Alert archive / Nevada / Douglas County / Flash Flood Warnings

Flash Flood Warnings in Douglas County, Nevada, 2020

5 flash flood warnings in 2020. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Douglas County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Flash Flood Warnings
5
Busiest month
July4 flash flood warnings
Busiest day
July 17, 20202 flash flood warnings

Over time

By month

Warning verification

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

0 of 5 flash flood warnings covering Douglas County in 2020 had a flash flood report inside them.

Douglas County, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings50100%0

Each office's whole area, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Reno, NV: flash flood warnings21290%560%53 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, Pacific Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jun 25, 5:26 PM PDTFlash Flood WarningREV3 hr
Jul 17, 3:24 PM PDTFlash Flood WarningREV86 min
Jul 17, 3:50 PM PDTFlash Flood WarningREV115 min
Jul 18, 5:40 PM PDTFlash Flood WarningREV87 min
Jul 21, 4:28 PM PDTFlash Flood WarningREV2 hr

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20192021

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.