Last spring frost
Mar 24
Frost Dates for Cascade Locks, OR
First fall frost
Nov 20
Growing season
242 days
Hardiness zone
8a
In an average year around Cascade Locks, OR, the last spring frost (32°F) is about Mar 24 and the first fall frost is about Nov 20, giving roughly a 242-day growing season. To be safe most years, wait until Feb 28 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 6 | Apr 19 | Apr 1 |
| Freeze (32°F) | Apr 16 | Mar 24 | Feb 28 |
| Hard (28°F) | Mar 21 | Feb 24 | Jan 10 |
| Severe (24°F) | Feb 27 | Jan 28 | Dec 13 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 6 | May 1 | Apr 27 | Apr 23 | Apr 19 | Apr 15 | Apr 11 | Apr 6 | Apr 1 |
| 32°F | Apr 16 | Apr 5 | Mar 31 | Mar 29 | Mar 24 | Mar 20 | Mar 14 | Mar 9 | Feb 28 |
| 28°F | Mar 21 | Mar 13 | Mar 6 | Feb 28 | Feb 24 | Feb 18 | Feb 10 | Jan 31 | Jan 10 |
| 24°F | Feb 27 | Feb 19 | Feb 14 | Feb 5 | Jan 28 | Jan 17 | Jan 7 | Dec 31 | Dec 13 |
| 20°F | Feb 18 | Feb 12 | Feb 2 | Jan 23 | Jan 11 | Jan 2 | Dec 26 | Dec 16 | Dec 6 |
| 16°F | Feb 11 | Feb 2 | Jan 25 | Jan 11 | Jan 1 | Dec 28 | Dec 18 | Dec 13 | Dec 7 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 18 | Nov 2 | Nov 23 |
| Freeze (32°F) | Nov 1 | Nov 20 | Dec 12 |
| Hard (28°F) | Nov 13 | Dec 9 | Jan 7 |
| Severe (24°F) | Nov 26 | Dec 26 | Feb 10 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 18 | Oct 22 | Oct 26 | Oct 30 | Nov 2 | Nov 6 | Nov 10 | Nov 15 | Nov 23 |
| 32°F | Nov 1 | Nov 7 | Nov 11 | Nov 15 | Nov 20 | Nov 25 | Nov 30 | Dec 5 | Dec 12 |
| 28°F | Nov 13 | Nov 23 | Nov 30 | Dec 5 | Dec 9 | Dec 16 | Dec 21 | Dec 28 | Jan 7 |
| 24°F | Nov 26 | Dec 5 | Dec 11 | Dec 18 | Dec 26 | Jan 1 | Jan 7 | Jan 18 | Feb 10 |
| 20°F | Nov 30 | Dec 7 | Dec 14 | Dec 23 | Dec 30 | Jan 4 | Jan 13 | Feb 1 | Feb 15 |
| 16°F | Dec 4 | Dec 10 | Dec 14 | Dec 22 | Dec 29 | Jan 1 | Jan 11 | Jan 30 | Feb 7 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Cascade Locks, Or, about 4.7 miles away@if(!empty($station['elevation_ft'])), at 142 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Cascade Locks, OR?
On average, the last spring frost (32°F) around Cascade Locks, OR is about Mar 24. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 28.
When is the first frost in the fall?
The first fall frost around Cascade Locks, OR typically arrives about Nov 20. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Mar 24 on average, or Feb 28 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 242 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 97014 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026