Montana, 2001

Flash Flood and Hail in Montana, July 12, 2001

July 12, 2001 · NWS BYZ · 7 events in 4 counties and zones

5 hail, 1 flash flood, 1 thunderstorm wind, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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
7

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 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 Billings, MT wrote its last area forecast discussion before the first event at Jul 12, 12:50 PM MST, 4 hours 40 minutes earlier.

Area forecast discussion, Jul 12, 12:50 PM MST, 4 hours 40 minutes before
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The radar

The Billings radar (KBLX), 155 km away, was scanning. The volume nearest the first event began at 01:58 UTC.

Open the radar archive at this moment

Event by event

5 hail, 1 flash flood, 1 thunderstorm wind. Local standard time, as filed.

Flash Flood, Park

When
July 12, 5:30 PM MST
Where
Park County, Livingston
Reported by
TRAINED SPOTTER
Coordinates
45.488, -110.526 (the zone’s center; the record gives no point)

Four feet of water in the B Street underpass. Several streets with 6 inches of water flowing like a river.

Hail, Carter

When
July 12, 6:58 PM MST
Where
Carter County, 18 mi NW of Alzada
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.200, -104.683

Hail, Golden Valley

When
July 12, 7:15 PM MST
Where
Golden Valley County, 15 mi N of Lavina
Measured
1.25 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.500, -108.933

Hail, Golden Valley

When
July 12, 8:15 PM MST
Where
Golden Valley County, 7 mi N of Lavina
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.383, -108.933

Hail, Musselshell

When
July 12, 8:25 PM MST
Where
Musselshell County, 12 mi W of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.450, -108.783

Hail, Musselshell

When
July 12, 8:32 PM MST
Where
Musselshell County, 7 mi W of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.450, -108.683

Thunderstorm Wind, Musselshell

When
July 12, 8:38 PM MST
Where
Musselshell County, Roundup
Measured
60 kt (69 mph)
Reported by
TRAINED SPOTTER
Coordinates
46.450, -108.533

What these are

Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.

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

The same day elsewhere

More

Every storm in Montana in 2001Every state in 2001This day in weather historyWarnings in Montana, July 2001

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 2026-10-01. Each event’s entry at NCEI: 5259115, 5259109, 5259110, 5259111, 5259114, 5259112, 5259113.