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Will it freeze in Monmouth in the next 7 nights?
No overnight lows at or below 32°F are forecast in Monmouth during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 41°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM PST to Fri, Nov 6, 6:00 AM PST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 41°F Above 36°F · Patchy Fog
- Fri, Nov 6 46°F Above 36°F · Chance Light Rain then Mostly Cloudy
- Sat, Nov 7 49°F Above 36°F · Light Rain
- Sun, Nov 8 41°F Above 36°F · Mostly Cloudy
- Mon, Nov 9 46°F Above 36°F · Light Rain Likely
- Tue, Nov 10 48°F Above 36°F · Chance Light Rain
- Wed, Nov 11 45°F Above 36°F · Chance Light Rain
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 Monmouth
The median first fall hard-freeze date (28°F) is November 20, from NOAA’s 1991–2020 Climate Normals at Dallas 2 NE. 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 19 · May 6 · May 23 | Sep 29 · Oct 13 · Nov 1 | 159 days |
| 32°F freeze | Mar 21 · Apr 16 · May 5 | Oct 13 · Nov 1 · Nov 22 | 199 days |
| 28°F hard freeze | Feb 2 · Mar 7 · Apr 8 | Oct 31 · Nov 20 · Dec 15 | 258 days |
Average high temperature by month
1991–2020 normals at Dallas 2 NE
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 Monmouth, OR come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Dallas 2 NE (station USC00352112, elevation 290 ft), 7.3 mi from Monmouth. 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 Monmouth
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Independence, OR | 1.9 mi | Apr 16 | Nov 1 |
| Dallas, OR | 6.2 mi | Apr 16 | Nov 1 |
| Salem, OR | 11 mi | Apr 3 | Nov 1 |
| Keizer, OR | 14 mi | Apr 3 | Nov 1 |
| Albany, OR | 17 mi | Apr 17 | Oct 28 |
| Sheridan, OR | 19 mi | Apr 16 | Nov 1 |
| Corvallis, OR | 20 mi | Apr 17 | Oct 28 |
| Stayton, OR | 21 mi | Mar 29 | Nov 6 |
| Philomath, OR | 22 mi | May 15 | Oct 8 |
| Silverton, OR | 24 mi | Mar 28 | Nov 10 |
Frequently asked questions
When is the last frost in Monmouth?
On average, the last spring frost (32°F) in Monmouth is around April 16. In about 1 year in 10 it comes after May 5, and in 9 years in 10 it comes after March 21.
When is the first frost in Monmouth?
The first fall frost (32°F) usually arrives around November 1. There’s a 10% chance of a freeze by October 13 and a 90% chance by November 22.
Can it frost in Monmouth 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 6.
What growing zone is Monmouth?
Monmouth is in USDA Plant Hardiness Zone 8b (average annual extreme minimum temperature 15 to 20°F), based on the 2023 USDA map for ZIP code 97351. See growing zones in Oregon.
More: all Oregon frost dates · Oregon growing zones · frost vs. freeze