Alert archive / Colorado / Flash Flood Warnings / 2026

Flash Flood Warnings in Colorado, September 2026

27 flash flood warnings in September 2026. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of flash flood warnings reaches back to 1986.

Flash Flood Warnings by county

Each county as a circle sized by its count in September 2026. Tap one for its archive.

Flash Flood Warnings: 27
Busiest day: September 14, 20267 flash flood warnings

Over time

By day

Days in UTC, the clock the archive keeps.

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.

Issued	Product	Office	Counties	Lasted
Aug 31, 7:45 PM MDT	Flash Flood Warning	PUB	Kiowa	3 hr
Sep 1, 3:46 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Mesa	119 min
Sep 2, 12:37 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Mesa	3 hr
Sep 13, 8:25 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr
Sep 14, 5:42 AM MDT	Flash Flood Warning Considerable damage threat	GJT	Dolores	2 hr
Sep 14, 2:26 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	2 hr
Sep 14, 2:37 PM MDT	Flash Flood Warning Considerable damage threat	GJT	San Miguel	3 hr
Sep 14, 4:05 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Archuleta, La Plata	4 hr
Sep 14, 4:11 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Pitkin	4 hr
Sep 14, 5:14 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Archuleta	3 hr
Sep 15, 2:24 PM MDT	Flash Flood Warning	GJT	Garfield	3 hr
Sep 15, 2:42 PM MDT	Flash Flood Warning	GJT	San Miguel	3 hr
Sep 15, 6:25 PM MDT	Flash Flood Warning	GJT	Mesa	3 hr
Sep 16, 12:51 AM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	114 min
Sep 16, 1:05 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr
Sep 16, 9:17 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Gunnison, Hinsdale, Ouray	3 hr
Sep 16, 9:45 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Mesa	3 hr
Sep 18, 4:13 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Mesa	3 hr
Sep 18, 4:52 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Moffat, Rio Blanco	5 hr
Sep 19, 1:09 AM MDT	Flash Flood Warning Considerable damage threat	GJT	Dolores	2 hr
Sep 19, 1:29 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr
Sep 19, 1:38 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Mesa	3 hr
Sep 19, 6:01 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr
Sep 19, 6:19 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Garfield	3 hr
Sep 22, 1:38 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Dolores	2 hr
Sep 22, 7:33 PM MDT	Flash Flood Warning	BOU	Arapahoe, Douglas	79 min
Sep 25, 2:07 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr

By county

Every county with at least one alert. A county page lists each alert that covered it.

Nearby

Alerts in force now Tornadoes on record The radar archive 2025

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.