Alert archive / Wyoming / Platte County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Platte County, Wyoming, 2009

27 severe thunderstorm warnings in 2009. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Platte County and its neighbors

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

Severe Thunderstorm Warnings
27
Busiest month
July16 severe thunderstorm warnings
Busiest day
July 2, 20094 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.

11 of 27 severe thunderstorm warnings covering Platte County in 2009 had a qualifying storm report inside them; 15 of 24 hail, wind and damage reports fell inside a warning, on average 25 minutes after it went out.

Platte County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings271159%2463%25 min

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Cheyenne, WY: severe thunderstorm warnings1868654%22766%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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
May 30, 3:08 PM MDTSevere Thunderstorm WarningCYS24 min
Jun 4, 4:12 PM MDTSevere Thunderstorm WarningCYS48 min
Jun 5, 2:47 PM MDTSevere Thunderstorm WarningCYS58 min
Jun 5, 3:06 PM MDTSevere Thunderstorm WarningCYS54 min
Jun 5, 8:41 PM MDTSevere Thunderstorm WarningCYS49 min
Jun 11, 2:17 PM MDTSevere Thunderstorm WarningCYS58 min
Jun 13, 5:23 PM MDTSevere Thunderstorm WarningCYS45 min
Jun 13, 5:24 PM MDTSevere Thunderstorm WarningCYS66 min
Jun 14, 1:00 PM MDTSevere Thunderstorm WarningCYS23 min
Jun 23, 4:58 PM MDTSevere Thunderstorm WarningCYS62 min
Jul 1, 6:05 PM MDTSevere Thunderstorm WarningCYS55 min
Jul 2, 3:44 PM MDTSevere Thunderstorm WarningCYS41 min
Jul 2, 4:02 PM MDTSevere Thunderstorm WarningCYS58 min
Jul 2, 5:02 PM MDTSevere Thunderstorm WarningCYS58 min
Jul 2, 6:33 PM MDTSevere Thunderstorm WarningCYS39 min
Jul 5, 3:05 PM MDTSevere Thunderstorm WarningCYS40 min
Jul 5, 3:34 PM MDTSevere Thunderstorm WarningCYS30 min
Jul 6, 3:45 PM MDTSevere Thunderstorm WarningCYS60 min
Jul 7, 6:08 PM MDTSevere Thunderstorm WarningCYS52 min
Jul 7, 6:13 PM MDTSevere Thunderstorm WarningCYS47 min
Jul 11, 7:22 PM MDTSevere Thunderstorm WarningCYS57 min
Jul 12, 4:17 PM MDTSevere Thunderstorm WarningCYS32 min
Jul 12, 5:02 PM MDTSevere Thunderstorm WarningCYS58 min
Jul 12, 5:56 PM MDTSevere Thunderstorm WarningCYS42 min
Jul 12, 6:10 PM MDTSevere Thunderstorm WarningCYS65 min
Jul 12, 7:13 PM MDTSevere Thunderstorm WarningCYS27 min
Aug 25, 1:41 PM MDTSevere Thunderstorm WarningCYS64 min

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.