Frost Dates for 47909 — Lafayette, Indiana

Half of springs at Lafayette 8 S, IN see their last 32°F night by April 20; only one in ten is past it by April 6, and one in ten still has one after May 6. Planting tender crops after April 27 leaves a 30% risk of a frost on them, after May 1 20%, and after May 6 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 35% of the 125 Indiana stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 20 in half of years, as early as October 4 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 11 days later, around October 31; in spring the one-in-ten date for 28°F is April 24, 12 days before the 32°F one. The freeze-free season lasts 182 days in a typical year, longer than at 51% of the 125 Indiana stations; it reaches 201 days one year in ten and falls short of 157 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 11 days longer, to about May 1, and return around October 9. Severe cold of 16°F or below comes every winter, usually between December 1 and March 10.

July is the warmest month at Lafayette 8 S, IN, averaging 84°F by day and 64°F at night; January is the coldest at 33°F and 18°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 20% of years.

Warmth for growing adds up to 3,408 growing degree days a year (base 50°F), more than at 55% of the 125 Indiana stations. 36% of them (1,241) have built up by the end of June, and July adds the most, 741. Precipitation totals 40.1 inches a year, most in June (5.0") and least in February (2.0"); May to September bring 51% of it.

The nearest other station, Lafayette Purdue Univ Airport, IN, 5 miles northwest of Lafayette, has a last frost 6 days later (April 26), a first frost 2 days earlier (October 18), a season 9 days shorter.

The first measurable snow (0.1 inch or more) in Lafayette usually arrives around December 5, and the last of the season around March 13. Those are the middle dates across the winters of 1991–2020 at Lafayette 8 S, IN, 4.2 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 38 days after the last snow.

ZIP 47909 is 4 miles from Lafayette 8 S, IN, which stands at 732 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 47909 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.