Alert archive / Florida / Seminole County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Seminole County, Florida, 2012

13 severe thunderstorm warnings in 2012. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Seminole County and its neighbors

Each county as a circle sized by its count in 2012. Tap one for its archive.

Severe Thunderstorm Warnings
13
Busiest month
August4 severe thunderstorm warnings
Busiest day
August 3, 20122 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.

4 of 13 severe thunderstorm warnings covering Seminole County in 2012 had a qualifying storm report inside them; 11 of 12 hail, wind and damage reports fell inside a warning, on average 24 minutes after it went out.

Seminole County, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings13469%1292%24 min

Each office's whole area, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Melbourne, FL: severe thunderstorm warnings972673%10454%20 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
Apr 20, 6:36 PM EDTSevere Thunderstorm WarningMLB54 min
May 17, 8:00 PM EDTSevere Thunderstorm WarningMLB60 min
May 31, 5:30 PM EDTSevere Thunderstorm WarningMLB30 min
Jun 5, 2:41 PM EDTSevere Thunderstorm WarningMLB64 min
Jun 10, 7:29 PM EDTSevere Thunderstorm WarningMLB61 min
Jun 14, 2:25 PM EDTSevere Thunderstorm WarningMLB65 min
Jul 5, 7:23 PM EDTSevere Thunderstorm WarningMLB21 min
Jul 9, 3:25 PM EDTSevere Thunderstorm WarningMLB33 min
Jul 22, 4:04 PM EDTSevere Thunderstorm WarningMLB56 min
Aug 3, 2:40 PM EDTSevere Thunderstorm WarningMLB13 min
Aug 3, 2:50 PM EDTSevere Thunderstorm WarningMLB40 min
Aug 14, 4:33 PM EDTSevere Thunderstorm WarningMLB42 min
Aug 21, 3:25 PM EDTSevere Thunderstorm WarningMLB31 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20112013

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.