Alert archive / Texas / Harris County / Flash Flood Warnings

Flash Flood Warnings in Harris County, Texas, 2015

56 flash flood warnings in 2015. 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 2015. Tap one for its archive.

Flash Flood Warnings
56
Busiest month
May24 flash flood warnings
Busiest day
May 26, 201510 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.

38 of 56 flash flood warnings covering Harris County in 2015 had a flash flood report inside them; 70 of 83 flash flood reports fell inside a warning, on average 64 minutes after it went out.

Harris County, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings563832%8384%64 min

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Houston/Galveston, TX: flash flood warnings1387347%20778%65 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
Jan 22, 1:00 PM CSTFlash Flood WarningHGX2 hr
Mar 21, 3:05 PM CDTFlash Flood WarningHGX3 hr
Apr 16, 4:57 PM CDTFlash Flood WarningHGX3 hr
Apr 16, 8:06 PM CDTFlash Flood WarningHGX114 min
Apr 16, 9:03 PM CDTFlash Flood WarningHGX117 min
Apr 16, 10:54 PM CDTFlash Flood WarningHGX3 hr
Apr 17, 12:00 AM CDTFlash Flood WarningHGX2 hr
Apr 17, 7:55 PM CDTFlash Flood WarningHGX3 hr
Apr 17, 8:25 PM CDTFlash Flood WarningHGX3 hr
Apr 17, 10:57 PM CDTFlash Flood WarningHGX2 hr
Apr 17, 11:29 PM CDTFlash Flood WarningHGX91 min
May 12, 10:25 PM CDTFlash Flood WarningHGX3 hr
May 12, 11:08 PM CDTFlash Flood WarningHGX2 hr
May 13, 12:19 AM CDTFlash Flood WarningHGX56 min
May 13, 1:11 AM CDTFlash Flood WarningHGX3 hr
May 13, 1:52 AM CDTFlash Flood WarningHGX2 hr
May 13, 4:14 AM CDTFlash Flood WarningHGX3 hr
May 13, 4:15 AM CDTFlash Flood WarningHGX60 min
May 13, 5:15 AM CDTFlash Flood WarningHGX4 hr
May 18, 5:43 AM CDTFlash Flood WarningHGX2 hr
May 25, 8:31 PM CDTFlash Flood WarningHGX3 hr
May 25, 8:35 PM CDTFlash Flood WarningHGX3 hr
May 25, 8:54 PM CDTFlash Flood WarningHGX3 hr
May 25, 9:11 PM CDTFlash Flood WarningHGX3 hr
May 25, 10:52 PM CDTFlash Flood Warning EmergencyHGX113 min
May 25, 11:40 PM CDTFlash Flood WarningHGX3 hr
May 26, 12:35 AM CDTFlash Flood Warning EmergencyHGX115 min
May 26, 2:21 AM CDTFlash Flood Warning EmergencyHGX114 min
May 26, 2:30 AM CDTFlash Flood Warning EmergencyHGX3 hr
May 26, 4:10 AM CDTFlash Flood Warning EmergencyHGX110 min
May 27, 5:31 AM CDTFlash Flood WarningHGX3 hr
May 27, 5:45 AM CDTFlash Flood WarningHGX3 hr
May 27, 6:14 AM CDTFlash Flood WarningHGX3 hr
May 30, 4:37 PM CDTFlash Flood WarningHGX113 min
May 30, 5:30 PM CDTFlash Flood WarningHGX2 hr
Jun 13, 10:27 AM CDTFlash Flood WarningHGX3 hr
Jun 17, 2:50 AM CDTFlash Flood WarningHGX3 hr
Jun 17, 3:08 AM CDTFlash Flood WarningHGX3 hr
Jun 27, 9:43 PM CDTFlash Flood WarningHGX3 hr
Jun 27, 10:10 PM CDTFlash Flood WarningHGX2 hr
Jun 28, 12:33 AM CDTFlash Flood WarningHGX117 min
Jun 28, 5:43 AM CDTFlash Flood WarningHGX2 hr
Jun 28, 7:40 AM CDTFlash Flood WarningHGX3 hr
Jun 30, 5:58 PM CDTFlash Flood WarningHGX92 min
Aug 19, 2:06 PM CDTFlash Flood WarningHGX114 min
Aug 20, 8:56 AM CDTFlash Flood WarningHGX2 hr
Sep 11, 9:01 AM CDTFlash Flood WarningHGX119 min
Oct 24, 7:20 PM CDTFlash Flood WarningHGX3 hr
Oct 24, 10:15 PM CDTFlash Flood WarningHGX3 hr
Oct 25, 1:11 AM CDTFlash Flood WarningHGX3 hr
Oct 31, 2:51 AM CDTFlash Flood WarningHGX3 hr
Oct 31, 3:59 AM CDTFlash Flood WarningHGX3 hr
Oct 31, 6:07 AM CDTFlash Flood WarningHGX53 min
Oct 31, 7:03 AM CDTFlash Flood WarningHGX3 hr
Oct 31, 9:55 AM CDTFlash Flood WarningHGX110 min
Oct 31, 11:51 AM CDTFlash Flood WarningHGX114 min

The busiest days

Days with the most alerts issued, by UTC date.

  1. May 26, 201510flash flood warnings
  2. May 13, 20158flash flood warnings
  3. October 31, 20156flash flood warnings
  4. June 28, 20155flash flood warnings
  5. April 17, 20154flash flood warnings
  6. April 18, 20154flash flood warnings
  7. May 27, 20153flash flood warnings
  8. October 25, 20153flash flood warnings
  9. May 30, 20152flash flood warnings
  10. June 17, 20152flash flood warnings

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.