Frost dates · Alaska
Alaska frost dates,
county by county.
Last spring frost and first fall frost probability data for all 30 counties in Alaska, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.
Variation across Alaska
87 days separate the earliest and latest counties.
The median last spring frost in Ketchikan Gateway Borough is March 13 — 87 days earlier than North Slope Borough at June 8. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.
Alphabetical
All Alaska counties — A to Z.
- Aleutians East Borough
- Aleutians West Census Area
- Anchorage Municipality
- Bethel Census Area
- Bristol Bay Borough
- Chugach Census Area
- Copper River Census Area
- Denali Borough
- Dillingham Census Area
- Fairbanks North Star Borough
- Haines Borough
- Hoonah-Angoon Census Area
- Juneau City and Borough
- Kenai Peninsula Borough
- Ketchikan Gateway Borough
- Kodiak Island Borough
- Kusilvak Census Area
- Lake and Peninsula Borough
- Matanuska-Susitna Borough
- Nome Census Area
- North Slope Borough
- Northwest Arctic Borough
- Petersburg Borough
- Prince of Wales-Hyder Census Area
- Sitka City and Borough
- Skagway Municipality
- Southeast Fairbanks Census Area
- Wrangell City and Borough
- Yakutat City and Borough
- Yukon-Koyukuk Census Area