Frost Dates for 29817 — Blackville, South Carolina

Half of springs at Blackville 3 W, SC see their last 32°F night by March 20; only one in ten is past it by February 27, and one in ten still has one after April 8. Planting tender crops after March 28 leaves a 30% risk of a frost on them, after April 2 20%, and after April 8 10%. The 19 days between the even-odds date and the one-in-ten date is wider than at 86% of the 105 South Carolina stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 13 in half of years, as early as October 29 one year in ten, and holds off past December 2 one year in ten. A hard freeze of 28°F follows 17 days later, around November 30; in spring the one-in-ten date for 28°F is March 26, 13 days before the 32°F one. The freeze-free season lasts 238 days in a typical year, longer than at 67% of the 105 South Carolina stations; it reaches 266 days one year in ten and falls short of 212 one year in ten. On average 39 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 13 days longer, to about April 2, and return around November 2. Nights of 24°F, cold enough to damage hardier plants, come in 96% of winters and 16°F in 39%.

July is the warmest month at Blackville 3 W, SC, averaging 91°F by day and 71°F at night; January is the coldest at 57°F and 36°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 85% of years and April still brings one in 24% of years.

Warmth for growing adds up to 5,629 growing degree days a year (base 50°F), more than at 69% of the 105 South Carolina stations. 41% of them (2,303) have built up by the end of June, and July adds the most, 950. Precipitation totals 46.2 inches a year, most in June (5.3") and least in November (2.5"); May to September bring 49% of it.

The nearest other station, Barnwell 5 ENE, SC, 8 miles south of Blackville, has a last frost 2 days later (March 22), a first frost 4 days earlier (November 9), a season 5 days shorter.

Measurable snow is rare here: only 6 of 24 winters from 1991 to 2020 recorded 0.1 inch or more at Bamberg, SC, 15.4 miles away, so there is no typical first-snow date to plan around.

ZIP 29817 is 3 miles from Blackville 3 W, SC, which stands at 317 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 29853 (Williston). The 2023 USDA Plant Hardiness Zone Map lists ZIP 29817 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.