Frost Dates for 89403 — Dayton, Nevada

Half of springs at Virginia City, NV see their last 32°F night by May 12; only one in ten is past it by April 23, and one in ten still has one after June 5. Planting tender crops after May 22 leaves a 30% risk of a frost on them, after May 30 20%, and after June 5 10%. The 24 days between the even-odds date and the one-in-ten date is wider than at 66% of the 38 Nevada 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 October 17 in half of years, as early as October 1 one year in ten, and holds off past November 6 one year in ten. A hard freeze of 28°F follows 14 days later, around October 31; in spring the one-in-ten date for 28°F is May 18, 18 days before the 32°F one. The freeze-free season lasts 155 days in a typical year, shorter than at 58% of the 38 Nevada stations; it reaches 183 days one year in ten and falls short of 127 one year in ten. On average 120 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 19 days longer, to about May 31, and return around October 7. Severe cold of 16°F or below comes in 98% of winters, usually between December 7 and February 12.

July is the warmest month at Virginia City, NV, averaging 84°F by day and 62°F at night; December is the coldest at 40°F and 26°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From July to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 68% of years and June still brings one in 17% of years.

Warmth for growing adds up to 2,606 growing degree days a year (base 50°F), fewer than at 79% of the 38 Nevada stations. 26% of them (669) have built up by the end of June, and July adds the most, 702. Precipitation totals 11.8 inches a year, most in February (2.1") and least in July (0.2"); May to September bring 17% of it.

The nearest other station, Carson City, NV, 16 miles southwest of Dayton and 1,579 feet lower, has a last frost 8 days earlier (May 4), a first frost 11 days earlier (October 6), a season 3 days shorter.

The first measurable snow (0.1 inch or more) in Dayton usually arrives around November 21, and the last of the season around April 20. Those are the middle dates across the winters of 1991–2020 at Virginia City, NV, 8.2 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 22 days after the last snow.

ZIP 89403 is 8 miles from Virginia City, NV, which stands at 6,340 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 89403 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.