Frost dates for Kenai Muni Airport, AK
At Kenai Muni Airport, the median last spring frost (32°F) is May 24 and the median first fall frost is Sep 12, for a typical growing season of 110 days. For a 90% chance that the last frost has passed, wait until Jun 4. Nearby ZIP codes are in USDA hardiness zones 4b to 5b.
- May 24Last spring frost (median)50% chance of 32°F after this date
- Jun 4Safer planting date10% chance of 32°F after this date
- Sep 12First fall frost (median)50% chance of 32°F by this date
- 110 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 8 | May 24 | Jun 4 |
| 28°F | Apr 22 | May 5 | May 18 |
| 24°F | Apr 8 | Apr 21 | 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 |
|---|---|---|---|
| 32°F | Aug 29 | Sep 12 | Sep 27 |
| 28°F | Sep 7 | Sep 25 | Oct 10 |
| 24°F | Sep 20 | Oct 6 | Oct 22 |
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 | 49 days | 74 days | 95 days |
| 32°F | 89 days | 110 days | 131 days |
| 28°F | 120 days | 142 days | 161 days |
| 24°F | 147 days | 168 days | 187 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 99672 | 4b | -25 to -20°F | 26 km |
| 99669 | 4b | -25 to -20°F | 27 km |
| 99610 | 4b | -25 to -20°F | 33 km |
| 99611 | 5a | -20 to -15°F | 40 km |
| 99568 | 5a | -20 to -15°F | 49 km |
| 99639 | 5b | -15 to -10°F | 68 km |
| 99682 | 5a | -20 to -15°F | 68 km |
| 99572 | 5a | -20 to -15°F | 71 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 USW00026523, at 60.5797, -151.2392, elevation 28 m (91 ft).
- Data quality: Standard (24+ years of data), 27 years of freeze data.
- Average days per year at or below 32°F: 197.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Kenai 9n (11 km)
- Soldotna 5ssw (19 km)
- Sterling 6sw (20 km)
- Kenai 29 ENE (46 km)
- Big River Lakes (63 km)
- Cooper Landing 5 W (70 km)
- Cooper Lake Project (89 km)
- Anchorage Intl Airport (93 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.