Frost dates for Aurora, AK
At Aurora, the median last spring frost (32°F) is May 16 and the median first fall frost is Sep 6, for a typical growing season of 112 days. For a 90% chance that the last frost has passed, wait until May 29. Nearby ZIP codes are in USDA hardiness zone 2a.
- 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 6First fall frost (median)50% chance of 32°F by this date
- 112 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 14 | May 27 | Jun 8 |
| 32°F | May 5 | May 16 | May 29 |
| 28°F | Apr 26 | May 7 | May 19 |
| 24°F | Apr 16 | Apr 30 | May 11 |
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 13 | Aug 27 | Sep 8 |
| 32°F | Aug 25 | Sep 6 | Sep 20 |
| 28°F | Sep 4 | Sep 18 | Sep 30 |
| 24°F | Sep 14 | Sep 27 | Oct 8 |
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 | 72 days | 91 days | 108 days |
| 32°F | 92 days | 112 days | 130 days |
| 28°F | 115 days | 133 days | 150 days |
| 24°F | 133 days | 150 days | 167 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 |
|---|---|---|---|
| 99703 | 2a | -50 to -45°F | 5 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 USC00500490, at 64.8553, -147.7217, elevation 135 m (443 ft).
- Data quality: Representative (10+ years), 17 years of freeze data.
- Average days per year at or below 32°F: 227.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Fairbanks Midtown (4 km)
- College Obsy (6 km)
- University Exp. Station (7 km)
- Fairbanks Airport #2 (8 km)
- Goldstream Creek (8 km)
- Fairbanks Intl Airport (9 km)
- College 5 NW (11 km)
- Ester 5ne (11 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.