Last spring frost
Apr 17
Frost Dates for Chelan Falls, WA
First fall frost
Oct 22
Growing season
187 days
Hardiness zone
7b
In an average year around Chelan Falls, WA, the last spring frost (32°F) is about Apr 17 and the first fall frost is about Oct 22, giving roughly a 187-day growing season. To be safe most years, wait until Apr 3 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 15 | May 1 | Apr 19 |
| Freeze (32°F) | Apr 30 | Apr 17 | Apr 3 |
| Hard (28°F) | Apr 15 | Mar 29 | Mar 11 |
| Severe (24°F) | Mar 28 | Mar 10 | Feb 24 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 15 | May 9 | May 5 | May 3 | May 1 | Apr 29 | Apr 26 | Apr 24 | Apr 19 |
| 32°F | Apr 30 | Apr 27 | Apr 24 | Apr 21 | Apr 17 | Apr 14 | Apr 12 | Apr 8 | Apr 3 |
| 28°F | Apr 15 | Apr 8 | Apr 3 | Mar 31 | Mar 29 | Mar 25 | Mar 21 | Mar 16 | Mar 11 |
| 24°F | Mar 28 | Mar 20 | Mar 16 | Mar 13 | Mar 10 | Mar 7 | Mar 4 | Mar 2 | Feb 24 |
| 20°F | Mar 14 | Mar 8 | Mar 4 | Mar 2 | Feb 28 | Feb 24 | Feb 20 | Feb 15 | Feb 7 |
| 16°F | Mar 4 | Feb 28 | Feb 23 | Feb 19 | Feb 14 | Feb 9 | Feb 3 | Jan 26 | Jan 13 |
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 1 | Oct 10 | Oct 22 |
| Freeze (32°F) | Oct 9 | Oct 22 | Nov 5 |
| Hard (28°F) | Oct 21 | Nov 4 | Nov 18 |
| Severe (24°F) | Oct 30 | Nov 15 | Nov 30 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 10 | Oct 12 | Oct 16 | Oct 18 | Oct 22 |
| 32°F | Oct 9 | Oct 13 | Oct 17 | Oct 20 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 5 |
| 28°F | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 13 | Nov 18 |
| 24°F | Oct 30 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 24 | Nov 30 |
| 20°F | Nov 10 | Nov 15 | Nov 20 | Nov 24 | Nov 27 | Dec 1 | Dec 5 | Dec 11 | Dec 20 |
| 16°F | Nov 20 | Nov 27 | Dec 1 | Dec 5 | Dec 10 | Dec 16 | Dec 22 | Dec 31 | Jan 9 |
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: Chelan, Wa, about 2.9 miles away@if(!empty($station['elevation_ft'])), at 1,194 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 Chelan Falls, WA?
On average, the last spring frost (32°F) around Chelan Falls, WA is about Apr 17. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 3.
When is the first frost in the fall?
The first fall frost around Chelan Falls, WA typically arrives about Oct 22. 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 17 on average, or Apr 3 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 187 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 98817 Planting calendar → Washington frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026