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Will it freeze in Mandan in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 25°F (Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST).
Tonight: forecast low 25°F. Hard freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
6 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 25°F Hard freeze · Partly Cloudy
- Fri, Nov 6 30°F Freeze · Mostly Clear
- Sat, Nov 7 31°F Freeze · Mostly Clear
- Sun, Nov 8 40°F Above 36°F · Partly Cloudy
- Mon, Nov 9 32°F Freeze · Partly Cloudy
- Tue, Nov 10 35°F Frost possible · Partly Cloudy
- Wed, Nov 11 35°F Frost possible · Mostly Clear
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 Mandan
The median first fall hard-freeze date (28°F) is October 4, from NOAA’s 1991–2020 Climate Normals at Mandan Experiment Station. 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 | May 10 · May 23 · Jun 4 | Sep 6 · Sep 19 · Oct 1 | 119 days |
| 32°F freeze | May 1 · May 13 · May 26 | Sep 15 · Sep 27 · Oct 10 | 136 days |
| 28°F hard freeze | Apr 19 · May 3 · May 17 | Sep 23 · Oct 4 · Oct 19 | 154 days |
Average high temperature by month
1991–2020 normals at Mandan Experiment Station
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 Mandan, ND come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Mandan Experiment Station (station USC00325479, elevation 1,750 ft), 1.6 mi from Mandan. 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 Mandan
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Bismarck, ND | 5.6 mi | May 10 | Sep 30 |
| Dickinson, ND | 90 mi | May 20 | Sep 22 |
| Minot, ND | 99 mi | May 10 | Oct 1 |
| Jamestown, ND | 104 mi | May 8 | Sep 29 |
| Devils Lake, ND | 129 mi | May 6 | Oct 5 |
| Watford City, ND | 130 mi | May 9 | Sep 27 |
| Valley City, ND | 136 mi | May 13 | Sep 26 |
| Aberdeen, SD | 149 mi | May 8 | Sep 29 |
| Williston, ND | 160 mi | May 21 | Sep 21 |
| Pierre, SD | 171 mi | May 6 | Oct 3 |
Frequently asked questions
When is the last frost in Mandan?
On average, the last spring frost (32°F) in Mandan is around May 13. In about 1 year in 10 it comes after May 26, and in 9 years in 10 it comes after May 1.
When is the first frost in Mandan?
The first fall frost (32°F) usually arrives around September 27. There’s a 10% chance of a freeze by September 15 and a 90% chance by October 10.
Can it frost in Mandan 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 23.
What growing zone is Mandan?
Mandan is in USDA Plant Hardiness Zone 4a (average annual extreme minimum temperature −30 to −25°F), based on the 2023 USDA map for ZIP code 58505. See growing zones in North Dakota.
More: all North Dakota frost dates · North Dakota growing zones · UV index today in Mandan · frost vs. freeze