Frost Dates for 66839 — Burlington, Kansas

Half of springs at John Redmond Lake, KS see their last 32°F night by April 11; only one in ten is past it by March 27, and one in ten still has one after April 28. Planting tender crops after April 18 leaves a 30% risk of a frost on them, after April 22 20%, and after April 28 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 85% of the 110 Kansas stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 26 in half of years, as early as October 11 one year in ten, and holds off past November 9 one year in ten. A hard freeze of 28°F follows 9 days later, around November 4; in spring the one-in-ten date for 28°F is April 18, 10 days before the 32°F one. The freeze-free season lasts 199 days in a typical year, longer than at 79% of the 110 Kansas stations; it reaches 219 days one year in ten and falls short of 176 one year in ten. On average 115 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 22, and return around October 18. Severe cold of 16°F or below comes every winter, usually between December 1 and March 3.

July is the warmest month at John Redmond Lake, KS, averaging 90°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 March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 80% of years.

Warmth for growing adds up to 4,270 growing degree days a year (base 50°F), more than at 71% of the 110 Kansas stations. 36% of them (1,542) have built up by the end of June, and July adds the most, 913. Precipitation totals 37.3 inches a year, most in May (5.3") and least in January (0.9"); May to September bring 60% of it.

The nearest other station, Yates Ctr, KS, 23 miles south of Burlington, has a last frost 1 day earlier (April 10), a first frost 2 days later (October 28), a season 1 day shorter.

The first measurable snow (0.1 inch or more) in Burlington usually arrives around December 13, and the last of the season around February 13. Those are the middle dates across the winters of 1991–2020 at John Redmond Lake, KS, 3 miles away: half of years saw snow earlier, half later. Snow fell in 86% of those winters. The last 32°F night of spring typically comes 57 days after the last snow.

ZIP 66839 is 3 miles from John Redmond Lake, KS, which stands at 1,092 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 66839 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.