Last Frost Date Bismarck: Frost Dates, Late Frost Risk & Growing Season

When is the last spring frost and the first autumn frost in Bismarck? Frost dates from 30 years of data, the risk of late frost, frost-free days and planting dates.

The frost season in Bismarck

Last frost (average): May 10
In 1 year out of 10 it still freezes on May 19.
First frost: September 28
Frost-free season: 142 days
Frost after 15 May: in 17 % of years

Frost days per month in Bismarck

January: 31 · -16 °C
February: 28.3 · -14 °C
March: 28.7 · -7 °C
April: 17.5 · -1 °C
May: 3.4 · 6 °C
June: 0 · 12 °C
July: 0 · 14 °C
August: 0 · 13 °C
September: 1.1 · 8 °C
October: 14.6 · 0 °C
November: 27.9 · -7 °C
December: 31 · -13 °C

Matched to the average lows of a weather station 5 km away – accurate to about ±1–2 weeks.
Daily minimum temperatures 2 m above ground over 30 years (1991–2020), NASA POWER; station data: Deutscher Wetterdienst (CC BY 4.0). Ground frost can form while the air at 2 m is still +2 to +3 °C.