Frost Dates for 79830 — Alpine, Texas

Half of springs at Marathon, TX see their last 32°F night by April 7; only one in ten is past it by March 19, and one in ten still has one after April 26. Planting tender crops after April 15 leaves a 30% risk of a frost on them, after April 20 20%, and after April 26 10%. The 19 days between the even-odds date and the one-in-ten date is narrower than at 63% of the 339 Texas stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 1 in half of years, as early as October 18 one year in ten, and holds off past November 13 one year in ten. A hard freeze of 28°F follows 7 days later, around November 8; in spring the one-in-ten date for 28°F is April 11, 15 days before the 32°F one. The freeze-free season lasts 205 days in a typical year, shorter than at 93% of the 339 Texas stations; it reaches 228 days one year in ten and falls short of 183 one year in ten. On average 75 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 13 days longer, to about April 20, and return around October 23. Severe cold of 16°F or below comes in 98% of winters, usually between December 7 and February 5.

July is the warmest month at Marathon, TX, averaging 91°F by day and 62°F at night; January is the coldest at 62°F and 27°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 69% of years.

Warmth for growing adds up to 4,889 growing degree days a year (base 50°F), fewer than at 92% of the 351 Texas stations. 42% of them (2,066) have built up by the end of June, and July adds the most, 823. Precipitation totals 12.8 inches a year, most in July (2.3") and least in February (0.3"); May to September bring 69% of it.

The nearest other station, Marfa 3W, TX, 37 miles northwest of Alpine and 801 feet higher, has a last frost 7 days later (April 14), a first frost 5 days earlier (October 27), a season 9 days shorter.

Measurable snow is rare here: only 5 of 26 winters from 1991 to 2020 recorded 0.1 inch or more at Marathon, TX, 21.5 miles away, so there is no typical first-snow date to plan around.

ZIP 79830 is 22 miles from Marathon, TX, which stands at 3,989 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 79830 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.