Hail and Damaging Winds in Montana, July 3 to 7, 2020

Name: Hail and Damaging Winds in Montana, July 3 to 7, 2020
Start: 2020-07-03T15:40
End: 2020-07-07T16:18
Location: Montana

July 3 to 7, 2020 · NWS TFX · 29 events in 8 counties and zones

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: 29

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.

An unstable southwesterly flow aloft developed over the region on Friday July 3rd and continued through Wednesday July 8th when a Pacific trough displaced moisture and instability to the east. There were mostly sub-severe hail and winds gusts reported for a majority of days during this evening but the aforementioned trough provided adequate wind shear (30 to 55 kts), CAPE (1500 to 3500 j/kg), and moisture (td 50s and 60s) for more widespread severe weather on Tuesday July 7th. Over two dozen reports of severe hail and wind gusts were reported as storms developed over the southwest and moved northeastward into Central and North-central Montana.

The radar

The Great Falls radar (KTFX), 113 km away, was scanning. The volume nearest the first event began at 22:41 UTC.

Open the radar archive at this moment

Event by event

22 hail, 7 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Meagher

When: July 3, 3:40 PM MST
Where: Meagher County, 4 mi S of White Sulphur Spgs
Measured: 53 kt (61 mph) measured gust
Reported by: Mesonet
Coordinates: 46.492, -110.920

Mesonet station K7S6 3.6 S White Sulphur Springs reported a thunderstorm wind gust of 53 kts (61 mph).

Thunderstorm Wind, Lewis and Clark

When: July 3, 4:56 PM MST
Where: Lewis and Clark County, 13 mi S of Marysville
Measured: 56 kt (64 mph) measured gust
Reported by: Department of Highways
Coordinates: 46.542, -112.250

MDOT station at MacDonald Pass reported a 56 kt (64 mph) thunderstorm wind gust.

Hail, Judith Basin

When: July 4, 4:58 PM MST
Where: Judith Basin County, Stanford
Measured: 1 in hail
Reported by: Public
Coordinates: 47.150, -110.230

Photo of quarter size hail was sent via twitter.

Hail, Gallatin

When: July 7, 12:18 PM MST
Where: Gallatin County, 4 mi ESE of Bozeman Hot Spgs
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 45.628, -111.103

Trained spotter called in and tweeted image of quarter size hail.

Hail, Gallatin

When: July 7, 12:20 PM MST
Where: Gallatin County, 3 mi E of Gallatin Gateway
Measured: 1 in hail
Reported by: Public
Coordinates: 45.580, -111.138

Member of public relayed report of quarter size hail via mPing.

Hail, Gallatin

When: July 7, 12:25 PM MST
Where: Gallatin County, 5 mi SSW of Bozeman
Measured: 1 in hail
Reported by: Public
Coordinates: 45.613, -111.070

Member of public reported quarter size hail.

Hail, Meagher

When: July 7, 12:30 PM MST
Where: Meagher County, 1 mi NNW of Ringling
Measured: 1.5 in hail
Reported by: Post Office
Coordinates: 46.283, -110.808

Post Office reported ping pong ball size (1.5 inch diameter) hail.

Hail, Gallatin

When: July 7, 12:30 PM MST
Where: Gallatin County, 6 mi ENE of Bozeman
Measured: 1.75 in hail
Reported by: Trained Spotter
Coordinates: 45.713, -110.915

Trained spotter reported golf ball size (1.75 inch diameter) hail.

Hail, Gallatin

When: July 7, 12:30 PM MST
Where: Gallatin County, 2 mi E of Bozeman
Measured: 1 in hail
Reported by: Public
Coordinates: 45.680, -110.989

Member of public reports quarter size hail.

Hail, Chouteau

When: July 7, 12:45 PM MST
Where: Chouteau County, 10 mi SSE of Loma
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 47.796, -110.417

Trained spotter reported penny size (.75 inch diameter) and some quarter size hail (1 inch diameter) covering the ground. Some crop damage observed.

Hail, Gallatin

When: July 7, 12:50 PM MST
Where: Gallatin County, 4 mi SSE of Bozeman
Measured: 1 in hail
Reported by: CoCoRaHS
Coordinates: 45.627, -110.998

COCRAHS reported quarter size hail.

Hail, Gallatin

When: July 7, 12:57 PM MST
Where: Gallatin County, 5 mi S of Bozeman
Measured: 1.25 in hail
Reported by: Public
Coordinates: 45.608, -111.030

Member of public reported half dollar size (1.25 inch diameter) hail via mPing.

Hail, Chouteau

When: July 7, 12:59 PM MST
Where: Chouteau County, 12 mi SE of Loma
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 47.807, -110.317

Trained spotter reported quarter size hail.

Hail, Meagher

When: July 7, 1:05 PM MST
Where: Meagher County, Martinsdale
Measured: 1.5 in hail
Reported by: Public
Coordinates: 46.450, -110.320

Member of public reported ping pong ball size (1.5 inch diameter) via Facebook.

Hail, Hill

When: July 7, 1:25 PM MST
Where: Hill County, 9 mi N of Hingham
Measured: 1.75 in hail
Reported by: Public
Coordinates: 48.700, -110.420

Member of public reported golf ball size (1.75 inch diameter) hail.

Hail, Gallatin

When: July 7, 1:30 PM MST
Where: Gallatin County, 5 mi E of Gallatin Gateway
Measured: 1 in hail
Reported by: Public
Coordinates: 45.580, -111.097

Quarter size hail reported via twitter.

Hail, Gallatin

When: July 7, 1:30 PM MST
Where: Gallatin County, 5 mi E of Gallatin Gateway
Measured: 1 in hail
Reported by: Public
Coordinates: 45.580, -111.097

Member of public reported quarter size hail via twitter.

Hail, Hill

When: July 7, 1:45 PM MST
Where: Hill County, Rocky Boy
Measured: 1 in hail
Reported by: Law Enforcement
Coordinates: 48.230, -109.780

Dime (.75 inch diameter) and quarter (1 inch diameter) hail reported.

Hail, Fergus

When: July 7, 1:55 PM MST
Where: Fergus County, 3 mi SE of Denton
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 47.289, -109.875

Trained spotter reported seeing a few ping pong ball size (1.5 inch diameter) hail stones.

Hail, Fergus

When: July 7, 2:10 PM MST
Where: Fergus County, 5 mi WNW of Hilger
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 47.278, -109.448

Trained spotter reported ping pong ball (1.50 inch diameter) hail, 45 mph thunderstorm wind gusts, and just over .75 inches of rain.

Thunderstorm Wind, Fergus

When: July 7, 2:34 PM MST
Where: Fergus County, 1 mi E of Roy
Measured: 75 kt (86 mph) measured gust
Reported by: AWOS
Coordinates: 47.330, -108.909

AWOS station K1OM Oscar measured a 65 kt (75 mph) thunderstorm wind gust.

Hail, Gallatin

When: July 7, 2:40 PM MST
Where: Gallatin County, 5 mi S of Bozeman
Measured: 1 in hail
Reported by: Public
Coordinates: 45.608, -111.030

Member of public reported quarter size hail.

Thunderstorm Wind, Fergus

When: July 7, 2:41 PM MST
Where: Fergus County, 6 mi NNE of Forestgrove
Measured: 55 kt (63 mph) measured gust
Reported by: AWOS
Coordinates: 47.080, -109.031

AWOS station K1NM November measured a 55 kt (63 mph) thunderstorm wind gust.

Hail, Fergus

When: July 7, 3:00 PM MST
Where: Fergus County, Grassrange
Measured: 1.25 in hail
Reported by: Trained Spotter
Coordinates: 47.020, -108.780

Trained spotter reported four minutes of hail ranging from pea size (.25 inch diameter) to half dollar size (1.25 inch diameter).

Hail, Fergus

When: July 7, 3:00 PM MST
Where: Fergus County, 1 mi NNW of Grassrange
Measured: 1.25 in hail
Reported by: Public
Coordinates: 47.033, -108.788

Member of public relayed image of half dollar size (1.25 inch diameter) hail via twitter.

Thunderstorm Wind, Blaine

When: July 7, 3:30 PM MST
Where: Blaine County, 6 mi WSW of Hogeland
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 48.817, -108.772

Trained spotter reported downed 15 to 20 foot crab apple tree and flag pole due to thunderstorm wind gusts. Nearly an inch of rain fell.

Thunderstorm Wind, Blaine

When: July 7, 3:54 PM MST
Where: Blaine County, Turner
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 48.850, -108.400

Trained spotter reported 3 to 4 foot chunks and larger tree branches were blown down due to thunderstorm wind gusts.

Hail, Blaine

When: July 7, 4:00 PM MST
Where: Blaine County, 1 mi ESE of Turner
Measured: 1 in hail
Reported by: Public
Coordinates: 48.844, -108.380

Member of public reported quarter size hail and gusty winds.

Thunderstorm Wind, Blaine

When: July 7, 4:18 PM MST
Where: Blaine County, 13 mi S of Ft Belknap
Measured: 57 kt (66 mph) measured gust
Reported by: RAWS
Coordinates: 48.382, -108.920

RAWS station FBLM8 Fort Belknap measured a 57 kt (66 mph) thunderstorm wind gust.

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, July 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 2026-09-30. Each event’s entry at NCEI: 904227, 904228, 904232, 904252, 904253, 904254, 904255, 904256, 904258, 904261, 904263, 904264, 904265, 904266, 904267, 904250, 904268, 904269, 904270, 904271, 904272, 904273, 904274, 904275, 904276, 904277, 904279, 904280, 904281.