Frost Dates for 24224 — Castlewood, Virginia

Half of springs at Nora 4 SSE, VA see their last 32°F night by April 14; only one in ten is past it by March 29, and one in ten still has one after May 5. Planting tender crops after April 22 leaves a 30% risk of a frost on them, after April 29 20%, and after May 5 10%. The 21 days between the even-odds date and the one-in-ten date is wider than at 92% of the 128 Virginia stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by November 1 in half of years, as early as October 21 one year in ten, and holds off past November 12 one year in ten. A hard freeze of 28°F follows 7 days later, around November 8; in spring the one-in-ten date for 28°F is April 20, 15 days before the 32°F one. The freeze-free season lasts 200 days in a typical year, longer than at 55% of the 128 Virginia stations; it reaches 221 days one year in ten and falls short of 177 one year in ten. On average 95 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 27, and return around October 22. Severe cold of 16°F or below comes every winter, usually between December 16 and March 1.

July is the warmest month at Nora 4 SSE, VA, averaging 80°F by day and 64°F at night; January is the coldest at 40°F and 24°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 81% of years and May still brings one in 18% of years.

Warmth for growing adds up to 3,331 growing degree days a year (base 50°F), fewer than at 75% of the 128 Virginia stations. 36% of them (1,197) have built up by the end of June, and July adds the most, 680. Precipitation totals 47.7 inches a year, most in July (5.1") and least in October (2.8"); May to September bring 47% of it.

The nearest other station, Lebanon, VA, 13 miles east of Castlewood and 746 feet lower, has a last frost 11 days later (April 25), a first frost 16 days earlier (October 16), a season 27 days shorter.

The first measurable snow (0.1 inch or more) in Castlewood usually arrives around December 8, and the last of the season around March 14. Those are the middle dates across the winters of 1991–2020 at Lebanon, VA, 13.4 miles away: half of years saw snow earlier, half later. Snow fell in 97% of those winters. The last 32°F night of spring typically comes 31 days after the last snow.

ZIP 24224 is 10 miles from Nora 4 SSE, VA, which stands at 2,658 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 24224 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.