Nikolai, AK 99691 Frost Dates
99691, near Nikolai, AK: the frost window
Around 05/13 is the usual last spring frost, about 258 days away. Fall's first freeze usually shows up around 09/13, roughly 120 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Nikolai in Zone 2b (-45 to -40°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Nikolai's growing season runs out in roughly 2 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/13 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/28 and only about 1 year in 10 sees frost after that.
Nikolai against the rest of the dataset
About 120 days separate Nikolai's last and first frost, putting it 39,119 of 40,283 ZIP codes nationally. Within AK, it ranks 137 of 269.
Learn more
Two guides worth reading on 99691: local microclimates, on what one yard in Nikolai can differ from the 99691 normal, and zone vs. frost date, on why Zone 2b and Nikolai's frost date answer different questions.