Alert archive / Florida / Union County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Union County, Florida, 2010

9 severe thunderstorm warnings in 2010. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Union County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Severe Thunderstorm Warnings
9
Busiest month
January2 severe thunderstorm warnings
Busiest day
January 21, 20102 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.

5 of 9 severe thunderstorm warnings covering Union County in 2010 had a qualifying storm report inside them; 1 of 1 hail, wind and damage reports fell inside a warning, on average 19 minutes after it went out.

Union County, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings9544%1100%19 min

Each office's whole area, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Jacksonville, FL: severe thunderstorm warnings16311927%21974%17 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 21, 12:53 PM ESTSevere Thunderstorm WarningJAX52 min
Jan 21, 3:36 PM ESTSevere Thunderstorm WarningJAX39 min
Apr 25, 4:27 PM EDTSevere Thunderstorm WarningJAX25 min
Apr 25, 4:50 PM EDTSevere Thunderstorm WarningJAX25 min
May 23, 5:48 PM EDTSevere Thunderstorm WarningJAX42 min
Jun 6, 1:23 PM EDTSevere Thunderstorm WarningJAX39 min
Jun 20, 3:55 PM EDTSevere Thunderstorm WarningJAX50 min
Jul 28, 4:42 PM EDTSevere Thunderstorm WarningJAX48 min
Sep 27, 12:54 PM EDTSevere Thunderstorm WarningJAX51 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20092011

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.