Frost Dates for 89431 — Sparks, Nevada

Half of springs at Sparks, NV see their last 32°F night by May 1; only one in ten is past it by April 17, and one in ten still has one after May 25. Planting tender crops after May 8 leaves a 30% risk of a frost on them, after May 14 20%, and after May 25 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 10 in half of years, as early as September 29 one year in ten, and holds off past October 24 one year in ten. A hard freeze of 28°F follows 13 days later, around October 23; in spring the one-in-ten date for 28°F is May 2, 23 days before the 32°F one. The freeze-free season lasts 160 days in a typical year, longer than at 50% of the 38 Nevada stations; it reaches 178 days one year in ten and falls short of 135 one year in ten. On average 141 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 22 days longer, to about May 23, and return around October 1. Severe cold of 16°F or below comes every winter, usually between November 29 and February 8.

July is the warmest month at Sparks, NV, averaging 92°F by day and 55°F at night; December is the coldest at 47°F and 25°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 51% of years.

Warmth for growing adds up to 2,956 growing degree days a year (base 50°F), fewer than at 61% of the 38 Nevada stations. 31% of them (904) have built up by the end of June, and July adds the most, 736. Precipitation totals 8.4 inches a year, most in January (1.3") and least in September (0.2"); May to September bring 24% of it.

The nearest other station, Reno WFO, NV, 3 miles northwest of Sparks and 630 feet higher, has a last frost 3 days earlier (April 28), a first frost 17 days later (October 27), a season 22 days longer.

The first measurable snow (0.1 inch or more) in Sparks usually arrives around December 18, and the last of the season around February 25. Those are the middle dates across the winters of 1991–2020 at Sparks, NV, 1.4 miles away: half of years saw snow earlier, half later. Snow fell in 93% of those winters. The last 32°F night of spring typically comes 65 days after the last snow.

ZIP 89431 is 1 mile from Sparks, NV, which stands at 4,357 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 89431 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.