Heavy Snow in Idaho, February 17 to 19, 2018

Name: Heavy Snow in Idaho, February 17 to 19, 2018
Start: 2018-02-17T14:00
End: 2018-02-19T00:00
Location: Idaho

February 17 to 19, 2018 · NWS MSO · 1 event in 1 county or zone

Heavy snow fell across north-central Idaho the afternoon of the 17th ahead of a warm front, then continued on the 18th along an Arctic front.

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.

Heavy snow fell across north-central Idaho the afternoon of the 17th ahead of a warm front, then continued on the 18th along an Arctic 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 Missoula, MT wrote its last area forecast discussion before the first event at Feb 17, 1:26 PM PST, 34 minutes earlier.

Area forecast discussion, Feb 17, 1:26 PM PST, 34 minutes before

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In the hours before

Local storm report, Feb 17, 10:40 AM PST, 3 hours 20 minutes before

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Local storm report, Feb 17, 12:16 PM PST, 1 hour 44 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 heavy snow. Local standard time, as filed.

Heavy Snow, Southern Clearwater Mountains

When: February 17, 2:00 PM PST to February 19, 12:00 AM PST
Where: Southern Clearwater Mountains forecast zone
Reported by: Department of Highways
Coordinates: 45.844, -115.467 (the zone’s center; the record gives no point)

Heavy bursts of snow with amounts around 12 inches were common leading to difficult travel over area mountain passes. The highway department noted that it was difficult to keep up with snow rates near Lolo Pass late on the 17th. Also, 24 inches of snow fell at Powell from the 16th through the 18th.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.

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

The same day elsewhere

Every storm in Idaho in 2018 Every state in 2018 This day in weather history Warnings in Idaho, February 2018

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: 733102.