Alert archive / Florida / Hillsborough County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Hillsborough County, Florida, 2011

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

Hillsborough County and its neighbors

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

Severe Thunderstorm Warnings
24
Busiest month
March9 severe thunderstorm warnings
Busiest day
March 31, 20119 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.

13 of 24 severe thunderstorm warnings covering Hillsborough County in 2011 had a qualifying storm report inside them; 4 of 9 hail, wind and damage reports fell inside a warning, on average 30 minutes after it went out.

Hillsborough County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings241346%944%30 min

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Tampa Bay, FL: severe thunderstorm warnings913858%11367%15 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, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 10, 12:00 PM ESTSevere Thunderstorm WarningTBW30 min
Jan 17, 10:10 AM ESTSevere Thunderstorm WarningTBW35 min
Jan 25, 5:00 PM ESTSevere Thunderstorm WarningTBW60 min
Mar 31, 6:23 AM EDTSevere Thunderstorm WarningTBW52 min
Mar 31, 7:53 AM EDTSevere Thunderstorm WarningTBW52 min
Mar 31, 11:22 AM EDTSevere Thunderstorm WarningTBW38 min
Mar 31, 11:35 AM EDTSevere Thunderstorm WarningTBW40 min
Mar 31, 11:57 AM EDTSevere Thunderstorm WarningTBW33 min
Mar 31, 12:25 PM EDTSevere Thunderstorm WarningTBW35 min
Mar 31, 1:29 PM EDTSevere Thunderstorm WarningTBW31 min
Mar 31, 4:39 PM EDTSevere Thunderstorm WarningTBW36 min
Mar 31, 6:03 PM EDTSevere Thunderstorm WarningTBW29 min
Apr 5, 7:47 AM EDTSevere Thunderstorm WarningTBW43 min
Apr 5, 8:57 AM EDTSevere Thunderstorm WarningTBW48 min
May 14, 1:54 PM EDTSevere Thunderstorm WarningTBW36 min
May 14, 2:27 PM EDTSevere Thunderstorm WarningTBW48 min
May 14, 3:41 PM EDTSevere Thunderstorm WarningTBW34 min
May 15, 4:58 AM EDTSevere Thunderstorm WarningTBW22 min
Jun 15, 4:12 PM EDTSevere Thunderstorm WarningTBW33 min
Jun 23, 7:46 PM EDTSevere Thunderstorm WarningTBW44 min
Aug 9, 2:49 PM EDTSevere Thunderstorm WarningTBW41 min
Sep 5, 7:46 PM EDTSevere Thunderstorm WarningTBW29 min
Sep 5, 8:38 PM EDTSevere Thunderstorm WarningTBW37 min
Sep 7, 3:10 AM EDTSevere Thunderstorm WarningTBW35 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.