Hail and Damaging Winds in Montana, June 24, 2020

Name: Hail and Damaging Winds in Montana, June 24, 2020
Start: 2020-06-24T16:55
End: 2020-06-24T19:37
Location: Montana

June 24, 2020 · NWS TFX · 11 events in 4 counties and zones

Thunderstorms develop across western and southwest Montana, and continue to become more widespread. Daytime heating provides moderate instability for convective initiation.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 11

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS TFX wrote it up.

Thunderstorms develop across western and southwest Montana, and continue to become more widespread. Daytime heating provides moderate instability for convective initiation. Inverted-v type soundings, characterized by a deep and dry boundary layer, support DCAPE values near 1000 J/kg. Thus, damaging wind gusts are the primary hazard associated with stronger thunderstorms. Shear profiles strengthen and may be enough to support a few supercell thunderstorms capable of producing locally heavy |rain, small hail, and with marginal support for an isolated larger hail event to the size of quarters. The severe storm potential peaks by early evening, although showers and thunderstorms continue to spread across the region overnight. This activity is associated with a passing upper level shortwave trough and its associated surface front.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before the first event at Jun 24, 2:09 PM MST, 2 hours 46 minutes earlier.

Area forecast discussion, Jun 24, 2:09 PM MST, 2 hours 46 minutes before

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In the hours before

Special weather statement, Jun 24, 3:16 PM MST, 1 hour 39 minutes before

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Special weather statement, Jun 24, 4:05 PM MST, 50 minutes before

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Special weather statement, Jun 24, 4:17 PM MST, 38 minutes before

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Special weather statement, Jun 24, 4:37 PM MST, 18 minutes before

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Special weather statement, Jun 24, 4:41 PM MST, 14 minutes before

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Special weather statement, Jun 24, 4:44 PM MST, 11 minutes before

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The radar

The Missoula radar (KMSX), 212 km away, was scanning. The volume nearest the first event began at 23:53 UTC.

Open the radar archive at this moment

Event by event

10 thunderstorm wind, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Madison

When: June 24, 4:55 PM MST
Where: Madison County, Twin Bridges Arpt
Measured: 64 kt (74 mph) measured gust
Reported by: AWOS
Coordinates: 45.530, -112.300

Data from awos station K7S1 Twin Bridges.

Thunderstorm Wind, Lewis and Clark

When: June 24, 4:58 PM MST
Where: Lewis and Clark County, 3.51 mi SE of Sieben
Measured: 51 kt (59 mph) measured gust
Reported by: Mesonet
Coordinates: 46.890, -112.110

Report from 8 SSW Wolf Creek. Mesonet station 301005 Sieben.

Thunderstorm Wind, Madison

When: June 24, 5:50 PM MST
Where: Madison County, 3.59 mi SSW of Ennis
Measured: 54 kt (62 mph) measured gust
Reported by: Mesonet
Coordinates: 45.300, -111.750

Mesonet station ENNM8 Ennis raws. Time estimated based on radar.

Thunderstorm Wind, Teton

When: June 24, 6:04 PM MST
Where: Teton County, 2.27 mi SSW of Cleiv
Measured: 50 kt (58 mph) measured gust
Reported by: Public
Coordinates: 47.670, -111.900

Public report.

Hail, Teton

When: June 24, 6:36 PM MST
Where: Teton County, 11.04 mi ENE of Power
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 47.760, -111.450

A lot of quarter to ping pong sized hail. Also, reports wind shredded pine trees and a lot of branches down.

Thunderstorm Wind, Chouteau

When: June 24, 6:54 PM MST
Where: Chouteau County, 9.75 mi WNW of Floweree
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 47.790, -111.220

Corrected time. Reports strong winds brought rain into attic of house and knocked down trees. Also, reports a pile of peas sized hail. Wind speed and gust estimate not reported.

Thunderstorm Wind, Chouteau

When: June 24, 7:00 PM MST
Where: Chouteau County, 0.46 mi W of Carter
Measured: 52 kt (60 mph) measured gust
Reported by: Trained Spotter
Coordinates: 47.780, -110.960

Trained spotter reports estimated wind gusts near 60 mph in Carter.

Thunderstorm Wind, Chouteau

When: June 24, 7:06 PM MST
Where: Chouteau County, 6.71 mi NW of Floweree
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 47.800, -111.130

Relayed report from trained spotter of trees stripped and power outage from thunderstorm winds gusts. Wind speed and gust estimate not reported.

Thunderstorm Wind, Chouteau

When: June 24, 7:06 PM MST
Where: Chouteau County, 4.16 mi NW of Floweree
Measured: 56 kt (64 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 47.780, -111.080

Wind and rain reduced visibility to less than 100 feet. Reports 0.80 inches of rain in 15 minutes. Also, reports pea sized hail.

Thunderstorm Wind, Chouteau

When: June 24, 7:12 PM MST
Where: Chouteau County, 0.46 mi W of Carter
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 47.780, -110.960

Reports some tree branch damage from strong winds. Small hail also observed along with some water on road. Wind speed and gust estimate not reported.

Thunderstorm Wind, Chouteau

When: June 24, 7:37 PM MST
Where: Chouteau County, 9.75 mi WNW of Floweree
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 47.790, -111.220

Reports strong winds brought rain into attic of house and knocked down trees. Also, reports a pile of pea sized hail. Wind speed and gust estimate not reported.

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2020 Every state in 2020 This day in weather history Warnings in Montana, June 2020

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 906290, 906291, 906293, 906294, 906284, 906286, 906295, 906287, 906296, 906288, 906289.