Frost Dates for 24149 — Riner, Virginia

Half of springs at Christiansburg, VA see their last 32°F night by April 19; only one in ten is past it by April 3, and one in ten still has one after May 9. Planting tender crops after April 27 leaves a 30% risk of a frost on them, after May 3 20%, and after May 9 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 84% of the 128 Virginia stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 23 in half of years, as early as October 10 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 9 days later, around November 1; in spring the one-in-ten date for 28°F is April 22, 17 days before the 32°F one. The freeze-free season lasts 186 days in a typical year, shorter than at 65% of the 128 Virginia stations; it reaches 207 days one year in ten and falls short of 163 one year in ten. On average 104 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 14 days longer, to about May 3, and return around October 12. Severe cold of 16°F or below comes every winter, usually between December 13 and March 2.

July is the warmest month at Christiansburg, VA, averaging 82°F by day and 62°F at night; January is the coldest at 42°F and 23°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 24% of years.

Warmth for growing adds up to 3,054 growing degree days a year (base 50°F), fewer than at 89% of the 128 Virginia stations. 35% of them (1,081) have built up by the end of June, and July adds the most, 673. Precipitation totals 42.1 inches a year, most in May (4.7") and least in February (2.8"); May to September bring 48% of it.

The nearest other station, Floyd 2 NE, VA, 9 miles southeast of Riner and 525 feet higher, has a last frost 11 days later (April 30), a first frost 13 days earlier (October 10), a season 27 days shorter.

The first measurable snow (0.1 inch or more) in Riner usually arrives around December 9, and the last of the season around March 11. Those are the middle dates across the winters of 1991–2020 at Christiansburg, VA, 8.1 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 39 days after the last snow.

ZIP 24149 is 8 miles from Christiansburg, VA, which stands at 2,100 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 24073 (Christiansburg). The 2023 USDA Plant Hardiness Zone Map lists ZIP 24149 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.