Alert archive / Wisconsin / Jefferson County

Weather alerts in Jefferson County, Wisconsin, 2023

105 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Jefferson County and its neighbors

Each county as a circle sized by its count in 2023. Tap one for its archive.

Alerts
105
Warnings
32
Watches
14
Advisories
26
Busiest month
April29 alerts
Busiest day
April 20, 20237 alerts

Over time

By month

Warning verification

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

2 of 4 tornado warnings covering Jefferson County in 2023 had a tornado report inside them; 2 of 5 tornado reports fell inside a warning, on average 34 minutes after it went out.

Jefferson County, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings4250%540%34 min
Severe thunderstorm warnings211243%1883%24 min
Flash flood warnings00

Each office's whole area, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Milwaukee, WI: tornado warnings13469%2646%16 min
NWS Milwaukee, WI: severe thunderstorm warnings1025447%15671%23 min
NWS Milwaukee, WI: flash flood warnings7271%667%23 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 1, 5:06 PM CSTDense Fog AdvisoryMKX13 hr
Jan 3, 5:52 PM CSTDense Fog AdvisoryMKX11 hr
Jan 11, 12:08 AM CSTDense Fog AdvisoryMKX3 hr
Jan 11, 4:54 AM CSTWinter Weather AdvisoryMKX4 hr
Jan 18, 2:49 AM CSTWinter Weather AdvisoryMKX30 hr
Jan 27, 2:16 PM CSTWinter Weather AdvisoryMKX37 hr
Jan 30, 2:14 PM CSTWind Chill AdvisoryMKX20 hr
Feb 2, 3:05 AM CSTWind Chill AdvisoryMKX32 hr
Feb 8, 3:19 AM CSTWinter Weather AdvisoryMKX39 hr
Feb 15, 2:34 AM CSTWinter Storm WatchMKX11 hr
Feb 15, 1:57 PM CSTWinter Storm WarningMKX34 hr
Feb 16, 8:02 AM CSTMesoscale DiscussionSPC6 hr
Feb 20, 2:53 PM CSTWinter Storm WatchMKX23 hr
Feb 21, 1:53 PM CSTWinter Storm WarningMKX46 hr
Feb 22, 8:46 AM CSTMesoscale DiscussionSPC5 hr
Feb 22, 3:27 PM CSTMesoscale DiscussionSPC4 hr
Feb 23, 1:50 AM CSTWinter Weather AdvisoryMKX10 hr
Mar 8, 3:31 AM CSTWinter Storm WatchMKX11 hr
Mar 8, 2:12 PM CSTWinter Weather AdvisoryMKX43 hr
Mar 24, 2:47 AM CDTWinter Weather AdvisoryMKX32 hr
Mar 24, 2:38 PM CDTWinter Storm WarningMKX25 hr
Mar 25, 3:47 AM CDTMesoscale DiscussionSPC4 hr
Mar 25, 8:54 AM CDTMesoscale DiscussionSPC4 hr
Mar 31, 2:07 PM CDTMesoscale DiscussionSPC83 min
Mar 31, 2:36 PM CDTTornado WatchSPC7 hr
Mar 31, 7:11 PM CDTSevere Thunderstorm WarningMKX64 min
Mar 31, 7:35 PM CDTTornado WarningMKX40 min
Mar 31, 7:49 PM CDTTornado WarningMKX41 min
Mar 31, 7:50 PM CDTSevere Thunderstorm WarningMKX55 min
Mar 31, 7:54 PM CDTMesoscale DiscussionSPC2 hr
Mar 31, 8:15 PM CDTTornado Warning Tornado observedMKX17 min
Apr 4, 8:00 AM CDTMesoscale DiscussionSPC3 hr
Apr 4, 12:41 PM CDTFlood WatchMKX15 hr
Apr 4, 10:13 PM CDTSevere Thunderstorm WarningMKX47 min
Apr 4, 10:59 PM CDTSevere Thunderstorm WarningMKX46 min
Apr 5, 1:51 AM CDTSpecial Weather StatementMKX54 min
Apr 5, 5:32 AM CDTSevere Thunderstorm WarningMKX21 min
Apr 11, 2:45 PM CDTFire Weather WatchMKX12 hr
Apr 12, 3:11 AM CDTRed Flag WarningMKX17 hr
Apr 12, 2:30 PM CDTFire Weather WatchMKX13 hr
Apr 13, 3:03 AM CDTRed Flag WarningMKX17 hr
Apr 15, 2:46 PM CDTSpecial Weather StatementMKX29 min
Apr 15, 10:56 PM CDTSpecial Weather StatementMKX34 min
Apr 15, 11:11 PM CDTSpecial Weather StatementMKX34 min
Apr 19, 1:50 PM CDTSevere Thunderstorm WarningMKX25 min
Apr 19, 2:14 PM CDTSevere Thunderstorm WarningMKX19 min
Apr 19, 2:42 PM CDTMesoscale DiscussionSPC2 hr
Apr 20, 4:18 AM CDTSpecial Weather StatementMKX27 min
Apr 20, 1:50 PM CDTMesoscale DiscussionSPC85 min
Apr 20, 2:06 PM CDTTornado WatchSPC6 hr
Apr 20, 3:41 PM CDTMesoscale DiscussionSPC94 min
Apr 20, 4:16 PM CDTSevere Thunderstorm WarningMKX33 min
Apr 20, 4:48 PM CDTSpecial Weather StatementMKX27 min
Apr 20, 5:23 PM CDTMesoscale DiscussionSPC97 min
May 31, 12:53 PM CDTSpecial Weather StatementMKX22 min
Jun 29, 3:03 AM CDTSpecial Weather StatementMKX42 min
Jul 5, 12:49 PM CDTMesoscale DiscussionSPC116 min
Jul 5, 12:57 PM CDTSevere Thunderstorm WarningMKX48 min
Jul 5, 1:48 PM CDTSevere Thunderstorm WarningMKX27 min
Jul 5, 2:12 PM CDTSpecial Weather StatementMKX48 min
Jul 5, 2:19 PM CDTSevere Thunderstorm WarningMKX21 min
Jul 13, 7:04 PM CDTMesoscale DiscussionSPC56 min
Jul 14, 2:38 PM CDTMesoscale DiscussionSPC2 hr
Jul 14, 3:52 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 22, 4:26 PM CDTSpecial Weather StatementMKX34 min
Jul 22, 5:44 PM CDTSevere Thunderstorm WarningMKX46 min
Jul 22, 6:24 PM CDTSpecial Weather StatementMKX51 min
Jul 26, 11:24 AM CDTSevere Thunderstorm WarningMKX51 min
Jul 26, 2:21 PM CDTHeat AdvisoryMKX30 hr
Jul 28, 3:58 AM CDTHeat AdvisoryMKX16 hr
Jul 28, 6:19 PM CDTMesoscale DiscussionSPC116 min
Jul 28, 6:27 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 28, 9:27 PM CDTSevere Thunderstorm Warning Considerable damage threatMKX63 min
Jul 28, 9:44 PM CDTTornado WarningMKX46 min
Jul 28, 9:44 PM CDTMesoscale DiscussionSPC2 hr
Jul 28, 9:59 PM CDTSevere Thunderstorm Warning Considerable damage threatMKX61 min
Aug 11, 6:42 PM CDTMesoscale DiscussionSPC63 min
Aug 11, 7:08 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 11, 9:59 PM CDTSpecial Weather StatementMKX46 min
Aug 13, 2:09 PM CDTFlood WatchMKX33 hr
Aug 19, 3:49 AM CDTHeat AdvisoryMKX40 hr
Aug 20, 2:15 PM CDTExcessive Heat WatchMKX61 hr
Aug 22, 3:20 AM CDTExcessive Heat WarningMKX64 hr
Aug 24, 2:46 PM CDTMesoscale DiscussionSPC119 min
Aug 24, 4:49 PM CDTSevere Thunderstorm WarningMKX41 min
Aug 24, 5:04 PM CDTSevere Thunderstorm WarningMKX41 min
Aug 24, 5:06 PM CDTSevere Thunderstorm WatchSPC4 hr
Aug 24, 5:26 PM CDTSevere Thunderstorm WarningMKX49 min
Aug 24, 6:08 PM CDTSevere Thunderstorm WarningMKX52 min
Aug 24, 6:33 PM CDTSevere Thunderstorm WarningMKX42 min
Sep 6, 3:38 PM CDTSpecial Weather StatementMKX52 min
Sep 6, 4:00 PM CDTSpecial Weather StatementMKX45 min
Sep 9, 2:01 AM CDTDense Fog AdvisoryMKX8 hr
Sep 13, 1:54 AM CDTDense Fog AdvisoryMKX5 hr
Sep 29, 1:17 AM CDTDense Fog AdvisoryMKX9 hr
Oct 8, 2:10 PM CDTFrost AdvisoryMKX19 hr
Oct 17, 12:18 AM CDTFrost AdvisoryMKX7 hr
Oct 19, 7:00 AM CDTDense Fog AdvisoryMKX2 hr
Oct 21, 2:32 PM CDTFrost AdvisoryMKX18 hr
Oct 23, 3:46 PM CDTSevere Thunderstorm WarningMKX44 min
Oct 29, 2:43 AM CDTFreeze WarningMKX31 hr
Dec 16, 7:46 PM CSTDense Fog AdvisoryMKX10 hr
Dec 23, 1:02 AM CSTDense Fog AdvisoryMKX10 hr
Dec 23, 11:04 AM CSTDense Fog AdvisoryMKX22 hr
Dec 30, 6:04 PM CSTWinter Weather AdvisoryMKX18 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20222024

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.