Flash Flooding and Hail in Montana, June 23, 2023

Name: Flash Flooding and Hail in Montana, June 23, 2023
Start: 2023-06-23T15:00
End: 2023-06-23T16:16
Location: Montana

June 23, 2023 · NWS BYZ · 5 events in 2 counties and zones

A very moist, easterly surface flow returned during the 3rd week of June. Dewpoints were again well above 50 degrees, with many areas around 60 degrees.

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: 5

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 BYZ wrote it up.

A very moist, easterly surface flow returned during the 3rd week of June. Dewpoints were again well above 50 degrees, with many areas around 60 degrees. In addition, atmospheric precipitable waters were well over 1.00. Winds aloft continued to be light resulting in slow-moving, heavy thunderstorms. As a result, several flash flood events occurred across portions of central and southeast Montana.

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 Jun 23, 1:28 PM MST, 1 hour 32 minutes earlier.

Area forecast discussion, Jun 23, 1:28 PM MST, 1 hour 32 minutes before

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In the hours before

Special weather statement, Jun 23, 11:50 AM MST, 3 hours 10 minutes before

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Special weather statement, Jun 23, 12:04 PM MST, 2 hours 56 minutes before

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Special weather statement, Jun 23, 1:00 PM MST, 2 hours before

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Special weather statement, Jun 23, 2:03 PM MST, 57 minutes before

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Local storm report, Jun 23, 2:54 PM MST, 6 minutes before

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The radar

The Billings radar (KBLX), 235 km away, was scanning. The volume nearest the first event began at 22:02 UTC.

Open the radar archive at this moment

Event by event

4 flash flood, 1 hail. Local standard time, as filed.

Hail, Powder River

When: June 23, 3:00 PM MST
Where: Powder River County, 11.25 mi ESE of Sayle
Measured: 1.25 in hail
Reported by: COOP Observer
Coordinates: 45.180, -105.750

Flash Flood, Stillwater

When: June 23, 3:45 PM MST
Where: Stillwater County, 2.53 mi NW of Absarokee to 1.45 mi N of Absarokee
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 45.530, -109.460

Law enforcement reported flooding in Absarokee.

Flash Flood, Stillwater

When: June 23, 3:45 PM MST
Where: Stillwater County, 6.51 mi NNW of Columbus to 4.8 mi NNW of Columbus
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 45.720, -109.290

Law enforcement reported flooding along Keyser Creek.

Flash Flood, Stillwater

When: June 23, 3:45 PM MST
Where: Stillwater County, 1.18 mi NW of Rapelje to 1.18 mi NE of Rapelje
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 45.980, -109.290

Law enforcement reported flooding near Rapelje.

Flash Flood, Powder River

When: June 23, 4:16 PM MST
Where: Powder River County, 9.03 mi NNE of Moorhead to 8.46 mi ESE of Sayle
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 45.160, -105.800

Moorhead Road was washed out at Plum Creek.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.

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

The same day elsewhere

Every storm in Montana in 2023 Every state in 2023 This day in weather history Warnings in Montana, June 2023

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: 1103205, 1103201, 1103202, 1103203, 1103204.