Frost Dates for 80642 — Hudson, Colorado

Half of springs at Brighton 3 SE, CO see their last 32°F night by May 3; only one in ten is past it by April 22, and one in ten still has one after May 16. Planting tender crops after May 8 leaves a 30% risk of a frost on them, after May 12 20%, and after May 16 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 67% of the 110 Colorado stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 7 in half of years, as early as September 26 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 9 days later, around October 16; in spring the one-in-ten date for 28°F is May 7, 9 days before the 32°F one. The freeze-free season lasts 155 days in a typical year, longer than at 70% of the 110 Colorado stations; it reaches 172 days one year in ten and falls short of 138 one year in ten. On average 163 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 10 days longer, to about May 13, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 13 and March 16.

July is the warmest month at Brighton 3 SE, CO, averaging 90°F by day and 58°F at night; December is the coldest at 44°F and 16°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 64% of years.

Warmth for growing adds up to 2,923 growing degree days a year (base 50°F), more than at 74% of the 110 Colorado stations. 32% of them (932) have built up by the end of June, and July adds the most, 747. Precipitation totals 14.2 inches a year, most in May (2.4") and least in January (0.4"); May to September bring 60% of it.

The nearest other station, Denver International Airport, CO, 16 miles south of Hudson and 398 feet higher, has a last frost 2 days later (May 5), a first frost 2 days later (October 9), a season 1 day longer.

The first measurable snow (0.1 inch or more) in Hudson usually arrives around October 25, and the last of the season around May 1. Those are the middle dates across the winters of 1991–2020 at Hudson 4.8 WSW, CO, 5.2 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 2 days after the last snow.

ZIP 80642 is 14 miles from Brighton 3 SE, CO, which stands at 5,016 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 80602 (Thornton). The 2023 USDA Plant Hardiness Zone Map lists ZIP 80642 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.