thunderstorm WarningBOU39 min
Jun 22, 4:17 PM MDTSpecial Weather StatementBOU58 min
Jun 22, 4:39 PM MDTSpecial Weather StatementBOU36 min
Jun 24, 12:47 PM MDTSpecial Weather StatementBOU43 min
Jun 24, 12:51 PM MDTMesoscale DiscussionSPC84 min
Jun 27, 4:49 PM MDTSevere Thunderstorm WarningBOU26 min
Jun 30, 1:03 PM MDTMesoscale DiscussionSPC87 min
Jun 30, 2:03 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 30, 4:40 PM MDTMesoscale DiscussionSPC2 hr
Jul 4, 1:51 PM MDTMesoscale DiscussionSPC54 min
Jul 4, 4:16 PM MDTSevere Thunderstorm WarningBOU32 min
Jul 4, 5:33 PM MDTSevere Thunderstorm WarningBOU42 min
Jul 4, 6:11 PM MDTSevere Thunderstorm WarningBOU49 min
Jul 5, 2:24 AM MDTSpecial Weather StatementBOU51 min
Jul 5, 5:15 PM MDTAreal Flood AdvisoryBOU31 min
Jul 15, 4:14 AM MDTFlash Flood WatchBOU16 hr
Jul 16, 3:36 AM MDTDense Fog AdvisoryBOU3 hr
Jul 23, 1:00 PM MDTMesoscale DiscussionSPC90 min
Jul 23, 4:16 PM MDTAreal Flood AdvisoryBOU89 min
Jul 23, 5:47 PM MDTAreal Flood AdvisoryBOU55 min
Jul 23, 7:42 PM MDTAreal Flood AdvisoryBOU80 min
Jul 24, 3:44 PM MDTMesoscale DiscussionSPC2 hr
Jul 24, 6:28 PM MDTSevere Thunderstorm WarningBOU46 min
Jul 24, 6:41 PM MDTFlash Flood WarningBOU2 hr
Jul 25, 10:41 AM MDTFlash Flood WatchBOU11 hr
Jul 25, 12:48 PM MDTMesoscale DiscussionSPC57 min
Jul 25, 1:22 PM MDTSevere Thunderstorm WatchSPC6 hr
Jul 25, 5:08 PM MDTMesoscale DiscussionSPC2 hr
Jul 25, 6:33 PM MDTSevere Thunderstorm WarningBOU42 min
Jul 25, 6:38 PM MDTSevere Thunderstorm WarningBOU52 min
Jul 25, 7:08 PM MDTAreal Flood AdvisoryBOU80 min
Jul 25, 7:25 PM MDTSevere Thunderstorm WarningBOU16 min
Jul 25, 7:46 PM MDTAreal Flood AdvisoryBOU45 min
Jul 26, 12:49 PM MDTMesoscale DiscussionSPC56 min
Jul 26, 1:49 PM MDTSevere Thunderstorm WatchSPC7 hr
Jul 26, 6:07 PM MDTMesoscale DiscussionSPC113 min
Jul 26, 9:10 PM MDTSevere Thunderstorm WarningBOU35 min
Jul 27, 12:35 PM MDTMesoscale DiscussionSPC85 min
Jul 27, 1:04 PM MDTTornado WatchSPC8 hr
Jul 27, 3:45 PM MDTSevere Thunderstorm WarningBOU25 min
Jul 27, 4:10 PM MDTTornado WarningBOU35 min
Jul 29, 12:46 PM MDTMesoscale DiscussionSPC59 min
Jul 29, 1:07 PM MDTTornado WatchSPC8 hr
Jul 29, 5:23 PM MDTMesoscale DiscussionSPC67 min
Jul 29, 7:28 PM MDTSevere Thunderstorm WarningBOU32 min
Jul 29, 7:59 PM MDTSevere Thunderstorm WarningBOU31 min
Jul 29, 8:27 PM MDTSevere Thunderstorm WarningBOU33 min
Aug 3, 8:39 PM MDTSevere Thunderstorm WarningBOU51 min
Aug 4, 10:42 PM MDTSpecial Weather StatementBOU48 min
Aug 6, 2:37 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 6, 5:24 PM MDTMesoscale DiscussionSPC66 min
Aug 6, 5:56 PM MDTSevere Thunderstorm WarningBOU22 min
Aug 6, 6:48 PM MDTSevere Thunderstorm WarningBOU42 min
Aug 6, 7:14 PM MDTSevere Thunderstorm WarningBOU31 min
Aug 6, 8:06 PM MDTMesoscale DiscussionSPC54 min
Aug 6, 8:25 PM MDTSevere Thunderstorm WarningBOU35 min
Aug 6, 9:00 PM MDTSevere Thunderstorm WarningBOU11 min
Aug 7, 12:59 PM MDTMesoscale DiscussionSPC2 hr
Aug 7, 6:14 PM MDTSevere Thunderstorm WarningBOU27 min
Aug 7, 7:24 PM MDTSevere Thunderstorm WarningBOU19 min
Aug 7, 7:57 PM MDTMesoscale DiscussionSPC2 hr
Aug 14, 5:31 PM MDTMesoscale DiscussionSPC119 min
Aug 14, 5:47 PM MDTSevere Thunderstorm WarningBOU28 min
Aug 14, 5:51 PM MDTAreal Flood AdvisoryBOU114 min
Aug 14, 6:13 PM MDTSevere Thunderstorm WarningBOU47 min
Aug 14, 7:09 PM MDTAreal Flood AdvisoryBOU96 min
Aug 14, 7:29 PM MDTSevere Thunderstorm WarningBOU46 min
Aug 17, 2:56 PM MDTMesoscale DiscussionSPC2 hr
Aug 17, 3:30 PM MDTSpecial Weather StatementBOU30 min
Aug 17, 4:06 PM MDTAreal Flood AdvisoryBOU84 min
Aug 18, 10:10 PM MDTSevere Thunderstorm WarningBOU15 min
Aug 26, 3:58 AM MDTFire Weather WatchBOU12 hr
Aug 26, 3:35 PM MDTRed Flag WarningBOU26 hr
Sep 5, 2:31 AM MDTAreal Flood AdvisoryBOU89 min
Sep 5, 3:57 AM MDTAreal Flood AdvisoryBOU93 min
Sep 5, 3:14 PM MDTAreal Flood AdvisoryBOU61 min
Sep 7, 4:04 AM MDTDense Fog AdvisoryBOU5 hr
Sep 9, 5:26 PM MDTSpecial Weather StatementBOU49 min
Sep 24, 2:24 PM MDTMesoscale DiscussionSPC3 hr
Oct 7, 2:30 PM MDTFreeze WatchBOU25 hr
Oct 8, 3:01 PM MDTFreeze WarningBOU13 hr
Oct 9, 4:25 AM MDTFreeze WarningBOU30 hr
Oct 10, 2:27 PM MDTFreeze WarningBOU19 hr
Oct 12, 2:20 PM MDTWinter Weather AdvisoryBOU49 hr
Nov 2, 10:35 PM MDTSevere Thunderstorm WarningBOU33 min
Nov 10, 4:18 AM MSTWinter Weather AdvisoryBOU44 hr
Nov 16, 10:36 AM MSTWinter Weather AdvisoryBOU34 hr
Nov 24, 5:39 AM MSTHigh Wind WarningBOU19 hr
Dec 17, 3:32 PM MSTHigh Wind WatchBOU18 hr
Dec 18, 9:57 AM MSTHigh Wind WarningBOU31 hr
Dec 30, 1:56 PM MSTWinter Weather AdvisoryBOU27 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 archive20172019

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.