Frost Dates for 52544 — Centerville, Iowa

Half of springs at Centerville, IA see their last 32°F night by April 28; only one in ten is past it by April 13, and one in ten still has one after May 11. Planting tender crops after May 3 leaves a 30% risk of a frost on them, after May 6 20%, and after May 11 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 42% of the 132 Iowa stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 14 in half of years, as early as September 26 one year in ten, and holds off past October 26 one year in ten. A hard freeze of 28°F follows 10 days later, around October 24; in spring the one-in-ten date for 28°F is May 2, 9 days before the 32°F one. The freeze-free season lasts 168 days in a typical year, longer than at 62% of the 132 Iowa stations; it reaches 186 days one year in ten and falls short of 147 one year in ten. On average 132 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 9 days longer, to about May 7, and return around October 3. Severe cold of 16°F or below comes every winter, usually between November 18 and March 18.

July is the warmest month at Centerville, IA, averaging 86°F by day and 63°F at night; January is the coldest at 33°F and 12°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 40% of years.

Warmth for growing adds up to 3,175 growing degree days a year (base 50°F), more than at 70% of the 132 Iowa stations. 34% of them (1,095) have built up by the end of June, and July adds the most, 758. Precipitation totals 36.3 inches a year, most in May (5.2") and least in January (1.0"); May to September bring 58% of it.

The nearest other station, Unionville, MO, 19 miles south of Centerville and 155 feet higher, has a last frost 11 days earlier (April 17), a first frost 8 days later (October 22), a season 18 days longer.

The first measurable snow (0.1 inch or more) in Centerville usually arrives around November 29, and the last of the season around March 10. Those are the middle dates across the winters of 1991–2020 at Centerville, IA, 0.2 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 49 days after the last snow.

ZIP 52544 is under a mile from Centerville, IA, which stands at 905 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 52544 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.