Frost Dates for 38450 — Collinwood, Tennessee

Half of springs at Waynesboro, TN see their last 32°F night by April 14; only one in ten is past it by March 28, and one in ten still has one after April 30. Planting tender crops after April 20 leaves a 30% risk of a frost on them, after April 25 20%, and after April 30 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 53% of the 144 Tennessee stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 24 in half of years, as early as October 12 one year in ten, and holds off past November 7 one year in ten. A hard freeze of 28°F follows 10 days later, around November 3; in spring the one-in-ten date for 28°F is April 19, 11 days before the 32°F one. The freeze-free season lasts 192 days in a typical year, shorter than at 77% of the 144 Tennessee stations; it reaches 213 days one year in ten and falls short of 173 one year in ten. On average 99 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 26, and return around October 15. Severe cold of 16°F or below comes in 99% of winters, usually between December 10 and February 18.

July is the warmest month at Waynesboro, TN, averaging 88°F by day and 66°F at night; January is the coldest at 49°F and 27°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 82% of years.

Warmth for growing adds up to 4,279 growing degree days a year (base 50°F), fewer than at 67% of the 144 Tennessee stations. 38% of them (1,618) have built up by the end of June, and July adds the most, 842. Precipitation totals 61.9 inches a year, most in December (6.2") and least in November (4.2"); May to September bring 41% of it.

The nearest other station, Lawrenceburg Filt Plt, TN, 24 miles east of Collinwood, has a last frost 6 days earlier (April 8), a first frost 7 days later (October 31), a season 12 days longer.

The first measurable snow (0.1 inch or more) in Collinwood usually arrives around January 17, and the last of the season around February 15. Those are the middle dates across the winters of 1991–2020 at Waynesboro, TN, 8.1 miles away: half of years saw snow earlier, half later. Snow fell in 50% of those winters. The last 32°F night of spring typically comes 58 days after the last snow.

ZIP 38450 is 8 miles from Waynesboro, TN, which stands at 750 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 38485 (Waynesboro). The 2023 USDA Plant Hardiness Zone Map lists ZIP 38450 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.