Frost dates in Clark County, Idaho

Pine forest above the Sawtooth Valley with the Sawtooth Mountains behind, Idaho — Photo: Acroterion, CC BY-SA 4.0, via Wikimedia Commons

The average last spring frost in Clark County falls May 18 and the average first fall frost Sep 30, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 5b. Places: Dubois, Spencer. Pick a ZIP for 10% and 90% odds, soil temperature and the 7-day freeze forecast.

ZIP	Place	Last spring frost	First fall frost	Zone
83423	Dubois	May 18	Sep 30	5b
83446	Spencer	May 18	Sep 30	5b

Nearby counties

Jefferson County Fremont County Madison County Teton County Butte County Bonneville County

All Idaho counties · Download Idaho frost dates (CSV)

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