Frost dates for Lindbergh Lake, MT
At Lindbergh Lake, the median last spring frost (32°F) is May 20 and the median first fall frost is Sep 22, for a typical growing season of 120 days. For a 90% chance that the last frost has passed, wait until Jun 7. Nearby ZIP codes are in USDA hardiness zone 5a.
- May 20Last spring frost (median)50% chance of 32°F after this date
- Jun 7Safer planting date10% chance of 32°F after this date
- Sep 22First fall frost (median)50% chance of 32°F by this date
- 120 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 26 | Jun 11 | Jun 28 |
| 32°F | May 7 | May 20 | Jun 7 |
| 28°F | Apr 20 | May 3 | May 17 |
| 24°F | Apr 3 | Apr 19 | May 3 |
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 | Aug 23 | Sep 8 | Sep 22 |
| 32°F | Sep 5 | Sep 22 | Oct 5 |
| 28°F | Sep 19 | Oct 4 | Oct 18 |
| 24°F | Sep 30 | Oct 16 | Nov 1 |
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 | 65 days | 88 days | 109 days |
| 32°F | 97 days | 120 days | 141 days |
| 28°F | 132 days | 152 days | 172 days |
| 24°F | 157 days | 181 days | 203 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 |
|---|---|---|---|
| 59826 | 5a | -20 to -15°F | 6 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 USC00245043, at 47.4083, -113.7125, elevation 1317 m (4,320 ft).
- Data quality: Standard (24+ years of data), 28 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
- Seeley Lake Ranger Station (26 km)
- Saint Ignatius (31 km)
- Polson (47 km)
- Skq Dam (50 km)
- Swan Lake (57 km)
- Bigfork 13 S (57 km)
- Missoula 2 NE (60 km)
- Potomac (60 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.