St. Louis, MI 48880 Frost Dates
Frost dates for St. Louis, MI, ZIP 48880
Typically, the last spring freeze lands around 05/01, roughly 246 days out. The first fall frost typically arrives around 10/13, about 164 frost-free days later.
St. Louis sits in USDA Zone 6a (-10 to -5°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 6a around St. Louis has about 7 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.
How much risk comes with planting early here
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/17 and you're betting against frost in roughly 9 years out of 10. 05/19 is the safer bet, historically only a 1-in-10 chance of frost that late.
How St. Louis compares
At roughly 164 frost-free days, St. Louis places 30,896 of 40,283 ZIP codes in this dataset. Within MI, it ranks 481 of 1,153.
Learn more
zone vs. frost date explains why Zone 6a and St. Louis's frost date answer different questions, and the frost range explains how to read the range around St. Louis's dates instead of trusting one.