Alert archive / Colorado / Washington County

Weather alerts in Washington County, Colorado, 2023

256 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Washington County and its neighbors

Each county as a circle sized by its count in 2023. Tap one for its archive.

Alerts
256
Warnings
100
Watches
37
Advisories
38
Busiest month
June78 alerts
Busiest day
June 21, 202325 alerts

Over time

By month

Warning verification

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

10 of 21 tornado warnings covering Washington County in 2023 had a tornado report inside them; 43 of 49 tornado reports fell inside a warning, on average 15 minutes after it went out.

Washington County, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings211052%4988%15 min
Severe thunderstorm warnings591575%3450%17 min
Flash flood warnings4175%1100%150 min

Each office's whole area, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Denver/Boulder, CO: tornado warnings672070%7971%13 min
NWS Denver/Boulder, CO: severe thunderstorm warnings46716964%52175%18 min
NWS Denver/Boulder, CO: flash flood warnings801976%3574%74 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, 3:06 AM MSTWinter Weather AdvisoryBOU45 hr
Jan 2, 6:09 PM MSTWinter Storm WarningBOU14 hr
Jan 10, 2:06 PM MSTWinter Weather AdvisoryBOU33 hr
Jan 11, 11:52 AM MSTMesoscale DiscussionSPC3 hr
Jan 15, 2:52 PM MSTWinter Storm WatchBOU22 hr
Jan 16, 12:36 PM MSTWinter Storm WarningBOU58 hr
Jan 29, 3:28 AM MSTWind Chill AdvisoryBOU30 hr
Jan 30, 3:16 AM MSTWind Chill AdvisoryBOU29 hr
Feb 14, 2:59 AM MSTWinter Storm WarningBOU45 hr
Feb 14, 2:59 AM MSTWinter Weather AdvisoryBOU45 hr
Feb 21, 2:53 PM MSTWind Chill AdvisoryBOU42 hr
Feb 22, 2:45 PM MSTWind Chill WarningBOU18 hr
Feb 23, 2:00 PM MSTWind Chill AdvisoryBOU19 hr
Mar 7, 6:21 AM MSTWinter Weather AdvisoryBOU5 hr
Mar 25, 2:39 AM MDTWinter Weather AdvisoryBOU24 hr
Mar 26, 2:20 PM MDTWinter Weather AdvisoryBOU28 hr
Mar 27, 9:08 AM MDTWinter Storm WarningBOU9 hr
Apr 11, 2:33 PM MDTFire Weather WatchBOU24 hr
Apr 12, 2:35 PM MDTRed Flag WarningBOU29 hr
Apr 16, 5:02 AM MDTFire Weather WatchBOU34 hr
Apr 17, 2:35 PM MDTRed Flag WarningBOU29 hr
Apr 19, 4:49 PM MDTSpecial Weather StatementBOU41 min
Apr 19, 5:22 PM MDTBlowing Dust AdvisoryBOU4 hr
May 4, 2:13 PM MDTSpecial Weather StatementBOU47 min
May 8, 7:19 PM MDTSpecial Weather StatementBOU26 min
May 10, 3:08 AM MDTFlood WatchBOU57 hr
May 10, 1:25 PM MDTMesoscale DiscussionSPC2 hr
May 10, 1:55 PM MDTTornado WatchSPC7 hr
May 10, 4:45 PM MDTMesoscale DiscussionSPC90 min
May 10, 5:49 PM MDTTornado WarningBOU26 min
May 10, 6:05 PM MDTSevere Thunderstorm WarningBOU40 min
May 10, 6:11 PM MDTTornado WarningBOU34 min
May 10, 6:12 PM MDTAreal Flood AdvisoryBOU3 hr
May 10, 6:39 PM MDTTornado WarningBOU36 min
May 16, 12:57 PM MDTMesoscale DiscussionSPC2 hr
May 16, 3:18 PM MDTSpecial Weather StatementBOU27 min
May 16, 5:41 PM MDTSpecial Weather StatementBOU19 min
May 16, 5:43 PM MDTSpecial Weather StatementBOU17 min
May 18, 12:30 PM MDTMesoscale DiscussionSPC2 hr
May 18, 2:25 PM MDTSpecial Weather StatementBOU35 min
May 18, 3:04 PM MDTSpecial Weather StatementBOU26 min
May 18, 4:18 PM MDTMesoscale DiscussionSPC87 min
May 18, 4:35 PM MDTAreal Flood AdvisoryBOU3 hr
May 26, 11:56 AM MDTMesoscale DiscussionSPC2 hr
May 26, 1:33 PM MDTSevere Thunderstorm WatchSPC7 hr
May 26, 4:33 PM MDTMesoscale DiscussionSPC117 min
May 26, 5:43 PM MDTSevere Thunderstorm WarningBOU47 min
May 26, 6:28 PM MDTAreal Flood AdvisoryBOU92 min
May 26, 6:56 PM MDTSpecial Weather StatementBOU64 min
May 26, 7:06 PM MDTTornado Warning Tornado observedBOU24 min
May 27, 10:43 PM MDTAreal Flood AdvisoryBOU3 hr
May 27, 11:21 PM MDTAreal Flood AdvisoryBOU3 hr
May 28, 5:58 PM MDTSevere Thunderstorm WarningBOU47 min
May 28, 6:07 PM MDTSevere Thunderstorm WarningBOU38 min
May 30, 3:34 PM MDTMesoscale DiscussionSPC86 min
May 30, 3:56 PM MDTSevere Thunderstorm WatchSPC7 hr
May 30, 7:10 PM MDTMesoscale DiscussionSPC2 hr
Jun 2, 1:19 PM MDTSpecial Weather StatementBOU26 min
Jun 2, 4:08 PM MDTSpecial Weather StatementBOU37 min
Jun 2, 5:46 PM MDTSpecial Weather StatementBOU29 min
Jun 2, 6:29 PM MDTAreal Flood AdvisoryBOU91 min
Jun 8, 5:00 PM MDTSpecial Weather StatementBOU45 min
Jun 8, 5:45 PM MDTSpecial Weather StatementBOU45 min
Jun 9, 4:46 PM MDTSpecial Weather StatementBOU59 min
Jun 10, 3:45 PM MDTMesoscale DiscussionSPC60 min
Jun 12, 3:24 AM MDTFlood WatchBOU21 hr
Jun 12, 3:09 PM MDTAreal Flood AdvisoryBOU2 hr
Jun 13, 8:19 PM MDTRiver Flood AdvisoryBOU3 days
Jun 13, 10:17 PM MDTRiver Flood WarningBOU17 hr
Jun 14, 3:44 PM MDTRiver Flood AdvisoryBOU10 days
Jun 15, 4:44 PM MDTSpecial Weather StatementBOU46 min
Jun 15, 5:55 PM MDTSpecial Weather StatementBOU50 min
Jun 21, 9:32 AM MDTFlood WatchBOU20 hr
Jun 21, 11:51 AM MDTMesoscale DiscussionSPC2 hr
Jun 21, 12:33 PM MDTTornado WatchSPC7 hr
Jun 21, 1:59 PM MDTSevere Thunderstorm WarningBOU46 min
Jun 21, 2:36 PM MDTSevere Thunderstorm WarningBOU19 min
Jun 21, 2:39 PM MDTSevere Thunderstorm WarningBOU36 min
Jun 21, 2:45 PM MDTMesoscale DiscussionSPC90 min
Jun 21, 3:11 PM MDTSevere Thunderstorm WarningBOU34 min
Jun 21, 3:38 PM MDTAreal Flood AdvisoryBOU3 hr
Jun 21, 3:42 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU33 min
Jun 21, 3:51 PM MDTTornado Warning Tornado observedBOU24 min
Jun 21, 4:02 PM MDTAreal Flood AdvisoryBOU3 hr
Jun 21, 4:05 PM MDTTornado WarningBOU25 min
Jun 21, 4:21 PM MDTTornado WarningBOU24 min
Jun 21, 4:22 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU23 min
Jun 21, 4:37 PM MDTTornado Warning Tornado observedConsiderable damage threatBOU23 min
Jun 21, 4:42 PM MDTFlash Flood WarningBOU3 hr
Jun 21, 4:46 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 21, 4:54 PM MDTTornado Warning Tornado observedConsiderable damage threatBOU21 min
Jun 21, 5:07 PM MDTMesoscale DiscussionSPC83 min
Jun 21, 5:10 PM MDTTornado Warning Tornado observedConsiderable damage threatBOU35 min
Jun 21, 5:27 PM MDTTornado WarningBOU33 min
Jun 21, 5:28 PM MDTSevere Thunderstorm WarningBOU32 min
Jun 21, 5:45 PM MDTSevere Thunderstorm WarningBOU30 min
Jun 21, 5:52 PM MDTTornado Warning Tornado observedConsiderable damage threatBOU23 min
Jun 21, 6:01 PM MDTSevere Thunderstorm WarningBOU29 min
Jun 21, 6:11 PM MDTSevere Thunderstorm WarningBOU34 min
Jun 21, 6:24 PM MDTSevere Thunderstorm WarningBOU51 min
Jun 21, 6:26 PM MDTTornado WarningBOU34 min
Jun 21, 6:53 PM MDTTornado Warning Considerable damage threatBOU37 min
Jun 21, 7:26 PM MDTSevere Thunderstorm WarningBOU34 min
Jun 21, 7:27 PM MDTFlash Flood WarningBOU3 hr
Jun 21, 7:39 PM MDTTornado WarningBOU15 min
Jun 21, 7:56 PM MDTSevere Thunderstorm WarningBOU17 min
Jun 21, 8:38 PM MDTFlash Flood WarningBOU3 hr
Jun 21, 10:24 PM MDTAreal Flood WarningBOU9 hr
Jun 22, 7:24 AM MDTAreal Flood AdvisoryBOU6 hr
Jun 22, 10:13 AM MDTFlood WatchBOU14 hr
Jun 22, 11:08 AM MDTMesoscale DiscussionSPC2 hr
Jun 22, 12:14 PM MDTSevere Thunderstorm WatchSPC10 hr
Jun 22, 7:51 PM MDTRiver Flood WatchBOU37 hr
Jun 23, 9:23 PM MDTTornado WarningBOU37 min
Jun 24, 8:45 AM MDTRiver Flood WarningBOU24 hr
Jun 25, 8:35 AM MDTRiver Flood AdvisoryBOU27 hr
Jun 27, 2:34 PM MDTSevere Thunderstorm WatchSPC8 hr
Jun 28, 8:39 PM MDTMesoscale DiscussionSPC66 min
Jun 28, 9:03 PM MDTSevere Thunderstorm WatchSPC6 hr
Jun 28, 11:01 PM MDTMesoscale DiscussionSPC89 min
Jun 28, 11:08 PM MDTTornado WarningBOU37 min
Jun 28, 11:42 PM MDTTornado WarningBOU33 min
Jun 29, 12:09 AM MDTSevere Thunderstorm Warning Considerable damage threatBOU37 min
Jun 29, 12:26 AM MDTTornado WarningBOU34 min
Jun 29, 12:54 AM MDTMesoscale DiscussionSPC96 min
Jun 29, 1:00 AM MDTSevere Thunderstorm Warning Considerable damage threatBOU30 min
Jun 29, 1:27 AM MDTSevere Thunderstorm WarningBOU33 min
Jun 29, 1:17 PM MDTTornado WatchSPC8 hr
Jun 29, 4:12 PM MDTMesoscale DiscussionSPC93 min
Jun 29, 6:52 PM MDTMesoscale DiscussionSPC83 min
Jun 29, 6:58 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU47 min
Jun 29, 7:38 PM MDTSevere Thunderstorm WarningBOU37 min
Jun 30, 1:08 AM MDTSpecial Weather StatementBOU52 min
Jun 30, 12:10 PM MDTMesoscale DiscussionSPC2 hr
Jun 30, 12:56 PM MDTSevere Thunderstorm WatchSPC6 hr
Jul 4, 1:41 PM MDTMesoscale DiscussionSPC64 min
Jul 4, 2:05 PM MDTSevere Thunderstorm WatchSPC9 hr
Jul 4, 5:14 PM MDTMesoscale DiscussionSPC91 min
Jul 4, 8:34 PM MDTMesoscale DiscussionSPC116 min
Jul 6, 7:26 AM MDTSpecial Weather StatementBOU49 min
Jul 6, 2:51 PM MDTSevere Thunderstorm WatchSPC7 hr
Jul 8, 12:23 PM MDTMesoscale DiscussionSPC97 min
Jul 8, 1:09 PM MDTSevere Thunderstorm WatchSPC8 hr
Jul 8, 4:18 PM MDTMesoscale DiscussionSPC117 min
Jul 8, 4:22 PM MDTTornado WarningBOU23 min
Jul 8, 4:38 PM MDTSevere Thunderstorm WarningBOU52 min
Jul 10, 12:47 PM MDTMesoscale DiscussionSPC118 min
Jul 10, 1:37 PM MDTSevere Thunderstorm WatchSPC7 hr
Jul 13, 12:09 PM MDTSevere Thunderstorm WarningBOU36 min
Jul 13, 12:09 PM MDTMesoscale DiscussionSPC2 hr
Jul 13, 12:29 PM MDTSevere Thunderstorm WatchSPC10 hr
Jul 13, 12:43 PM MDTSevere Thunderstorm WarningBOU22 min
Jul 13, 1:00 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 14, 1:42 PM MDTMesoscale DiscussionSPC3 hr
Jul 20, 3:02 AM MDTFlood WatchBOU21 hr
Jul 20, 7:38 AM MDTSpecial Weather StatementBOU52 min
Jul 20, 8:09 AM MDTSevere Thunderstorm Warning Considerable damage threatBOU51 min
Jul 20, 12:15 PM MDTMesoscale DiscussionSPC2 hr
Jul 20, 1:27 PM MDTSevere Thunderstorm WatchSPC9 hr
Jul 20, 2:56 PM MDTSevere Thunderstorm WarningBOU49 min
Jul 20, 4:16 PM MDTSevere Thunderstorm WarningBOU32 min
Jul 20, 4:19 PM MDTMesoscale DiscussionSPC116 min
Jul 20, 4:59 PM MDTSpecial Weather StatementBOU46 min
Jul 20, 5:05 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 20, 5:10 PM MDTSevere Thunderstorm WarningBOU50 min
Jul 20, 5:28 PM MDTSevere Thunderstorm WarningBOU47 min
Jul 20, 5:43 PM MDTSevere Thunderstorm WarningBOU47 min
Jul 20, 6:07 PM MDTAreal Flood AdvisoryBOU3 hr
Jul 21, 7:11 PM MDTSevere Thunderstorm WarningBOU34 min
Jul 25, 4:34 PM MDTMesoscale DiscussionSPC86 min
Jul 25, 6:10 PM MDTSevere Thunderstorm WarningBOU50 min
Jul 26, 2:37 PM MDTMesoscale DiscussionSPC113 min
Jul 29, 2:48 PM MDTMesoscale DiscussionSPC117 min
Jul 31, 2:37 PM MDTFlood WatchBOU32 hr
Jul 31, 10:49 PM MDTSpecial Weather StatementBOU41 min
Jul 31, 10:51 PM MDTSevere Thunderstorm WarningBOU24 min
Aug 1, 2:33 PM MDTMesoscale DiscussionSPC87 min
Aug 1, 3:58 PM MDTSpecial Weather StatementBOU32 min
Aug 1, 4:06 PM MDTSevere Thunderstorm WarningBOU24 min
Aug 1, 4:28 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU47 min
Aug 1, 5:37 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 1, 6:49 PM MDTMesoscale DiscussionSPC86 min
Aug 1, 8:25 PM MDTSpecial Weather StatementBOU50 min
Aug 2, 11:57 PM MDTSpecial Weather StatementBOU48 min
Aug 3, 2:13 PM MDTMesoscale DiscussionSPC2 hr
Aug 3, 2:57 PM MDTSevere Thunderstorm WatchSPC8 hr
Aug 3, 6:22 PM MDTSpecial Weather StatementBOU53 min
Aug 3, 6:42 PM MDTMesoscale DiscussionSPC2 hr
Aug 4, 11:23 PM MDTSpecial Weather StatementBOU52 min
Aug 4, 11:52 PM MDTSevere Thunderstorm WarningBOU23 min
Aug 5, 12:16 AM MDTSevere Thunderstorm WarningBOU29 min
Aug 5, 1:24 AM MDTSpecial Weather StatementBOU36 min
Aug 5, 1:43 AM MDTAreal Flood AdvisoryBOU2 hr
Aug 5, 1:55 AM MDTSevere Thunderstorm WarningBOU35 min
Aug 5, 2:02 AM MDTSevere Thunderstorm WarningBOU28 min
Aug 5, 2:18 AM MDTSevere Thunderstorm WarningBOU27 min
Aug 5, 2:23 AM MDTFlash Flood WarningBOU3 hr
Aug 5, 2:40 AM MDTSevere Thunderstorm WarningBOU16 min
Aug 5, 2:49 AM MDTSevere Thunderstorm WarningBOU26 min
Aug 5, 12:44 PM MDTMesoscale DiscussionSPC3 hr
Aug 5, 1:32 PM MDTSevere Thunderstorm WatchSPC10 hr
Aug 5, 2:57 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU48 min
Aug 5, 3:42 PM MDTSevere Thunderstorm Warning Considerable damage threatBOU47 min
Aug 5, 4:49 PM MDTSevere Thunderstorm WarningBOU41 min
Aug 5, 4:57 PM MDTSevere Thunderstorm WarningBOU35 min
Aug 5, 5:09 PM MDTMesoscale DiscussionSPC96 min
Aug 5, 5:30 PM MDTSevere Thunderstorm WarningBOU45 min
Aug 7, 1:14 PM MDTMesoscale DiscussionSPC2 hr
Aug 7, 2:03 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 7, 2:57 PM MDTSevere Thunderstorm WarningBOU26 min
Aug 7, 3:35 PM MDTSevere Thunderstorm WarningBOU40 min
Aug 7, 3:57 PM MDTSevere Thunderstorm WarningBOU29 min
Aug 7, 4:50 PM MDTMesoscale DiscussionSPC115 min
Aug 8, 1:24 PM MDTMesoscale DiscussionSPC2 hr
Aug 8, 2:37 PM MDTSevere Thunderstorm WatchSPC7 hr
Aug 8, 3:53 PM MDTSevere Thunderstorm WarningBOU52 min
Aug 8, 4:17 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 8, 4:31 PM MDTTornado WarningBOU29 min
Aug 8, 5:12 PM MDTMesoscale DiscussionSPC2 hr
Aug 8, 5:36 PM MDTSevere Thunderstorm WarningBOU27 min
Aug 8, 5:54 PM MDTSevere Thunderstorm WarningBOU36 min
Aug 8, 5:55 PM MDTSevere Thunderstorm WarningBOU24 min
Aug 8, 6:06 PM MDTSevere Thunderstorm WarningBOU24 min
Aug 8, 6:13 PM MDTSevere Thunderstorm WarningBOU31 min
Aug 8, 9:47 PM MDTSpecial Weather StatementBOU43 min
Aug 8, 10:37 PM MDTSpecial Weather StatementBOU38 min
Aug 8, 10:50 PM MDTSevere Thunderstorm WarningBOU25 min
Aug 10, 3:38 PM MDTSpecial Weather StatementBOU37 min
Aug 12, 1:12 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 18, 2:12 PM MDTFire Weather WatchBOU24 hr
Aug 19, 2:02 PM MDTRed Flag WarningBOU30 hr
Aug 20, 2:02 PM MDTFire Weather WatchBOU13 hr
Aug 21, 2:44 AM MDTHeat AdvisoryBOU17 hr
Aug 21, 2:53 AM MDTRed Flag WarningBOU16 hr
Aug 22, 3:28 AM MDTHeat AdvisoryBOU17 hr
Aug 24, 1:53 PM MDTFlood WatchBOU30 hr
Aug 25, 7:59 AM MDTAreal Flood AdvisoryBOU3 hr
Aug 25, 1:44 PM MDTAreal Flood AdvisoryBOU3 hr
Aug 25, 1:58 PM MDTSpecial Weather StatementBOU47 min
Aug 25, 2:49 PM MDTSpecial Weather StatementBOU41 min
Aug 27, 6:44 PM MDTSpecial Weather StatementBOU61 min
Oct 2, 1:41 PM MDTMesoscale DiscussionSPC2 hr
Oct 2, 4:57 PM MDTSpecial Weather StatementBOU33 min
Oct 5, 2:04 PM MDTFreeze WatchBOU13 hr
Oct 6, 2:54 AM MDTFreeze WarningBOU30 hr
Oct 11, 2:16 AM MDTHigh Wind WatchBOU35 hr
Oct 12, 1:12 PM MDTFreeze WatchBOU15 hr
Oct 13, 4:06 AM MDTFreeze WarningBOU29 hr
Oct 27, 2:22 PM MDTWinter Weather AdvisoryBOU46 hr
Nov 12, 12:55 PM MSTRed Flag WarningBOU28 hr
Nov 22, 1:59 PM MSTWinter Weather AdvisoryBOU63 hr
Dec 22, 8:49 PM MSTWinter Weather AdvisoryBOU38 hr
Dec 23, 3:16 AM MSTWinter Storm WatchBOU11 hr
Dec 24, 8:28 PM MSTHigh Wind WatchBOU6 hr
Dec 25, 2:05 AM MSTBlizzard WarningBOU51 hr
Dec 26, 3:33 AM MSTMesoscale DiscussionSPC5 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 archive20222024

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.