Alert archive / Texas / Harris County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Harris County, Texas, 2011

31 severe thunderstorm warnings in 2011. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Harris County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Severe Thunderstorm Warnings
31
Busiest month
September11 severe thunderstorm warnings
Busiest day
September 29, 201110 severe thunderstorm warnings

Over time

By month

Warning verification

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

8 of 31 severe thunderstorm warnings covering Harris County in 2011 had a qualifying storm report inside them; 5 of 10 hail, wind and damage reports fell inside a warning, on average 13 minutes after it went out.

Harris County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings31874%1050%13 min

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Houston/Galveston, TX: severe thunderstorm warnings1284962%10172%22 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
Feb 1, 5:50 AM CSTSevere Thunderstorm WarningHGX40 min
Feb 1, 6:33 AM CSTSevere Thunderstorm WarningHGX57 min
Apr 4, 10:52 AM CDTSevere Thunderstorm WarningHGX16 min
May 12, 12:30 PM CDTSevere Thunderstorm WarningHGX45 min
May 12, 1:37 PM CDTSevere Thunderstorm WarningHGX53 min
May 26, 1:40 AM CDTSevere Thunderstorm WarningHGX24 min
Jun 5, 4:19 PM CDTSevere Thunderstorm WarningHGX41 min
Jun 5, 6:03 PM CDTSevere Thunderstorm WarningHGX42 min
Jun 5, 6:29 PM CDTSevere Thunderstorm WarningHGX46 min
Jun 5, 8:34 PM CDTSevere Thunderstorm WarningHGX41 min
Jun 6, 3:07 PM CDTSevere Thunderstorm WarningHGX38 min
Jun 6, 4:13 PM CDTSevere Thunderstorm WarningHGX27 min
Jun 6, 4:15 PM CDTSevere Thunderstorm WarningHGX45 min
Jul 5, 7:28 PM CDTSevere Thunderstorm WarningHGX32 min
Jul 5, 7:52 PM CDTSevere Thunderstorm WarningHGX53 min
Jul 6, 3:13 PM CDTSevere Thunderstorm WarningHGX26 min
Aug 24, 7:29 PM CDTSevere Thunderstorm WarningHGX46 min
Sep 27, 6:13 PM CDTSevere Thunderstorm WarningHGX47 min
Sep 29, 3:56 PM CDTSevere Thunderstorm WarningHGX49 min
Sep 29, 4:11 PM CDTSevere Thunderstorm WarningHGX49 min
Sep 29, 4:23 PM CDTSevere Thunderstorm WarningHGX37 min
Sep 29, 4:32 PM CDTSevere Thunderstorm WarningHGX28 min
Sep 29, 4:38 PM CDTSevere Thunderstorm WarningHGX52 min
Sep 29, 4:41 PM CDTSevere Thunderstorm WarningHGX49 min
Sep 29, 5:00 PM CDTSevere Thunderstorm WarningHGX45 min
Sep 29, 5:03 PM CDTSevere Thunderstorm WarningHGX42 min
Sep 29, 5:28 PM CDTSevere Thunderstorm WarningHGX27 min
Sep 29, 5:41 PM CDTSevere Thunderstorm WarningHGX40 min
Nov 8, 1:21 PM CSTSevere Thunderstorm WarningHGX39 min
Nov 15, 1:33 PM CSTSevere Thunderstorm WarningHGX27 min
Nov 15, 2:16 PM CSTSevere Thunderstorm WarningHGX29 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20102012

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.