Last Frost Date Duluth: Frost Dates, Late Frost Risk & Growing Season
When is the last spring frost and the first autumn frost in Duluth? Frost dates from 30 years of data, the risk of late frost, frost-free days and planting dates.
The frost season in Duluth
- Last frost (average): May 5
- In 1 year out of 10 it still freezes on May 16.
- First frost: October 6
- Frost-free season: 153 days
- Frost after 15 May: in 13 % of years
Frost days per month in Duluth
- January: 30.9 · -16 °C
- February: 28 · -14 °C
- March: 28.8 · -8 °C
- April: 19.1 · -1 °C
- May: 2.4 · 5 °C
- June: 0 · 10 °C
- July: 0 · 14 °C
- August: 0 · 13 °C
- September: 0.4 · 9 °C
- October: 10.4 · 2 °C
- November: 25.7 · -5 °C
- December: 30.8 · -12 °C
- Matched to the average lows of a weather station 7 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.