Frost Dates for 83202 — Chubbuck, Idaho

Half of springs at Fort Hall 1 NNE, ID see their last 32°F night by May 20; only one in ten is past it by May 6, and one in ten still has one after June 12. Planting tender crops after May 31 leaves a 30% risk of a frost on them, after June 4 20%, and after June 12 10%. The 23 days between the even-odds date and the one-in-ten date is wider than at 87% of the 67 Idaho stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by September 20 in half of years, as early as September 1 one year in ten, and holds off past October 7 one year in ten. A hard freeze of 28°F follows 14 days later, around October 4; in spring the one-in-ten date for 28°F is May 23, 20 days before the 32°F one. The freeze-free season lasts 119 days in a typical year, shorter than at 81% of the 67 Idaho stations; it reaches 142 days one year in ten and falls short of 91 one year in ten. On average 186 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 21 days longer, to about June 10, and return around September 7. Severe cold of 16°F or below comes every winter, usually between November 6 and March 19.

July is the warmest month at Fort Hall 1 NNE, ID, averaging 86°F by day and 51°F at night; January is the coldest at 33°F and 15°F. A freezing night is all but certain in every month from October to May (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, June still brings one in 28% of years.

Warmth for growing adds up to 1,917 growing degree days a year (base 50°F), fewer than at 70% of the 67 Idaho stations. 26% of them (489) have built up by the end of June, and July adds the most, 573. Precipitation totals 10.5 inches a year, most in May (1.4") and least in July (0.4"); May to September bring 39% of it.

The nearest other station, Pocatello City, ID, 7 miles south of Chubbuck, has a last frost 18 days earlier (May 2), a first frost 21 days later (October 11), a season 42 days longer.

The first measurable snow (0.1 inch or more) in Chubbuck usually arrives around November 9, and the last of the season around April 13. Those are the middle dates across the winters of 1991–2020 at Fort Hall 1 NNE, ID, 5.2 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 37 days after the last snow.

ZIP 83202 is 5 miles from Fort Hall 1 NNE, ID, which stands at 4,465 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 83202 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.