Frost Dates for 89049 — Tonopah, Nevada

Half of springs at Tonopah, NV see their last 32°F night by April 30; only one in ten is past it by April 13, and one in ten still has one after May 24. Planting tender crops after May 7 leaves a 30% risk of a frost on them, after May 15 20%, and after May 24 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 18 in half of years, as early as October 4 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 10 days later, around October 28; in spring the one-in-ten date for 28°F is May 8, 16 days before the 32°F one. The freeze-free season lasts 169 days in a typical year, longer than at 55% of the 38 Nevada stations; it reaches 189 days one year in ten and falls short of 146 one year in ten. On average 149 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 18 days longer, to about May 18, and return around October 8. Severe cold of 16°F or below comes every winter, usually between November 28 and February 20.

July is the warmest month at Tonopah, NV, averaging 92°F by day and 59°F at night; December is the coldest at 45°F and 20°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 44% of years.

Warmth for growing adds up to 3,159 growing degree days a year (base 50°F), fewer than at 53% of the 38 Nevada stations. 31% of them (985) have built up by the end of June, and July adds the most, 798. Precipitation totals 4.9 inches a year, most in January (0.5") and least in June (0.2"); May to September bring 43% of it.

The first measurable snow (0.1 inch or more) in Tonopah usually arrives around December 9, and the last of the season around March 16. Those are the middle dates across the winters of 1991–2020 at Smoky Valley - Carvers, NV, 35.5 miles away: half of years saw snow earlier, half later. Snow fell in 55% of those winters. The last 32°F night of spring typically comes 45 days after the last snow.

ZIP 89049 is 20 miles from Tonopah, NV, which stands at 5,395 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 89049 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.