Alert archive / Colorado / Adams County

Weather alerts in Adams County, Colorado, 2019

203 weather alerts in 2019, 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 2019. Tap one for its archive.

Alerts
203
Warnings
58
Watches
31
Advisories
42
Busiest month
June40 alerts
Busiest day
June 8, 201911 alerts

Over time

By month

Warning verification

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

3 of 4 tornado warnings covering Adams County in 2019 had a tornado report inside them; 4 of 5 tornado reports fell inside a warning, on average 7 minutes after it went out.

Adams County, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings4325%580%7 min
Severe thunderstorm warnings372046%1182%17 min
Flash flood warnings30100%0

Each office's whole area, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Denver/Boulder, CO: tornado warnings321166%3348%11 min
NWS Denver/Boulder, CO: severe thunderstorm warnings28111758%38277%18 min
NWS Denver/Boulder, CO: flash flood warnings15287%367%58 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 6, 8:09 PM MSTHigh Wind WatchBOU7 hr
Jan 10, 2:42 PM MSTWinter Weather AdvisoryBOU33 hr
Jan 20, 3:01 PM MSTWinter Storm WatchBOU20 hr
Jan 20, 3:01 PM MSTWinter Weather AdvisoryBOU42 hr
Jan 21, 11:18 AM MSTBlizzard WarningBOU24 hr
Jan 27, 9:05 PM MSTSpecial Weather StatementBOU40 min
Feb 5, 4:11 AM MSTWinter Weather AdvisoryBOU48 hr
Feb 20, 3:59 PM MSTWinter Weather AdvisoryBOU66 hr
Feb 25, 11:00 PM MSTDense Fog AdvisoryBOU9 hr
Feb 27, 3:10 AM MSTDense Fog AdvisoryBOU6 hr
Feb 28, 5:33 PM MSTWinter Storm WatchBOU17 hr
Feb 28, 5:33 PM MSTWinter Weather AdvisoryBOU58 hr
Mar 2, 6:44 PM MSTMesoscale DiscussionSPC4 hr
Mar 3, 3:36 AM MSTWind Chill AdvisoryBOU5 hr
Mar 3, 3:36 AM MSTWind Chill AdvisoryBOU29 hr
Mar 11, 6:48 AM MDTWinter Storm WatchBOU28 hr
Mar 11, 3:24 PM MDTBlizzard WarningBOU68 hr
Mar 13, 10:27 AM MDTMesoscale DiscussionSPC3 hr
Mar 13, 1:37 PM MDTMesoscale DiscussionSPC4 hr
Mar 13, 5:26 PM MDTMesoscale DiscussionSPC6 hr
Mar 14, 11:52 AM MDTWinter Weather AdvisoryBOU6 hr
Apr 3, 7:18 PM MDTSpecial Weather StatementBOU27 min
Apr 7, 3:05 PM MDTFire Weather WatchBOU21 hr
Apr 8, 12:03 PM MDTRed Flag WarningBOU31 hr
Apr 8, 3:10 PM MDTWinter Storm WatchBOU21 hr
Apr 9, 11:47 AM MDTBlizzard WarningBOU47 hr
Apr 10, 8:31 PM MDTWinter Weather AdvisoryBOU22 hr
May 6, 12:50 PM MDTMesoscale DiscussionSPC115 min
May 6, 6:45 PM MDTSevere Thunderstorm WarningBOU45 min
May 6, 6:47 PM MDTSevere Thunderstorm WarningBOU22 min
May 7, 1:01 AM MDTDense Fog AdvisoryBOU7 hr
May 7, 8:53 PM MDTDense Fog AdvisoryBOU12 hr
May 8, 3:50 PM MDTFreeze WatchBOU24 hr
May 9, 4:03 PM MDTFrost AdvisoryBOU16 hr
May 10, 2:51 PM MDTFrost AdvisoryBOU18 hr
May 11, 5:45 PM MDTFrost AdvisoryBOU14 hr
May 16, 4:36 PM MDTSpecial Weather StatementBOU39 min
May 18, 2:49 PM MDTFrost AdvisoryBOU17 hr
May 20, 4:50 AM MDTWinter Weather AdvisoryBOU31 hr
May 21, 12:01 PM MDTFreeze WarningBOU19 hr
May 26, 2:07 PM MDTMesoscale DiscussionSPC113 min
May 26, 3:46 PM MDTTornado WatchSPC4 hr
May 26, 3:51 PM MDTSevere Thunderstorm WarningBOU39 min
May 26, 4:34 PM MDTTornado WarningBOU26 min
May 26, 5:23 PM MDTSevere Thunderstorm WarningBOU32 min
May 26, 5:30 PM MDTTornado WarningBOU15 min
May 27, 12:36 PM MDTMesoscale DiscussionSPC2 hr
May 27, 12:50 PM MDTSevere Thunderstorm WarningBOU40 min
May 27, 12:56 PM MDTTornado WatchSPC8 hr
May 27, 1:28 PM MDTSevere Thunderstorm WarningBOU47 min
May 27, 1:42 PM MDTTornado WarningBOU33 min
May 27, 2:43 PM MDTMesoscale DiscussionSPC2 hr
May 27, 4:49 PM MDTTornado WarningBOU26 min
May 28, 1:44 AM MDTSevere Thunderstorm WarningBOU31 min
Jun 2, 10:57 AM MDTMesoscale DiscussionSPC2 hr
Jun 2, 12:11 PM MDTSevere Thunderstorm WatchSPC8 hr
Jun 2, 2:26 PM MDTMesoscale DiscussionSPC2 hr
Jun 2, 3:14 PM MDTSpecial Weather StatementBOU46 min
Jun 3, 1:31 PM MDTMesoscale DiscussionSPC119 min
Jun 3, 1:53 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 3, 2:22 PM MDTSpecial Weather StatementBOU23 min
Jun 4, 12:59 PM MDTMesoscale DiscussionSPC2 hr
Jun 7, 12:37 PM MDTMesoscale DiscussionSPC2 hr
Jun 7, 2:43 PM MDTSpecial Weather StatementBOU47 min
Jun 7, 6:31 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 7, 7:03 PM MDTSevere Thunderstorm WarningBOU42 min
Jun 8, 1:18 PM MDTMesoscale DiscussionSPC87 min
Jun 8, 3:39 PM MDTSevere Thunderstorm WarningBOU40 min
Jun 8, 3:44 PM MDTMesoscale DiscussionSPC61 min
Jun 8, 3:44 PM MDTSevere Thunderstorm WatchSPC5 hr
Jun 8, 4:35 PM MDTSevere Thunderstorm WarningBOU25 min
Jun 8, 4:58 PM MDTSevere Thunderstorm WarningBOU32 min
Jun 8, 5:25 PM MDTSevere Thunderstorm WarningBOU37 min
Jun 8, 5:45 PM MDTSevere Thunderstorm WarningBOU45 min
Jun 8, 5:58 PM MDTSevere Thunderstorm WarningBOU32 min
Jun 8, 6:19 PM MDTMesoscale DiscussionSPC86 min
Jun 8, 6:33 PM MDTSevere Thunderstorm WarningBOU27 min
Jun 8, 8:09 PM MDTMesoscale DiscussionSPC96 min
Jun 13, 5:58 PM MDTMesoscale DiscussionSPC92 min
Jun 14, 12:44 PM MDTMesoscale DiscussionSPC3 hr
Jun 16, 4:18 PM MDTSpecial Weather StatementBOU27 min
Jun 17, 12:04 PM MDTMesoscale DiscussionSPC86 min
Jun 17, 4:30 PM MDTMesoscale DiscussionSPC90 min
Jun 17, 5:59 PM MDTAreal Flood AdvisoryBOU2 hr
Jun 20, 2:47 PM MDTSevere Thunderstorm WarningBOU43 min
Jun 20, 2:51 PM MDTMesoscale DiscussionSPC114 min
Jun 20, 3:30 PM MDTSpecial Weather StatementBOU30 min
Jun 20, 3:59 PM MDTSpecial Weather StatementBOU31 min
Jun 20, 4:56 PM MDTSevere Thunderstorm WarningBOU49 min
Jun 21, 11:56 AM MDTMesoscale DiscussionSPC94 min
Jun 22, 2:11 PM MDTMesoscale DiscussionSPC2 hr
Jun 22, 4:08 PM MDTMesoscale DiscussionSPC67 min
Jun 23, 12:41 PM MDTMesoscale DiscussionSPC2 hr
Jun 28, 9:55 PM MDTSpecial Weather StatementBOU50 min
Jul 1, 11:02 PM MDTAreal Flood AdvisoryBOU118 min
Jul 1, 11:07 PM MDTAreal Flood AdvisoryBOU113 min
Jul 4, 2:10 PM MDTMesoscale DiscussionSPC2 hr
Jul 4, 3:01 PM MDTTornado WatchSPC7 hr
Jul 4, 5:31 PM MDTSevere Thunderstorm WarningBOU22 min
Jul 4, 5:40 PM MDTMesoscale DiscussionSPC95 min
Jul 4, 6:12 PM MDTSevere Thunderstorm WarningBOU48 min
Jul 4, 6:56 PM MDTSevere Thunderstorm WarningBOU17 min
Jul 4, 7:50 PM MDTSevere Thunderstorm WarningBOU25 min
Jul 5, 1:18 PM MDTMesoscale DiscussionSPC117 min
Jul 5, 3:36 PM MDTSevere Thunderstorm WatchSPC8 hr
Jul 5, 6:01 PM MDTMesoscale DiscussionSPC89 min
Jul 5, 6:10 PM MDTSevere Thunderstorm WarningBOU50 min
Jul 5, 6:27 PM MDTAreal Flood AdvisoryBOU112 min
Jul 5, 6:53 PM MDTSevere Thunderstorm WarningBOU37 min
Jul 5, 7:01 PM MDTSevere Thunderstorm WarningBOU44 min
Jul 5, 7:20 PM MDTSevere Thunderstorm WarningBOU25 min
Jul 5, 7:38 PM MDTAreal Flood AdvisoryBOU2 hr
Jul 5, 9:18 PM MDTMesoscale DiscussionSPC57 min
Jul 6, 12:25 PM MDTMesoscale DiscussionSPC95 min
Jul 6, 12:42 PM MDTSevere Thunderstorm WatchSPC10 hr
Jul 6, 4:55 PM MDTMesoscale DiscussionSPC95 min
Jul 6, 8:06 PM MDTMesoscale DiscussionSPC84 min
Jul 7, 2:14 PM MDTMesoscale DiscussionSPC3 hr
Jul 13, 5:04 PM MDTSpecial Weather StatementBOU41 min
Jul 20, 12:53 PM MDTMesoscale DiscussionSPC3 hr
Jul 20, 2:29 PM MDTSevere Thunderstorm WatchSPC7 hr
Jul 20, 3:22 PM MDTAreal Flood AdvisoryBOU83 min
Jul 20, 5:43 PM MDTMesoscale DiscussionSPC92 min
Jul 20, 6:09 PM MDTFlash Flood WarningBOU2 hr
Jul 21, 4:37 PM MDTMesoscale DiscussionSPC83 min
Jul 21, 10:34 PM MDTAreal Flood AdvisoryBOU116 min
Jul 22, 5:38 PM MDTMesoscale DiscussionSPC67 min
Jul 22, 5:52 PM MDTSevere Thunderstorm WarningBOU23 min
Jul 24, 6:29 PM MDTSpecial Weather StatementBOU31 min
Jul 29, 1:52 PM MDTMesoscale DiscussionSPC113 min
Jul 30, 5:31 PM MDTSevere Thunderstorm WarningBOU29 min
Jul 31, 8:29 PM MDTAreal Flood AdvisoryBOU2 hr
Aug 1, 3:14 AM MDTFlash Flood WatchBOU20 hr
Aug 1, 1:25 PM MDTMesoscale DiscussionSPC95 min
Aug 1, 1:55 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 1, 3:07 PM MDTSpecial Weather StatementBOU38 min
Aug 5, 4:16 PM MDTSpecial Weather StatementBOU44 min
Aug 7, 7:05 PM MDTAreal Flood AdvisoryBOU85 min
Aug 11, 12:54 PM MDTMesoscale DiscussionSPC2 hr
Aug 11, 1:24 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 11, 3:24 PM MDTSevere Thunderstorm WarningBOU36 min
Aug 11, 3:28 PM MDTSevere Thunderstorm WarningBOU32 min
Aug 11, 3:54 PM MDTSevere Thunderstorm WarningBOU36 min
Aug 11, 4:51 PM MDTMesoscale DiscussionSPC114 min
Aug 13, 11:09 PM MDTSevere Thunderstorm WarningBOU20 min
Aug 14, 1:54 PM MDTMesoscale DiscussionSPC2 hr
Aug 14, 3:00 PM MDTSevere Thunderstorm WatchSPC6 hr
Aug 14, 5:58 PM MDTMesoscale DiscussionSPC92 min
Aug 16, 1:40 PM MDTMesoscale DiscussionSPC65 min
Aug 16, 2:54 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 16, 5:27 PM MDTMesoscale DiscussionSPC2 hr
Aug 16, 7:43 PM MDTMesoscale DiscussionSPC2 hr
Aug 17, 1:34 PM MDTMesoscale DiscussionSPC116 min
Aug 20, 5:54 PM MDTSevere Thunderstorm WarningBOU51 min
Aug 20, 6:30 PM MDTSevere Thunderstorm WarningBOU45 min
Aug 20, 7:10 PM MDTFlash Flood WarningBOU2 hr
Aug 21, 2:47 PM MDTSevere Thunderstorm WatchSPC6 hr
Aug 21, 6:22 PM MDTAreal Flood AdvisoryBOU113 min
Aug 21, 6:40 PM MDTFlash Flood WarningBOU2 hr
Aug 22, 2:11 PM MDTMesoscale DiscussionSPC94 min
Aug 22, 3:23 PM MDTSpecial Weather StatementBOU22 min
Aug 23, 1:55 PM MDTMesoscale DiscussionSPC110 min
Aug 23, 2:34 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 23, 3:23 PM MDTSevere Thunderstorm WarningBOU26 min
Aug 23, 4:28 PM MDTMesoscale DiscussionSPC2 hr
Aug 30, 2:13 PM MDTMesoscale DiscussionSPC3 hr
Sep 6, 4:43 PM MDTAreal Flood AdvisoryBOU68 min
Sep 8, 2:40 PM MDTMesoscale DiscussionSPC95 min
Sep 8, 2:56 PM MDTSevere Thunderstorm WatchSPC6 hr
Sep 8, 5:53 PM MDTSpecial Weather StatementBOU37 min
Sep 8, 6:05 PM MDTSevere Thunderstorm WarningBOU40 min
Sep 8, 6:34 PM MDTSevere Thunderstorm WarningBOU41 min
Sep 20, 10:02 AM MDTRed Flag WarningBOU10 hr
Sep 27, 3:02 PM MDTFire Weather WatchBOU13 hr
Sep 27, 3:02 PM MDTFire Weather WatchBOU37 hr
Sep 28, 4:15 AM MDTRed Flag WarningBOU39 hr
Sep 29, 3:56 AM MDTRed Flag WarningBOU39 hr
Oct 2, 2:26 AM MDTFrost AdvisoryBOU30 hr
Oct 6, 3:37 AM MDTFrost AdvisoryBOU28 hr
Oct 8, 3:06 PM MDTFreeze WatchBOU13 hr
Oct 9, 4:18 AM MDTFreeze WarningBOU29 hr
Oct 9, 3:17 PM MDTWinter Weather AdvisoryBOU23 hr
Oct 18, 2:31 PM MDTFire Weather WatchBOU23 hr
Oct 23, 3:54 AM MDTWinter Weather AdvisoryBOU27 hr
Oct 25, 1:52 PM MDTWinter Storm WatchBOU24 hr
Oct 26, 1:54 PM MDTWinter Weather AdvisoryBOU46 hr
Oct 28, 5:17 AM MDTMesoscale DiscussionSPC3 hr
Oct 28, 2:26 PM MDTWinter Storm WarningBOU37 hr
Nov 6, 2:54 PM MSTWinter Weather AdvisoryBOU12 hr
Nov 10, 2:55 PM MSTWinter Weather AdvisoryBOU18 hr
Nov 21, 4:11 AM MSTWinter Weather AdvisoryBOU5 hr
Nov 24, 4:38 AM MSTWinter Storm WatchBOU9 hr
Nov 24, 1:40 PM MSTWinter Storm WarningBOU51 hr
Nov 24, 1:40 PM MSTWinter Weather AdvisoryBOU51 hr
Nov 25, 7:42 PM MSTMesoscale DiscussionSPC6 hr
Nov 26, 4:16 AM MSTBlizzard WarningBOU8 hr
Nov 29, 1:44 AM MSTDense Fog AdvisoryBOU9 hr
Nov 29, 3:02 AM MSTHigh Wind WarningBOU39 hr
Nov 29, 5:39 PM MSTDense Fog AdvisoryBOU6 hr
Dec 26, 3:36 AM MSTWinter Storm WatchBOU34 hr
Dec 26, 7:16 AM MSTDense Fog AdvisoryBOU3 hr
Dec 27, 1:57 PM MSTWinter Storm WarningBOU34 hr
Dec 27, 1:57 PM MSTWinter Weather AdvisoryBOU34 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 archive20182020

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.