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Frost dates for Nampa, Idaho

In a typical year, Nampa’s last spring frost lands around Apr 29 and the first fall frost around Oct 13, a growing season of about 167 days. These are odds drawn from 30-year NOAA climate normals, not a promise. USDA zone 7a.

Right now the typical frost season has arrived; planting waits for spring.

Last spring frost and first fall frost odds for Nampa, Idaho
OddsLast spring frostFirst fall frost
10 percentApr 15Sep 29
50 percentApr 29Oct 13
90 percentMay 18Oct 28

A 10 percent year is an early year, a 90 percent year a late one. Frost-sensitive planting usually waits for the 90 percent side of the last-frost band.

Soil in Nampa is typically around 50°F at 4 inches this time of year, estimated from the last two weeks of normal air temperatures.

See what is plantable in your ZIP with the what-to-plant lookup.

Common questions

When is the last frost in Nampa, Idaho?

Nampa’s last spring frost falls around April 29 in a typical year. One year in ten it is done by April 15, and one year in ten frost holds on until May 18. Frost-sensitive planting usually waits for the late side of that band.

When is the first fall frost in Nampa?

The first fall frost arrives around October 13 in a typical year, as early as September 29 in an early year and as late as October 28 in a late one.

How long is the growing season in Nampa?

About 167 days, counted between the typical last spring frost and the typical first fall frost.

What USDA zone is Nampa in?

Nampa is in USDA hardiness zone 7a under the 2023 USDA Plant Hardiness Zone Map.

Dates come from 30-year NOAA climate normals for the nearest reporting station. They describe odds, not a forecast.

Nearby cities

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