Frost Dates for 83837 — Kellogg, Idaho

Half of springs at Kellogg, ID see their last 32°F night by May 14; only one in ten is past it by April 30, and one in ten still has one after June 3. Planting tender crops after May 21 leaves a 30% risk of a frost on them, after May 26 20%, and after June 3 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 69% of the 67 Idaho stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 26 in half of years, as early as September 9 one year in ten, and holds off past October 9 one year in ten. A hard freeze of 28°F follows 12 days later, around October 8; in spring the one-in-ten date for 28°F is May 13, 21 days before the 32°F one. The freeze-free season lasts 131 days in a typical year, shorter than at 67% of the 67 Idaho stations; it reaches 152 days one year in ten and falls short of 106 one year in ten. On average 147 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 19 days longer, to about June 2, and return around September 10. Severe cold of 16°F or below comes every winter, usually between November 23 and March 2.

July is the warmest month at Kellogg, ID, averaging 85°F by day and 51°F at night; December is the coldest at 36°F and 22°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 87% of years and June still brings one in 13% of years.

Warmth for growing adds up to 1,843 growing degree days a year (base 50°F), fewer than at 76% of the 67 Idaho stations. 28% of them (515) have built up by the end of June, and July adds the most, 549. Precipitation totals 34.1 inches a year, most in November (4.6") and least in August (0.8"); May to September bring 26% of it.

The nearest other station, Wallace, ID, 10 miles southeast of Kellogg and 333 feet higher, has a last frost 9 days earlier (May 5), a first frost 6 days later (October 2), a season 18 days longer.

The first measurable snow (0.1 inch or more) in Kellogg usually arrives around November 22, and the last of the season around March 24. Those are the middle dates across the winters of 1991–2020 at Kellogg, ID, 0.6 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 51 days after the last snow.

ZIP 83837 is under a mile from Kellogg, ID, which stands at 2,377 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 83837 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.