Alert archive / Montana / Tornado Warnings

Tornado Warnings in Montana, 2024

8 tornado warnings in 2024. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of tornado warnings reaches back to 1986.

Tornado Warnings by county

Each county as a circle sized by its count in 2024. Tap one for its archive.

Tornado Warnings
8
Busiest month
July5 tornado warnings
Busiest day
July 13, 20245 tornado warnings

Over time

By month

Warning verification

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

3 of 8 tornado warnings covering Montana in 2024 had a tornado report inside them; 3 of 3 tornado reports fell inside a warning, on average 23 minutes after it went out.

Montana, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings8363%3100%23 min

Each office's whole area, 2024

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Billings, MT: tornado warnings10100%0
NWS Glasgow, MT: tornado warnings7357%3100%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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeCountiesLasted
Jun 15, 7:22 PM MDTTornado Warning Tornado observedGGWDaniels, McCone, Richland, Roosevelt, Sheridan38 min
Jun 27, 3:34 PM MDTTornado WarningBYZRosebud26 min
Jul 12, 6:47 PM MDTTornado WarningGGWDaniels, Valley28 min
Jul 12, 7:05 PM MDTTornado Warning Tornado observedGGWDaniels, Valley25 min
Jul 12, 7:21 PM MDTTornado Warning Tornado observedGGWDaniels, Valley24 min
Jul 12, 7:47 PM MDTTornado Warning Tornado observedGGWDaniels, Roosevelt, Valley28 min
Jul 13, 4:31 PM MDTTornado WarningGGWPhillips31 min
Sep 17, 5:41 PM MDTTornado WarningGGWDaniels, Roosevelt34 min

By county

Every county with at least one alert. A county page lists each alert that covered it.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20232025

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.