Lake St. Louis, MO 63367 Frost Dates
Lake St. Louis, MO: when does the frost end?
The last spring frost here typically falls around 04/10, about 225 days from today. Fall's first freeze usually shows up around 10/26, roughly 199 days after the last spring frost.
Zone 6b (-5 to 0°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Lake St. Louis, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Lake St. Louis's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/10 isn't a guarantee
04/10 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/26 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/26 and only about 1 year in 10 sees frost after that.
Lake St. Louis against the rest of the dataset
Lake St. Louis's growing season runs about 199 days, ranking 18,040 of 40,283 US ZIP codes measured here, longest to shortest. Within MO, it ranks 414 of 1,129.
Learn more
Before leaning on 63367's figures: local microclimates explains what one yard in Lake St. Louis can differ from the 63367 normal, while zone vs. frost date explains why Zone 6b and Lake St. Louis's frost date answer different questions.