Alert archive / Idaho / Flash Flood Warnings

Flash Flood Warnings in Idaho, 2010

16 flash flood warnings in 2010. 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 2010. Tap one for its archive.

Flash Flood Warnings
16
Busiest month
June8 flash flood warnings
Busiest day
June 4, 20105 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.

1 of 16 flash flood warnings covering Idaho in 2010 had a flash flood report inside them; 3 of 10 flash flood reports fell inside a warning, on average 26 minutes after it went out.

Idaho, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings16194%1030%26 min

Each office's whole area, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Missoula, MT: flash flood warnings70100%20%
NWS Salt Lake City, UT: flash flood warnings702269%4154%45 min
NWS Spokane, WA: flash flood warnings30100%110%
NWS Boise, ID: flash flood warnings12375%1464%36 min
NWS Pocatello, ID: flash flood warnings40100%20%

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.

IssuedProductOfficeCountiesLasted
Apr 21, 11:42 AM MDTFlash Flood WarningPIHBlaine3 hr
Jun 4, 11:42 AM MDTFlash Flood WarningBOIAdams, Washington108 min
Jun 4, 1:17 PM MDTFlash Flood WarningBOIAdams, Gem, Valley, Washington104 min
Jun 4, 1:46 PM MDTFlash Flood WarningPIHCuster6 hr
Jun 4, 1:57 PM MDTFlash Flood WarningBOIGem, Payette, Washington67 min
Jun 4, 2:21 PM MDTFlash Flood WarningBOIBoise, Gem, Valley60 min
Jun 4, 6:35 PM MDTFlash Flood WarningPIHBlaine, Custer3 hr
Jun 9, 5:06 PM MDTFlash Flood WarningBOIWashington114 min
Jun 15, 5:54 PM MDTFlash Flood WarningPIHBannock, Caribou6 hr
Aug 5, 4:56 PM MDTFlash Flood WarningBOIBoise2 hr
Aug 5, 6:05 PM MDTFlash Flood WarningBOIOwyhee59 min
Aug 5, 6:45 PM MDTFlash Flood WarningBOIBoise2 hr
Aug 5, 8:11 PM MDTFlash Flood WarningMSOIdaho61 min
Aug 6, 4:22 PM MDTFlash Flood WarningMSOLemhi98 min
Aug 6, 5:56 PM MDTFlash Flood WarningMSOLemhi2 hr
Aug 6, 8:07 PM MDTFlash Flood WarningBOICanyon, Gem, Payette, Washington83 min

By county

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

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20092011

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.