Frost Dates for 66619 — Topeka, Kansas

Half of springs at Topeka Forbes Field, KS see their last 32°F night by April 15; only one in ten is past it by April 2, and one in ten still has one after April 30. Planting tender crops after April 21 leaves a 30% risk of a frost on them, after April 25 20%, and after April 30 10%. The 15 days between the even-odds date and the one-in-ten date is wider than at 57% 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 10 days later, around October 31; in spring the one-in-ten date for 28°F is April 21, 9 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 164 one year in ten. On average 117 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 12 days longer, to about April 27, and return around October 11. Severe cold of 16°F or below comes every winter, usually between November 28 and March 5.

July is the warmest month at Topeka Forbes Field, KS, averaging 91°F by day and 69°F at night; January is the coldest at 41°F and 19°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 10% of years.

Warmth for growing adds up to 4,183 growing degree days a year (base 50°F), more than at 61% of the 110 Kansas stations. 36% of them (1,523) have built up by the end of June, and July adds the most, 916. Precipitation totals 36.7 inches a year, most in May (5.2") and least in January (0.8"); May to September bring 61% of it.

The nearest other station, Topeka - NWS, KS, 9 miles north of Topeka and 187 feet lower, has a last frost 1 day later (April 16), a first frost 1 day later (October 22), a season 4 days longer.

The first measurable snow (0.1 inch or more) in Topeka usually arrives around December 10, and the last of the season around March 2. Those are the middle dates across the winters of 1991–2020 at Auburn, KS, 7 miles away: half of years saw snow earlier, half later. Snow fell in 95% of those winters. The last 32°F night of spring typically comes 44 days after the last snow.

ZIP 66619 is 2 miles from Topeka Forbes Field, KS, which stands at 1,067 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 66614 (Topeka). The 2023 USDA Plant Hardiness Zone Map lists ZIP 66619 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.