Willis, TX 77378 Frost Dates
Frost dates for Willis, TX, ZIP 77378
Around 03/11 is the usual last spring frost, about 195 days away. The first fall frost typically arrives around 11/19, about 253 frost-free days later.
The USDA Plant Hardiness Zone Map puts Willis in Zone 9a (20 to 25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 9a around Willis has about 12 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 03/11 isn't a guarantee
03/11 is the middle of 30 years of NOAA records, not a promise. Plant by 02/14 and you're betting against frost in roughly 9 years out of 10. 04/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Willis compares
Willis's growing season runs about 253 days, ranking 7,137 of 40,283 US ZIP codes measured here, longest to shortest. Within TX, it ranks 1,544 of 2,558.
Learn more
local microclimates explains what one yard in Willis can differ from the 77378 normal, and zone vs. frost date explains why Zone 9a and Willis's frost date answer different questions.