Alert archive / Texas / Harris County / Flash Flood Warnings

Flash Flood Warnings in Harris County, Texas, 2014

20 flash flood warnings in 2014. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Harris County and its neighbors

Each county as a circle sized by its count in 2014. Tap one for its archive.

Flash Flood Warnings
20
Busiest month
September9 flash flood warnings
Busiest day
August 1, 20146 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.

9 of 21 flash flood warnings covering Harris County in 2014 had a flash flood report inside them; 11 of 24 flash flood reports fell inside a warning, on average 60 minutes after it went out.

Harris County, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings21957%2446%60 min

Each office's whole area, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Houston/Galveston, TX: flash flood warnings441468%4650%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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
May 26, 4:16 PM CDTFlash Flood WarningHGX119 min
May 26, 6:02 PM CDTFlash Flood WarningHGX3 hr
May 27, 4:30 PM CDTFlash Flood WarningHGX2 hr
May 28, 3:55 AM CDTFlash Flood WarningHGX3 hr
Jul 3, 5:36 PM CDTFlash Flood WarningHGX54 min
Jul 31, 11:03 PM CDTFlash Flood WarningHGX2 hr
Jul 31, 11:33 PM CDTFlash Flood WarningHGX3 hr
Jul 31, 11:57 PM CDTFlash Flood WarningHGX2 hr
Aug 1, 12:32 AM CDTFlash Flood WarningHGX118 min
Aug 1, 1:21 AM CDTFlash Flood WarningHGX54 min
Aug 1, 2:22 AM CDTFlash Flood WarningHGX113 min
Sep 17, 2:20 PM CDTFlash Flood WarningHGX115 min
Sep 18, 9:25 AM CDTFlash Flood WarningHGX65 min
Sep 18, 10:17 AM CDTFlash Flood WarningHGX4 hr
Sep 18, 2:37 PM CDTFlash Flood WarningHGX113 min
Sep 19, 5:00 AM CDTFlash Flood WarningHGX3 hr
Sep 19, 5:52 AM CDTFlash Flood WarningHGX113 min
Sep 19, 7:38 AM CDTFlash Flood WarningHGX3 hr
Sep 19, 7:46 AM CDTFlash Flood WarningHGX3 hr
Sep 19, 10:39 AM CDTFlash Flood WarningHGX81 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20132015

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.