Montana, 2023

Winter Storm in Montana, April 1, 2023

April 1, 2023 · NWS MSO · 1 event in 1 county or zone

A low pressure system moving across the region helped develop snowfall at high elevations, including at pass level. Gusty winds also impacted the higher terrain locations.

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
1

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 MSO wrote it up.

A low pressure system moving across the region helped develop snowfall at high elevations, including at pass level. Gusty winds also impacted the higher terrain locations. The late-season nature of the event led to additional messaging considerations.

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 Missoula, MT wrote its last area forecast discussion before the first event at Mar 31, 1:19 PM MST, 15 hours 41 minutes earlier.

Area forecast discussion, Mar 31, 1:19 PM MST, 15 hours 41 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 winter storm. Local standard time, as filed.

Winter Storm, Lower Clark Fork Region

When
April 1, 5:00 AM MST to 5:30 PM MST
Where
Lower Clark Fork Region forecast zone
Reported by
Department of Highways
Coordinates
47.286, -114.685 (the zone’s center; the record gives no point)

There were two periods of impact for this storm system. During the morning and early afternoon, 06:00 MDT-15:00 MDT, snowfall rates were between 0.25 per hour and 0.50 per hour. Chains were required at Lookout Pass around 08:00 MDT. Another round of snow occurred between 16:30 MDT-18:30 MDT. Snow rates climbed to near 1 inch per hour during the evening hours. The evening snow led to chains being required at Lookout Pass around 17:45 MDT. There were also two separate vehicle accidents that led to lanes of west-bound Interstate 90 being blocked.

What these are

Winter Storm
A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

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

The same day elsewhere

More

Every storm in Montana in 2023Every state in 2023This day in weather historyWarnings in Montana, April 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: 1089284.