Frost Dates for 67576 — St John, Kansas

Half of springs at Hudson, KS see their last 32°F night by April 18; only one in ten is past it by April 3, and one in ten still has one after May 2. Planting tender crops after April 24 leaves a 30% risk of a frost on them, after April 28 20%, and after May 2 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 44% of the 110 Kansas stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 21 in half of years, as early as October 5 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 9 days later, around October 30; in spring the one-in-ten date for 28°F is April 22, 10 days before the 32°F one. The freeze-free season lasts 185 days in a typical year, shorter than at 58% of the 110 Kansas stations; it reaches 204 days one year in ten and falls short of 165 one year in ten. On average 113 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 11 days longer, to about April 29, and return around October 13. Severe cold of 16°F or below comes every winter, usually between November 27 and March 7.

July is the warmest month at Hudson, KS, averaging 94°F by day and 68°F at night; January is the coldest at 44°F and 21°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 13% of years.

Warmth for growing adds up to 4,366 growing degree days a year (base 50°F), more than at 80% of the 110 Kansas stations. 36% of them (1,571) have built up by the end of June, and July adds the most, 950. Precipitation totals 28.9 inches a year, most in May (4.6") and least in January (0.8"); May to September bring 62% of it.

The nearest other station, Larned, KS, 20 miles northwest of St John, has a last frost 2 days earlier (April 16), a first frost 6 days later (October 27), a season 5 days longer.

The first measurable snow (0.1 inch or more) in St John usually arrives around December 5, and the last of the season around March 10. Those are the middle dates across the winters of 1991–2020 at Hudson, KS, 9.7 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 39 days after the last snow.

ZIP 67576 is 10 miles from Hudson, KS, which stands at 1,867 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 67576 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.