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Will it freeze in Polson in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 29°F (Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST).
Tonight: forecast low 29°F. Freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
5 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 29°F Freeze · Slight Chance Light Rain then Partly Cloudy
- Fri, Nov 6 35°F Frost possible · Mostly Cloudy
- Sat, Nov 7 36°F Frost possible · Partly Cloudy
- Sun, Nov 8 33°F Frost possible · Mostly Cloudy
- Mon, Nov 9 34°F Frost possible · Mostly Cloudy
- Tue, Nov 10 38°F Above 36°F · Slight Chance Light Rain
- Wed, Nov 11 38°F Above 36°F · 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 Polson
The median first fall hard-freeze date (28°F) is October 16, from NOAA’s 1991–2020 Climate Normals at Polson. 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 11 · May 28 · Jun 16 | Sep 9 · Sep 26 · Oct 7 | 118 days |
| 32°F freeze | Apr 27 · May 10 · May 26 | Sep 22 · Oct 5 · Oct 19 | 147 days |
| 28°F hard freeze | Apr 7 · Apr 28 · May 13 | Oct 1 · Oct 16 · Nov 1 | 171 days |
Average high temperature by month
1991–2020 normals at Polson
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 Polson, MT come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Polson (station USC00246635, elevation 3,010 ft), 2.4 mi from Polson. 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 Polson
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Kalispell, MT | 37 mi | May 31 | Sep 10 |
| Columbia Falls, MT | 47 mi | May 31 | Sep 10 |
| Whitefish, MT | 53 mi | May 16 | Sep 25 |
| Missoula, MT | 57 mi | May 10 | Oct 1 |
| Hamilton, MT | 99 mi | May 21 | Sep 22 |
| Sandpoint, ID | 119 mi | May 8 | Sep 28 |
| Anaconda, MT | 120 mi | Jun 1 | Sep 14 |
| Coeur d'Alene, ID | 124 mi | Apr 22 | Oct 18 |
| Hayden, ID | 124 mi | Apr 22 | Oct 18 |
| Helena, MT | 125 mi | May 9 | Sep 30 |
Frequently asked questions
When is the last frost in Polson?
On average, the last spring frost (32°F) in Polson is around May 10. In about 1 year in 10 it comes after May 26, and in 9 years in 10 it comes after April 27.
When is the first frost in Polson?
The first fall frost (32°F) usually arrives around October 5. There’s a 10% chance of a freeze by September 22 and a 90% chance by October 19.
Can it frost in Polson 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 28.
What growing zone is Polson?
Polson 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 59860. See growing zones in Montana.
More: all Montana frost dates · Montana growing zones · frost vs. freeze