Frost Dates for 22821 — Dayton, Virginia

Half of springs at Dale Enterprise, VA see their last 32°F night by April 21; only one in ten is past it by April 9, and one in ten still has one after May 7. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 2 20%, and after May 7 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 59% 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 9 one year in ten, and holds off past November 3 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 21, 16 days before the 32°F one. The freeze-free season lasts 182 days in a typical year, shorter than at 72% of the 128 Virginia stations; it reaches 200 days one year in ten and falls short of 161 one year in ten. On average 123 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 May 3, and return around October 13. Severe cold of 16°F or below comes every winter, usually between December 6 and March 2.

July is the warmest month at Dale Enterprise, VA, averaging 86°F by day and 64°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 23% of years.

Warmth for growing adds up to 3,423 growing degree days a year (base 50°F), fewer than at 71% of the 128 Virginia stations. 35% of them (1,197) have built up by the end of June, and July adds the most, 770. Precipitation totals 38.9 inches a year, most in July (4.1") and least in February (2.2"); May to September bring 50% of it.

The nearest other station, Staunton Wtp, VA, 19 miles south of Dayton and 1,189 feet lower, has a last frost 6 days earlier (April 15), a first frost 4 days later (October 27), a season 9 days longer.

The first measurable snow (0.1 inch or more) in Dayton usually arrives around December 10, and the last of the season around March 12. Those are the middle dates across the winters of 1991–2020 at Dale Enterprise, VA, 3.2 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 40 days after the last snow.

ZIP 22821 is 3 miles from Dale Enterprise, VA, which stands at 1,358 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 9 other ZIP codes share the station; its figures are presented in full for 22801 (Harrisonburg). The 2023 USDA Plant Hardiness Zone Map lists ZIP 22821 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.