Last spring frost
Mar 23
Frost Dates for Lookingglass, OR
First fall frost
Nov 18
Growing season
237 days
Hardiness zone
9a
In an average year around Lookingglass, OR, the last spring frost (32°F) is about Mar 23 and the first fall frost is about Nov 18, giving roughly a 237-day growing season. To be safe most years, wait until Feb 25 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 9 | Apr 21 | Mar 31 |
| Freeze (32°F) | Apr 16 | Mar 23 | Feb 25 |
| Hard (28°F) | Mar 21 | Feb 20 | Dec 31 |
| Severe (24°F) | Feb 26 | Jan 11 | Dec 6 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 9 | May 3 | Apr 29 | Apr 25 | Apr 21 | Apr 17 | Apr 12 | Apr 8 | Mar 31 |
| 32°F | Apr 16 | Apr 7 | Apr 1 | Mar 28 | Mar 23 | Mar 19 | Mar 13 | Mar 4 | Feb 25 |
| 28°F | Mar 21 | Mar 10 | Mar 1 | Feb 25 | Feb 20 | Feb 11 | Feb 1 | Jan 20 | Dec 31 |
| 24°F | Feb 26 | Feb 17 | Feb 8 | Jan 26 | Jan 11 | Jan 3 | Dec 27 | Dec 19 | Dec 6 |
| 20°F | Feb 19 | Jan 25 | Jan 9 | Jan 1 | Dec 30 | Dec 25 | Dec 22 | Dec 17 | Dec 9 |
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 8 | Oct 25 | Nov 17 |
| Freeze (32°F) | Oct 24 | Nov 18 | Dec 17 |
| Hard (28°F) | Nov 8 | Dec 11 | Jan 31 |
| Severe (24°F) | Nov 27 | Dec 27 | Feb 15 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 8 | Oct 14 | Oct 18 | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 8 | Nov 17 |
| 32°F | Oct 24 | Oct 31 | Nov 5 | Nov 11 | Nov 18 | Nov 24 | Nov 30 | Dec 6 | Dec 17 |
| 28°F | Nov 8 | Nov 18 | Nov 28 | Dec 3 | Dec 11 | Dec 19 | Dec 26 | Jan 7 | Jan 31 |
| 24°F | Nov 27 | Dec 5 | Dec 13 | Dec 21 | Dec 27 | Jan 2 | Jan 11 | Feb 1 | Feb 15 |
| 20°F | Dec 7 | Dec 13 | Dec 20 | Dec 22 | Dec 27 | Dec 31 | Jan 5 | Jan 21 | Feb 15 |
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: Roseburg Kqen, Or, about 6.2 miles away@if(!empty($station['elevation_ft'])), at 425 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 Lookingglass, OR?
On average, the last spring frost (32°F) around Lookingglass, OR is about Mar 23. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 25.
When is the first frost in the fall?
The first fall frost around Lookingglass, OR typically arrives about Nov 18. 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 23 on average, or Feb 25 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 237 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 97471 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026