Blair, WI 54616 Frost Dates
Frost dates for Blair, WI, ZIP 54616
The last spring frost here typically falls around 05/09, about 254 days from today. The first fall frost typically arrives around 10/01, about 143 frost-free days later.
Blair sits in USDA Zone 4b (-25 to -20°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 4b around Blair has about 5 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 05/09 isn't a guarantee
05/09 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 05/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Blair compares
Blair's growing season runs about 143 days, ranking 36,558 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 692 of 860.
Learn more
local microclimates explains what one yard in Blair can differ from the 54616 normal, and zone vs. frost date explains why Zone 4b and Blair's frost date answer different questions.