St. Louis, MO 63104 Frost Dates
Frost dates for St. Louis, MO, ZIP 63104
Around 04/01 is the usual last spring frost, about 216 days away. The first fall frost typically arrives around 11/04, about 218 frost-free days later.
St. Louis sits in USDA Zone 7a (0 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 7a around St. Louis has about 10 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.
The actual range around St. Louis's last frost
04/01 is the middle of 30 years of NOAA records, not a promise. Plant by 03/14 and you're betting against frost in roughly 9 years out of 10. 04/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How St. Louis compares
At roughly 218 frost-free days, St. Louis places 13,144 of 40,283 ZIP codes in this dataset. Within MO, it ranks 48 of 1,129.
Learn more
the frost range explains how to read the range around St. Louis's dates instead of trusting one, and local microclimates explains what one yard in St. Louis can differ from the 63104 normal.