Kotlik, AK 99620 Frost Dates
Frost dates for Kotlik, AK, ZIP 99620
Around 06/05 is the usual last spring frost, about 281 days away. The first fall frost typically arrives around 09/03, about 88 frost-free days later.
The USDA Plant Hardiness Zone Map puts Kotlik in Zone 4a (-30 to -25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 4a around Kotlik has about 1 week 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 06/05 isn't a guarantee
06/05 is the middle of 30 years of NOAA records, not a promise. Plant by 05/20 and you're betting against frost in roughly 9 years out of 10. 06/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Kotlik compares
Kotlik's growing season runs about 88 days, ranking 39,952 of 40,283 US ZIP codes measured here, longest to shortest. Within AK, it ranks 228 of 269.
Learn more
the frost range explains how to read the range around Kotlik's dates instead of trusting one, and local microclimates explains what one yard in Kotlik can differ from the 99620 normal.