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Will it freeze in St. Louis in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 32°F (Fri, Nov 6, 6:00 PM EST to Sat, Nov 7, 6:00 AM EST).
Tonight: forecast low 36°F. Frost possible.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
6 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 36°F Frost possible · Chance Rain Showers then Mostly Cloudy
- Fri, Nov 6 32°F Freeze · Slight Chance Rain Showers
- Sat, Nov 7 30°F Freeze · Mostly Clear
- Sun, Nov 8 32°F Freeze · Mostly Clear
- Mon, Nov 9 40°F Above 36°F · Mostly Clear
- Tue, Nov 10 34°F Frost possible · Mostly Clear
- Wed, Nov 11 32°F Freeze · Mostly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in St. Louis
The median first fall hard-freeze date (28°F) is October 28, from NOAA’s 1991–2020 Climate Normals at Alma. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Apr 29 · May 14 · May 29 | Sep 20 · Oct 2 · Oct 15 | 140 days |
| 32°F freeze | Apr 17 · May 1 · May 19 | Sep 29 · Oct 13 · Oct 30 | 164 days |
| 28°F hard freeze | Apr 4 · Apr 20 · May 6 | Oct 10 · Oct 28 · Nov 9 | 188 days |
Average high temperature by month
1991–2020 normals at Alma
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for St. Louis, MI come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Alma (station USC00200146, elevation 729 ft), 2.4 mi from St. Louis. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near St. Louis
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Alma, MI | 3.1 mi | May 1 | Oct 13 |
| Mount Pleasant, MI | 16 mi | Apr 30 | Oct 20 |
| Midland, MI | 24 mi | Apr 29 | Oct 16 |
| St. Johns, MI | 29 mi | Apr 28 | Oct 24 |
| Saginaw, MI | 33 mi | Apr 29 | Oct 21 |
| Greenville, MI | 36 mi | May 18 | Sep 28 |
| Owosso, MI | 36 mi | May 1 | Oct 15 |
| Ionia, MI | 38 mi | May 3 | Oct 12 |
| Belding, MI | 38 mi | May 18 | Sep 28 |
| Bay City, MI | 39 mi | Apr 27 | Oct 20 |
Frequently asked questions
When is the last frost in St. Louis?
On average, the last spring frost (32°F) in St. Louis is around May 1. In about 1 year in 10 it comes after May 19, and in 9 years in 10 it comes after April 17.
When is the first frost in St. Louis?
The first fall frost (32°F) usually arrives around October 13. There’s a 10% chance of a freeze by September 29 and a 90% chance by October 30.
Can it frost in St. Louis after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 14.
What growing zone is St. Louis?
St. Louis is in USDA Plant Hardiness Zone 6a (average annual extreme minimum temperature −10 to −5°F), based on the 2023 USDA map for ZIP code 48880. See growing zones in Michigan.
More: all Michigan frost dates · Michigan growing zones · frost vs. freeze