Frost dates for Tanana Calhoun Mem Airport, AK
At Tanana Calhoun Mem Airport, the median last spring frost (32°F) is May 29 and the median first fall frost is Aug 28, for a typical growing season of 89 days. For a 90% chance that the last frost has passed, wait until Jun 16. Nearby ZIP codes are in USDA hardiness zones 1b to 3a.
- May 29Last spring frost (median)50% chance of 32°F after this date
- Jun 16Safer planting date10% chance of 32°F after this date
- Aug 28First fall frost (median)50% chance of 32°F by this date
- 89 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 |
|---|---|---|---|
| 32°F | May 15 | May 29 | Jun 16 |
| 28°F | May 5 | May 16 | May 30 |
| 24°F | Apr 28 | May 8 | May 21 |
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 |
|---|---|---|---|
| 32°F | Aug 10 | Aug 28 | Sep 9 |
| 28°F | Aug 25 | Sep 8 | Sep 25 |
| 24°F | Sep 5 | Sep 22 | Oct 4 |
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 | 36 days | 59 days | 80 days |
| 32°F | 63 days | 89 days | 108 days |
| 28°F | 93 days | 114 days | 133 days |
| 24°F | 115 days | 135 days | 152 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 |
|---|---|---|---|
| 99777 | 1b | -55 to -50°F | 3 km |
| 99768 | 3a | -40 to -35°F | 69 km |
| 99745 | 1b | -55 to -50°F | 138 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 USW00026529, at 65.1744, -152.1069, elevation 69 m (227 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 236.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Manley Hot Springs 15ne (88 km)
- Ruby 44 ESE (121 km)
- Minchumina (142 km)
- Nenana Muni Airport (159 km)
- Kobe Hill (167 km)
- Clear Sky (173 km)
- Keystone Ridge (182 km)
- Ester (195 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.