Alert archive / Texas / Jefferson County / Flash Flood Warnings

Flash Flood Warnings in Jefferson County, Texas, 2015

20 flash flood warnings in 2015. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Jefferson County and its neighbors

Each county as a circle sized by its count in 2015. Tap one for its archive.

Flash Flood Warnings
20
Busiest month
June6 flash flood warnings
Busiest day
March 21, 20155 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 20 flash flood warnings covering Jefferson County in 2015 had a flash flood report inside them; 9 of 19 flash flood reports fell inside a warning, on average 47 minutes after it went out.

Jefferson County, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings20955%1947%47 min

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Lake Charles, LA: flash flood warnings603443%9276%81 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
Mar 21, 10:56 AM CDTFlash Flood WarningLCH109 min
Mar 21, 12:32 PM CDTFlash Flood WarningLCH88 min
Mar 21, 12:48 PM CDTFlash Flood WarningLCH3 hr
Mar 21, 2:02 PM CDTFlash Flood WarningLCH3 hr
Mar 21, 3:48 PM CDTFlash Flood WarningLCH117 min
Apr 16, 1:15 PM CDTFlash Flood WarningLCH6 hr
Apr 16, 7:00 PM CDTFlash Flood WarningLCH3 hr
Apr 16, 9:59 PM CDTFlash Flood WarningLCH3 hr
May 12, 6:25 PM CDTFlash Flood WarningLCH2 hr
May 21, 1:35 PM CDTFlash Flood WarningLCH3 hr
May 25, 10:31 PM CDTFlash Flood WarningLCH4 hr
May 26, 2:31 AM CDTFlash Flood WarningLCH3 hr
Jun 17, 1:42 PM CDTFlash Flood WarningLCH3 hr
Jun 17, 3:47 PM CDTFlash Flood WarningLCH3 hr
Jun 17, 4:47 PM CDTFlash Flood WarningLCH3 hr
Jun 17, 7:44 PM CDTFlash Flood WarningLCH91 min
Jun 17, 8:27 PM CDTFlash Flood WarningLCH63 min
Jun 17, 9:28 PM CDTFlash Flood WarningLCH3 hr
Oct 31, 12:47 PM CDTFlash Flood WarningLCH6 hr
Nov 7, 6:20 AM CSTFlash Flood WarningLCH3 hr

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20142016

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.