Alert archive / Minnesota / Lyon County

Weather alerts in Lyon County, Minnesota, 2009

86 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Lyon County and its neighbors

Each county as a circle sized by its count in 2009. Tap one for its archive.

Alerts
86
Warnings
16
Watches
14
Advisories
35
Busiest month
January16 alerts
Busiest day
August 8, 20095 alerts

Over time

By month

Warning verification

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

Lyon County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings990%8100%15 min
Flash flood warnings00

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Sioux Falls, SD: tornado warnings491667%2378%21 min
NWS Sioux Falls, SD: severe thunderstorm warnings23217226%37481%19 min
NWS Sioux Falls, SD: flash flood warnings251828%3488%49 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 2, 3:55 PM CSTWinter Weather AdvisoryFSD29 hr
Jan 3, 12:34 PM CSTMesoscale DiscussionSPC6 hr
Jan 3, 8:56 PM CSTWind Chill AdvisoryFSD13 hr
Jan 8, 4:02 AM CSTWinter Weather AdvisoryFSD24 hr
Jan 11, 4:33 AM CSTBlizzard WatchFSD24 hr
Jan 11, 2:50 PM CSTWinter Weather AdvisoryFSD30 hr
Jan 12, 4:18 AM CSTBlizzard WarningFSD16 hr
Jan 12, 9:20 AM CSTWinter Weather AdvisoryFSD11 hr
Jan 12, 10:56 AM CSTMesoscale DiscussionSPC6 hr
Jan 12, 6:40 PM CSTWind Chill AdvisoryFSD11 hr
Jan 13, 10:42 AM CSTWinter Weather AdvisoryFSD11 hr
Jan 13, 3:17 PM CSTWind Chill AdvisoryFSD33 hr
Jan 14, 3:39 AM CSTWind Chill WarningFSD26 hr
Jan 17, 7:38 AM CSTWinter Weather AdvisoryFSD3 hr
Jan 19, 6:41 PM CSTWinter Weather AdvisoryFSD7 hr
Jan 23, 3:33 AM CSTWind Chill AdvisoryFSD32 hr
Feb 2, 3:00 PM CSTWind Chill AdvisoryFSD19 hr
Feb 20, 3:59 AM CSTWinter Weather AdvisoryFSD17 hr
Feb 24, 4:11 PM CSTWinter Storm WatchFSD23 hr
Feb 25, 4:15 AM CSTWinter Storm WarningFSD41 hr
Feb 26, 6:33 AM CSTMesoscale DiscussionSPC5 hr
Feb 26, 4:04 PM CSTWind Chill AdvisoryFSD18 hr
Mar 8, 12:56 PM CDTWinter Storm WatchFSD27 hr
Mar 9, 3:45 AM CDTBlizzard WatchFSD12 hr
Mar 9, 10:01 AM CDTDense Fog AdvisoryFSD119 min
Mar 9, 4:05 PM CDTWinter Storm WarningFSD12 hr
Mar 9, 6:46 PM CDTWinter Weather AdvisoryFSD4 hr
Mar 10, 3:40 AM CDTWinter Weather AdvisoryFSD23 hr
Mar 10, 2:51 PM CDTWind Chill AdvisoryFSD21 hr
Mar 22, 3:44 AM CDTWind AdvisoryFSD44 hr
Mar 22, 11:28 PM CDTMesoscale DiscussionSPC3 hr
Mar 28, 3:59 PM CDTWinter Storm WatchFSD36 hr
Mar 30, 4:08 AM CDTWinter Weather AdvisoryFSD41 hr
Mar 30, 11:16 AM CDTWind AdvisoryFSD8 hr
Mar 31, 1:26 PM CDTMesoscale DiscussionSPC3 hr
Apr 3, 9:45 PM CDTWinter Weather AdvisoryFSD39 hr
Apr 20, 10:33 AM CDTWind AdvisoryFSD8 hr
Apr 23, 3:29 AM CDTWind AdvisoryFSD16 hr
May 12, 3:34 AM CDTWind AdvisoryFSD17 hr
May 12, 3:49 PM CDTWind AdvisoryFSD30 hr
May 12, 8:42 PM CDTMesoscale DiscussionSPC93 min
May 15, 1:17 PM CDTMesoscale DiscussionSPC58 min
May 19, 3:18 PM CDTWind AdvisoryFSD28 hr
Jun 16, 6:54 PM CDTSevere Thunderstorm WarningFSD51 min
Jun 16, 7:44 PM CDTSevere Thunderstorm WarningFSD31 min
Jun 16, 8:41 PM CDTSevere Thunderstorm WarningFSD49 min
Jun 18, 6:52 PM CDTMesoscale DiscussionSPC113 min
Jun 18, 10:18 PM CDTSevere Thunderstorm WarningFSD42 min
Jun 23, 8:01 AM CDTSevere Thunderstorm WatchSPC6 hr
Jun 23, 11:31 AM CDTMesoscale DiscussionSPC89 min
Jun 24, 2:12 PM CDTMesoscale DiscussionSPC93 min
Jun 24, 6:16 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 26, 11:46 PM CDTMesoscale DiscussionSPC59 min
Jul 7, 2:13 PM CDTSevere Thunderstorm WatchSPC8 hr
Jul 7, 3:56 PM CDTMesoscale DiscussionSPC34 min
Jul 7, 5:42 PM CDTSevere Thunderstorm WarningFSD48 min
Jul 7, 6:33 PM CDTMesoscale DiscussionSPC27 min
Jul 9, 3:07 AM CDTMesoscale DiscussionSPC83 min
Jul 9, 12:07 PM CDTFlash Flood WatchFSD21 hr
Jul 9, 6:34 PM CDTMesoscale DiscussionSPC86 min
Jul 14, 1:42 PM CDTMesoscale DiscussionSPC93 min
Jul 14, 2:40 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 21, 12:20 PM CDTMesoscale DiscussionSPC55 min
Jul 31, 7:43 PM CDTMesoscale DiscussionSPC2 hr
Aug 2, 8:32 PM CDTMesoscale DiscussionSPC28 min
Aug 2, 8:41 PM CDTSevere Thunderstorm WatchSPC6 hr
Aug 2, 8:44 PM CDTSevere Thunderstorm WarningFSD31 min
Aug 2, 9:17 PM CDTSevere Thunderstorm WarningFSD13 min
Aug 8, 12:16 PM CDTMesoscale DiscussionSPC29 min
Aug 8, 12:47 PM CDTTornado WatchSPC5 hr
Aug 8, 3:15 PM CDTSevere Thunderstorm WarningFSD30 min
Aug 8, 3:27 PM CDTMesoscale DiscussionSPC33 min
Aug 8, 3:42 PM CDTSevere Thunderstorm WarningFSD23 min
Sep 26, 2:26 PM CDTWind AdvisoryFSD30 hr
Sep 28, 3:20 PM CDTFrost AdvisoryFSD18 hr
Oct 8, 3:43 AM CDTFreeze WarningFSD28 hr
Oct 10, 3:16 PM CDTWinter Storm WatchFSD24 hr
Dec 7, 3:39 AM CSTWinter Weather AdvisoryFSD49 hr
Dec 8, 1:33 PM CSTBlizzard WarningFSD25 hr
Dec 9, 4:10 AM CSTWind Chill AdvisoryFSD30 hr
Dec 13, 6:13 AM CSTWind Chill AdvisoryFSD4 hr
Dec 14, 2:56 PM CSTWind Chill AdvisoryFSD18 hr
Dec 21, 2:02 PM CSTWinter Storm WatchFSD24 hr
Dec 22, 4:30 AM CSTWinter Storm WarningFSD4 days
Dec 23, 4:48 AM CSTWinter Weather AdvisoryFSD13 hr
Dec 26, 3:56 AM CSTWinter Weather AdvisoryFSD20 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 archive20082010

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.