Frost dates for Baker Muni Airport, MT
At Baker Muni Airport, the median last spring frost (32°F) is May 16 and the median first fall frost is Sep 26, for a typical growing season of 132 days. For a 90% chance that the last frost has passed, wait until May 29. Nearby ZIP codes are in USDA hardiness zones 4a to 4b.
- May 16Last spring frost (median)50% chance of 32°F after this date
- May 29Safer planting date10% chance of 32°F after this date
- Sep 26First fall frost (median)50% chance of 32°F by this date
- 132 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | May 15 | May 27 | Jun 10 |
| 32°F | May 4 | May 16 | May 29 |
| 28°F | Apr 20 | May 4 | May 19 |
| 24°F | Apr 8 | Apr 24 | May 8 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 1 | Sep 16 | Sep 29 |
| 32°F | Sep 11 | Sep 26 | Oct 7 |
| 28°F | Sep 20 | Oct 4 | Oct 17 |
| 24°F | Sep 27 | Oct 13 | Oct 26 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 91 days | 110 days | 129 days |
| 32°F | 111 days | 132 days | 149 days |
| 28°F | 131 days | 150 days | 170 days |
| 24°F | 150 days | 170 days | 191 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 59313 | 4b | -25 to -20°F | 11 km |
| 58643 | 4a | -30 to -25°F | 27 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USW00094055, at 46.3583, -104.2500, elevation 906 m (2,971 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 187.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Baker (3 km)
- Plevna (21 km)
- Carlyle 13 NW (43 km)
- Ekalaka (57 km)
- Wibaux 2 E (70 km)
- Mildred 5 N (71 km)
- Mizpah 4 NNW (80 km)
- Powderville 8 NNE (83 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.