Frost Dates for 78056 — Mico, Texas

Half of springs at San Antonio/Seaworld, TX see their last 32°F night by February 18; only one in ten is past it by January 18, and one in ten still has one after March 16. Planting tender crops after February 28 leaves a 30% risk of a frost on them, after March 6 20%, and after March 16 10%. The 26 days between the even-odds date and the one-in-ten date is wider than at 84% of the 339 Texas 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 December 9 in half of years, as early as November 17 one year in ten, and holds off past January 13 one year in ten. A hard freeze of 28°F follows 20 days later, around December 29; in spring the one-in-ten date for 28°F is March 3, 13 days before the 32°F one. The freeze-free season lasts 296 days in a typical year, longer than at 85% of the 339 Texas stations; it reaches 334 days one year in ten and falls short of 260 one year in ten. On average 14 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 14 days longer, to about March 4, and return around November 25. A 24°F night is unusual: 38% of winters had one.

August is the warmest month at San Antonio/Seaworld, TX, averaging 99°F by day and 74°F at night; January is the coldest at 65°F and 43°F. From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 64% of years and March still brings one in 28% of years.

Warmth for growing adds up to 7,892 growing degree days a year (base 50°F), more than at 87% of the 351 Texas stations. 43% of them (3,402) have built up by the end of June, and August adds the most, 1,130. Precipitation totals 31.5 inches a year, most in May (4.0") and least in February (1.8"); May to September bring 49% of it.

The nearest other station, Boerne, TX, 20 miles northeast of Mico and 505 feet higher, has a last frost 25 days later (March 15), a first frost 26 days earlier (November 13), a season 53 days shorter.

Measurable snow is rare here: only 0 of 19 winters from 1991 to 2020 recorded 0.1 inch or more at Riomedina, TX, 7.5 miles away, so there is no typical first-snow date to plan around.

ZIP 78056 is 14 miles from San Antonio/Seaworld, TX, which stands at 940 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 8 other ZIP codes share the station; its figures are presented in full for 78245 (San Antonio). The 2023 USDA Plant Hardiness Zone Map lists ZIP 78056 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°C) over 1991–2020; a zone describes winter lows, not frost dates.