Tanana, AK 99777 Frost Dates
Frost dates for Tanana, AK, ZIP 99777
Around 05/29 is the usual last spring frost, about 274 days away. The first fall frost typically arrives around 08/28, about 89 frost-free days later.
Tanana sits in USDA Zone 1b (-55 to -50°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 1b around Tanana has about any day now left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 05/29 isn't a guarantee
05/29 is the middle of 30 years of NOAA records, not a promise. Plant by 05/15 and you're betting against frost in roughly 9 years out of 10. 06/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Tanana compares
About 89 days separate Tanana's last and first frost, putting it 39,934 of 40,283 ZIP codes nationally. Within AK, it ranks 220 of 269.
Learn more
local microclimates explains what one yard in Tanana can differ from the 99777 normal, and zone vs. frost date explains why Zone 1b and Tanana's frost date answer different questions.