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Frost dates for Williston, North Dakota

In a typical year, Williston’s last spring frost lands around May 21 and the first fall frost around Sep 21, a growing season of about 123 days. These are odds drawn from 30-year NOAA climate normals, not a promise. USDA zone 4a.

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

Last spring frost and first fall frost odds for Williston, North Dakota
OddsLast spring frostFirst fall frost
10 percentMay 8Sep 9
50 percentMay 21Sep 21
90 percentJun 3Oct 2

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 Williston is typically around 42°F at 4 inches this time of year, estimated from the last two weeks of normal air temperatures.

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Common questions

When is the last frost in Williston, North Dakota?

Williston’s last spring frost falls around May 21 in a typical year. One year in ten it is done by May 8, and one year in ten frost holds on until June 3. Frost-sensitive planting usually waits for the late side of that band.

When is the first fall frost in Williston?

The first fall frost arrives around September 21 in a typical year, as early as September 9 in an early year and as late as October 2 in a late one.

How long is the growing season in Williston?

About 123 days, counted between the typical last spring frost and the typical first fall frost.

What USDA zone is Williston in?

Williston is in USDA hardiness zone 4a 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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