Heavy Snow in Idaho, November 17 to 19, 2011

Name: Heavy Snow in Idaho, November 17 to 19, 2011
Start: 2011-11-17T20:30
End: 2011-11-19T02:30
Location: Idaho

November 17 to 19, 2011 · NWS OTX · 3 events in 3 counties and zones

A deep closed low pressure system moved into southwestern Washington. Bands of snow developed along a TROWAL (TROugh of Warm Air ALoft) that extended from northern Idaho into eastern Washington.

Where it happened

Every event with a place to put it; 3 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: 3

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 OTX wrote it up.

A deep closed low pressure system moved into southwestern Washington. Bands of snow developed along a TROWAL (TROugh of Warm Air ALoft) that extended from northern Idaho into eastern Washington. This feature was nearly stationary overnight on November 17th through November 18th. Snow showers persisted into the early hours of November 19th before this feature weakened and shifted eastward. Heavier snowfall reports were up to around six inches in the valleys to up to a foot in the Central Panhandle Mountains.

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 Spokane, WA wrote its last area forecast discussion before the first event at Nov 17, 3:48 PM PST, 4 hours 42 minutes earlier.

Area forecast discussion, Nov 17, 3:48 PM PST, 4 hours 42 minutes before

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Hazardous weather outlook, Nov 17, 6:09 AM PST, 14 hours 21 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

3 heavy snow. Local standard time, as filed.

Heavy Snow, Coeur D'Alene Area

When: November 17, 8:30 PM PST to November 18, 11:00 PM PST
Where: Coeur D'Alene Area forecast zone
Reported by: Trained Spotter
Coordinates: 47.675, -116.700 (the zone’s center; the record gives no point)

Heavy Snow, Northern Panhandle

When: November 17, 10:00 PM PST to November 18, 6:00 PM PST
Where: Northern Panhandle forecast zone
Reported by: Trained Spotter
Coordinates: 48.247, -116.588 (the zone’s center; the record gives no point)

Heavy Snow, Central Panhandle Mountains

When: November 17, 10:00 PM PST to November 19, 2:30 AM PST
Where: Central Panhandle Mountains forecast zone
Reported by: COOP Observer
Coordinates: 47.265, -116.491 (the zone’s center; the record gives no point)

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 2011 Every state in 2011 This day in weather history Warnings in Idaho, November 2011

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: 351146, 351145, 351148.