Frost Dates for 63435 — Canton, Missouri

Half of springs at Canton L&D 20, MO see their last 32°F night by April 11; only one in ten is past it by March 29, and one in ten still has one after April 29. Planting tender crops after April 18 leaves a 30% risk of a frost on them, after April 22 20%, and after April 29 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 82% of the 158 Missouri stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 23 in half of years, as early as October 10 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 9 days later, around November 1; in spring the one-in-ten date for 28°F is April 15, 14 days before the 32°F one. The freeze-free season lasts 194 days in a typical year, shorter than at 50% of the 158 Missouri stations; it reaches 211 days one year in ten and falls short of 173 one year in ten. On average 122 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 23, and return around October 14. Severe cold of 16°F or below comes every winter, usually between December 1 and March 6.

July is the warmest month at Canton L&D 20, MO, averaging 85°F by day and 66°F at night; January is the coldest at 34°F and 17°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 83% of years.

Warmth for growing adds up to 3,503 growing degree days a year (base 50°F), fewer than at 94% of the 158 Missouri stations. 35% of them (1,243) have built up by the end of June, and July adds the most, 792. Precipitation totals 39.6 inches a year, most in May (5.2") and least in January (1.6"); May to September bring 55% of it.

The nearest other station, Keokuk Lock Dam 19, IA, 18 miles northeast of Canton, has a last frost 1 day earlier (April 10), a first frost 4 days later (October 27), a season 4 days longer.

The first measurable snow (0.1 inch or more) in Canton usually arrives around December 1, and the last of the season around March 20. Those are the middle dates across the winters of 1991–2020 at Steffenville, MO, 21.9 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 22 days after the last snow.

ZIP 63435 is 4 miles from Canton L&D 20, MO, which stands at 490 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 63435 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.