Last spring frost
Apr 18
Frost Dates for Columbia City, OR
First fall frost
Nov 7
Growing season
201 days
Hardiness zone
8b
In an average year around Columbia City, OR, the last spring frost (32°F) is about Apr 18 and the first fall frost is about Nov 7, giving roughly a 201-day growing season. To be safe most years, wait until Mar 20 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) | Jun 9 | May 6 | Apr 18 |
| Freeze (32°F) | May 26 | Apr 18 | Mar 20 |
| Hard (28°F) | May 6 | Mar 24 | Feb 20 |
| Severe (24°F) | Apr 6 | Feb 24 | Jan 7 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 9 | May 29 | May 19 | May 12 | May 6 | May 2 | Apr 29 | Apr 25 | Apr 18 |
| 32°F | May 26 | May 9 | Apr 30 | Apr 25 | Apr 18 | Apr 12 | Apr 4 | Mar 30 | Mar 20 |
| 28°F | May 6 | Apr 20 | Apr 6 | Mar 30 | Mar 24 | Mar 16 | Mar 8 | Feb 28 | Feb 20 |
| 24°F | Apr 6 | Mar 21 | Mar 9 | Mar 1 | Feb 24 | Feb 17 | Feb 9 | Jan 27 | Jan 7 |
| 20°F | Mar 9 | Feb 25 | Feb 17 | Feb 10 | Jan 31 | Jan 18 | Jan 7 | Dec 30 | Dec 12 |
| 16°F | Feb 23 | Feb 12 | Feb 3 | Jan 24 | Jan 14 | Jan 2 | Dec 27 | Dec 14 | Dec 5 |
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 6 | Oct 24 | Nov 10 |
| Freeze (32°F) | Oct 21 | Nov 7 | Nov 26 |
| Hard (28°F) | Nov 3 | Nov 24 | Dec 16 |
| Severe (24°F) | Nov 15 | Dec 12 | Jan 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 6 | Oct 12 | Oct 17 | Oct 21 | Oct 24 | Oct 28 | Nov 1 | Nov 5 | Nov 10 |
| 32°F | Oct 21 | Oct 27 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 16 | Nov 21 | Nov 26 |
| 28°F | Nov 3 | Nov 8 | Nov 13 | Nov 20 | Nov 24 | Nov 29 | Dec 3 | Dec 9 | Dec 16 |
| 24°F | Nov 15 | Nov 25 | Dec 1 | Dec 7 | Dec 12 | Dec 18 | Dec 24 | Dec 30 | Jan 16 |
| 20°F | Nov 24 | Dec 3 | Dec 12 | Dec 20 | Dec 27 | Jan 1 | Jan 9 | Jan 26 | Feb 14 |
| 16°F | Nov 26 | Dec 6 | Dec 16 | Dec 25 | Dec 31 | Jan 9 | Jan 20 | Feb 1 | Feb 13 |
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: Saint Helens Rfd, Or, about 4.5 miles away@if(!empty($station['elevation_ft'])), at 269 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 Columbia City, OR?
On average, the last spring frost (32°F) around Columbia City, OR is about Apr 18. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 20.
When is the first frost in the fall?
The first fall frost around Columbia City, OR typically arrives about Nov 7. 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 Apr 18 on average, or Mar 20 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 201 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 97018 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026