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Frost dates for Twin Falls, Idaho

In a typical year, Twin Falls’s last spring frost lands around Apr 30 and the first fall frost around Oct 9, a growing season of about 162 days. These are odds drawn from 30-year NOAA climate normals, not a promise. USDA zone 6b.

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

Last spring frost and first fall frost odds for Twin Falls, Idaho
OddsLast spring frostFirst fall frost
10 percentApr 17Sep 24
50 percentApr 30Oct 9
90 percentMay 14Oct 24

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 Twin Falls 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 Twin Falls, Idaho?

Twin Falls’s last spring frost falls around April 30 in a typical year. One year in ten it is done by April 17, and one year in ten frost holds on until May 14. Frost-sensitive planting usually waits for the late side of that band.

When is the first fall frost in Twin Falls?

The first fall frost arrives around October 9 in a typical year, as early as September 24 in an early year and as late as October 24 in a late one.

How long is the growing season in Twin Falls?

About 162 days, counted between the typical last spring frost and the typical first fall frost.

What USDA zone is Twin Falls in?

Twin Falls is in USDA hardiness zone 6b 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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