Flash Flood Warnings in Mohave County, Arizona

1,260 flash flood warnings since 1986. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Mohave County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Flash Flood Warnings: 1,260
Busiest year: 2022161 flash flood warnings
Average year: 32over 39 years on file

Over time

By year

Before October 2007 these were issued for whole counties, and a storm crossing three counties was often three warnings; since then one polygon follows the storm. The count changed with the practice, not only with the weather.

Warning verification

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

From 2008 to 2025, 70% of flash flood reports in Mohave County fell inside a flash flood warning issued on average 80 minutes before, and 65% of the flash flood warnings had no report inside them.

Flash flood warnings by year

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
2008	33	7	79%	13	54%	48 min
2009	12	3	75%	7	43%	74 min
2010	34	13	62%	21	71%	52 min
2011	29	6	79%	7	57%	51 min
2012	79	24	70%	35	69%	52 min
2013	103	35	66%	77	71%	65 min
2014	78	44	44%	91	81%	70 min
2015	54	26	52%	40	80%	84 min
2016	57	17	70%	37	59%	92 min
2017	46	15	67%	31	81%	135 min
2018	73	26	64%	91	67%	78 min
2019	28	10	64%	41	63%	101 min
2020	14	1	93%	5	0%
2021	66	20	70%	71	70%	98 min
2022	172	72	58%	251	69%	83 min
2023	45	14	69%	37	57%	77 min
2024	32	6	81%	6	100%	100 min
2025	47	15	68%	44	82%	62 min

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

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 latest flash flood warnings

The most recent on file, newest first.

Issued	Product	Office	Lasted
Sep 16, 5:52 PM MST	Flash Flood Warning Considerable damage threat	VEF	4 hr
Sep 16, 5:36 PM MST	Flash Flood Warning Considerable damage threat	VEF	4 hr
Sep 1, 11:40 AM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr
Aug 31, 5:23 PM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr
Aug 30, 7:21 PM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr
Aug 14, 4:19 PM MST	Flash Flood Warning Considerable damage threat	VEF	5 hr
Aug 14, 4:00 PM MST	Flash Flood Warning Considerable damage threat	VEF	6 hr
Aug 14, 3:09 PM MST	Flash Flood Warning Considerable damage threat	VEF	7 hr
Aug 14, 10:18 AM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr
Aug 12, 8:04 PM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr
Aug 12, 4:00 PM MST	Flash Flood Warning Considerable damage threat	VEF	4 hr
Aug 12, 8:46 AM MST	Flash Flood Warning Considerable damage threat	VEF	3 hr

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive

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.