Frost Dates for 99652 — Big Lake, Alaska

Half of springs at Whites Crossing, AK see their last 32°F night by May 29; only one in ten is past it by May 13, and one in ten still has one after June 9. Planting tender crops after June 2 leaves a 30% risk of a frost on them, after June 5 20%, and after June 9 10%. The 11 days between the even-odds date and the one-in-ten date is narrower than at 84% of the 37 Alaska stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 7 in half of years, as early as August 24 one year in ten, and holds off past September 21 one year in ten. A hard freeze of 28°F follows 12 days later, around September 19; in spring the one-in-ten date for 28°F is May 27, 13 days before the 32°F one. The freeze-free season lasts 100 days in a typical year, shorter than at 95% of the 37 Alaska stations; it reaches 122 days one year in ten and falls short of 80 one year in ten. On average 228 nights a year drop to 32°F or below. Severe cold of 16°F or below comes every winter, usually between October 16 and April 11.

July is the warmest month at Whites Crossing, AK, averaging 71°F by day and 49°F at night; January is the coldest at 16°F and -2°F. A freezing night is all but certain in every month from September to May (a 90% chance or more). July is the only month with under a 10% chance of a 32°F night. In spring, June still brings one in 37% of years.

Warmth for growing adds up to 794 growing degree days a year (base 50°F), more than at 68% of the 37 Alaska stations. 30% of them (238) have built up by the end of June, and July adds the most, 316.

The nearest other station, Willow West, AK, 14 miles north of Big Lake, has a last frost 14 days earlier (May 15), a first frost 11 days later (September 18), a season 26 days longer.

The first measurable snow (0.1 inch or more) in Big Lake usually arrives around October 23, and the last of the season around March 31. Those are the middle dates across the winters of 1991–2020 at Whites Crossing, AK, 11 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 59 days after the last snow.

ZIP 99652 is 11 miles from Whites Crossing, AK, which stands at 270 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 99652 in zone 4a, the band where the coldest night of the year averaged -30 to -25°F (-34.4 to -31.7°C) over 1991–2020; a zone describes winter lows, not frost dates.