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Will it freeze in Jamestown in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 23°F (Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST).
Tonight: forecast low 23°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 23°F Hard freeze · Mostly Cloudy
- Fri, Nov 6 30°F Freeze · Partly Cloudy
- Sat, Nov 7 33°F Frost possible · Partly Cloudy
- Sun, Nov 8 39°F Above 36°F · Partly Cloudy
- Mon, Nov 9 33°F Frost possible · Mostly Clear
- Tue, Nov 10 33°F Frost possible · Partly Cloudy
- Wed, Nov 11 34°F Frost possible · 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 Jamestown
The median first fall hard-freeze date (28°F) is October 7, from NOAA’s 1991–2020 Climate Normals at Jamestown State Hosp. 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 6 · May 17 · May 31 | Sep 10 · Sep 21 · Oct 1 | 126 days |
| 32°F freeze | Apr 26 · May 8 · May 21 | Sep 17 · Sep 29 · Oct 11 | 143 days |
| 28°F hard freeze | Apr 16 · Apr 30 · May 12 | Sep 26 · Oct 7 · Oct 21 | 161 days |
Average high temperature by month
1991–2020 normals at Jamestown State Hosp
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 Jamestown, ND come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Jamestown State Hosp (station USC00324418, elevation 1,467 ft), 1.6 mi from Jamestown. 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 Jamestown
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Valley City, ND | 32 mi | May 13 | Sep 26 |
| Devils Lake, ND | 84 mi | May 6 | Oct 5 |
| West Fargo, ND | 85 mi | May 4 | Oct 2 |
| Horace, ND | 85 mi | May 4 | Oct 2 |
| Fargo, ND | 88 mi | May 4 | Oct 2 |
| Moorhead, MN | 92 mi | May 5 | Oct 3 |
| Bismarck, ND | 98 mi | May 10 | Sep 30 |
| Aberdeen, SD | 100 mi | May 8 | Sep 29 |
| Grand Forks, ND | 103 mi | May 10 | Oct 1 |
| Mandan, ND | 104 mi | May 13 | Sep 27 |
Frequently asked questions
When is the last frost in Jamestown?
On average, the last spring frost (32°F) in Jamestown is around May 8. In about 1 year in 10 it comes after May 21, and in 9 years in 10 it comes after April 26.
When is the first frost in Jamestown?
The first fall frost (32°F) usually arrives around September 29. There’s a 10% chance of a freeze by September 17 and a 90% chance by October 11.
Can it frost in Jamestown 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 17.
What growing zone is Jamestown?
Jamestown 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 58405. See growing zones in North Dakota.
More: all North Dakota frost dates · North Dakota growing zones · frost vs. freeze