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Will it freeze in Happy Valley in the next 7 nights?
No overnight lows at or below 32°F are forecast in Happy Valley during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 43°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 43°F Above 36°F · Mostly Cloudy
- Fri, Nov 6 48°F Above 36°F · Light Rain Likely
- Sat, Nov 7 50°F Above 36°F · Light Rain
- Sun, Nov 8 43°F Above 36°F · Mostly Cloudy
- Mon, Nov 9 48°F Above 36°F · Light Rain Likely
- Tue, Nov 10 50°F Above 36°F · Chance Light Rain
- Wed, Nov 11 47°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 Happy Valley
The median first fall hard-freeze date (28°F) is December 8, from NOAA’s 1991–2020 Climate Normals at Oregon City. 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 | Mar 26 · Apr 15 · May 4 | Oct 16 · Oct 31 · Nov 20 | 198 days |
| 32°F freeze | Feb 19 · Mar 18 · Apr 11 | Oct 30 · Nov 18 · Dec 12 | 244 days |
| 28°F hard freeze | Jan 1 · Feb 12 · Mar 7 | Nov 16 · Dec 8 · Jan 5 | 302 days |
Average high temperature by month
1991–2020 normals at Oregon City
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 Happy Valley, OR come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Oregon City (station USC00356334, elevation 167 ft), 7.1 mi from Happy Valley. 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 Happy Valley
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Gladstone, OR | 5.0 mi | Mar 18 | Nov 18 |
| Milwaukie, OR | 5.6 mi | Feb 25 | Dec 1 |
| Gresham, OR | 5.6 mi | Mar 16 | Nov 20 |
| Oregon City, OR | 7.5 mi | Mar 18 | Nov 18 |
| West Linn, OR | 8.1 mi | Mar 18 | Nov 18 |
| Fairview, OR | 8.7 mi | Mar 16 | Nov 20 |
| Troutdale, OR | 9.3 mi | Mar 26 | Nov 17 |
| Lake Oswego, OR | 9.3 mi | Mar 18 | Nov 18 |
| Portland, OR | 9.9 mi | Feb 25 | Dec 1 |
| Sandy, OR | 12 mi | Mar 27 | Nov 18 |
Frequently asked questions
When is the last frost in Happy Valley?
On average, the last spring frost (32°F) in Happy Valley is around March 18. In about 1 year in 10 it comes after April 11, and in 9 years in 10 it comes after February 19.
When is the first frost in Happy Valley?
The first fall frost (32°F) usually arrives around November 18. There’s a 10% chance of a freeze by October 30 and a 90% chance by December 12.
Can it frost in Happy Valley 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 April 15.
What growing zone is Happy Valley?
Happy Valley 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 97086. See growing zones in Oregon.
More: all Oregon frost dates · Oregon growing zones · UV index today in Happy Valley · frost vs. freeze