Frost dates for Annette Island Airport, AK
At Annette Island Airport, the median last spring frost (32°F) is Apr 4 and the median first fall frost is Oct 31, for a typical growing season of 208 days. For a 90% chance that the last frost has passed, wait until Apr 22. Nearby ZIP codes are in USDA hardiness zones 7b to 8a.
- Apr 4Last spring frost (median)50% chance of 32°F after this date
- Apr 22Safer planting date10% chance of 32°F after this date
- Oct 31First fall frost (median)50% chance of 32°F by this date
- 208 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 | Apr 10 | Apr 27 | May 10 |
| 32°F | Mar 20 | Apr 4 | Apr 22 |
| 28°F | Feb 26 | Mar 16 | Mar 31 |
| 24°F | Jan 20 | Feb 28 | Mar 18 |
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 | Oct 2 | Oct 16 | Oct 30 |
| 32°F | Oct 15 | Oct 31 | Nov 20 |
| 28°F | Oct 30 | Nov 18 | Dec 9 |
| 24°F | Nov 12 | Dec 2 | Jan 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 | 152 days | 171 days | 193 days |
| 32°F | 185 days | 208 days | 232 days |
| 28°F | 218 days | 246 days | 277 days |
| 24°F | 250 days | 286 days | 325 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 99% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 99926 | 8a | 10 to 15°F | 13 km |
| 99901 | 7b | 5 to 10°F | 71 km |
| 99903 | 7b | 5 to 10°F | 84 km |
| 99921 | 7b | 5 to 10°F | 89 km |
| 99919 | 7b | 5 to 10°F | 89 km |
| 99922 | 8a | 10 to 15°F | 98 km |
| 99925 | 7b | 5 to 10°F | 104 km |
| 99918 | 8a | 10 to 15°F | 120 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 USW00025308, at 55.0389, -131.5786, elevation 33 m (109 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 68.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Metlakatla 6 S (1 km)
- Beaver Falls (36 km)
- Ketchikan Intl Airport (36 km)
- Ketchikan 10n (48 km)
- Thorne Bay (94 km)
- Craig (110 km)
- Klawock Airport (112 km)
- Hyder (138 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.