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Will it freeze in St. Peter in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 31°F (Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST).
Tonight: forecast low 31°F. Freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
4 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 31°F Freeze · Mostly Cloudy
- Fri, Nov 6 27°F Hard freeze · Areas Of Fog
- Sat, Nov 7 34°F Frost possible · Mostly Clear
- Sun, Nov 8 37°F Above 36°F · Mostly Clear
- Mon, Nov 9 37°F Above 36°F · Mostly Clear
- Tue, Nov 10 35°F Frost possible · Partly Cloudy
- Wed, Nov 11 37°F Above 36°F · Partly 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. Peter
The median first fall hard-freeze date (28°F) is October 13, from NOAA’s 1991–2020 Climate Normals at St Peter. 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 30 · May 10 · May 23 | Sep 13 · Sep 27 · Oct 8 | 137 days |
| 32°F freeze | Apr 19 · May 2 · May 14 | Sep 21 · Oct 4 · Oct 16 | 153 days |
| 28°F hard freeze | Apr 8 · Apr 22 · May 5 | Sep 28 · Oct 13 · Oct 26 | 173 days |
Average high temperature by month
1991–2020 normals at St Peter
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. Peter, MN come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: St Peter (station USC00217405, elevation 795 ft), 0.5 mi from St. Peter. 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. Peter
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| North Mankato, MN | 11 mi | Apr 30 | Oct 9 |
| Mankato, MN | 11 mi | Apr 30 | Oct 9 |
| Belle Plaine, MN | 22 mi | May 2 | Oct 5 |
| New Prague, MN | 24 mi | May 2 | Oct 5 |
| New Ulm, MN | 25 mi | Apr 29 | Oct 7 |
| Jordan, MN | 28 mi | May 2 | Oct 5 |
| Waseca, MN | 29 mi | May 2 | Oct 4 |
| Lonsdale, MN | 29 mi | May 5 | Oct 5 |
| Glencoe, MN | 32 mi | Apr 30 | Oct 4 |
| Faribault, MN | 34 mi | May 5 | Oct 5 |
Frequently asked questions
When is the last frost in St. Peter?
On average, the last spring frost (32°F) in St. Peter is around May 2. In about 1 year in 10 it comes after May 14, and in 9 years in 10 it comes after April 19.
When is the first frost in St. Peter?
The first fall frost (32°F) usually arrives around October 4. There’s a 10% chance of a freeze by September 21 and a 90% chance by October 16.
Can it frost in St. Peter 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 10.
What growing zone is St. Peter?
St. Peter is in USDA Plant Hardiness Zone 4b (average annual extreme minimum temperature −25 to −20°F), based on the 2023 USDA map for ZIP code 56082. See growing zones in Minnesota.
More: all Minnesota frost dates · Minnesota growing zones · frost vs. freeze