Last spring frost
Jun 2
Frost Dates for Encampment, WY
First fall frost
Sep 12
Growing season
101 days
Hardiness zone
5a
In an average year around Encampment, WY, the last spring frost (32°F) is about Jun 2 and the first fall frost is about Sep 12, giving roughly a 101-day growing season. To be safe most years, wait until May 15 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) | Jul 1 | Jun 17 | May 31 |
| Freeze (32°F) | Jun 21 | Jun 2 | May 15 |
| Hard (28°F) | Jun 6 | May 15 | Apr 30 |
| Severe (24°F) | May 22 | May 3 | Apr 15 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jul 1 | Jun 28 | Jun 24 | Jun 21 | Jun 17 | Jun 14 | Jun 10 | Jun 5 | May 31 |
| 32°F | Jun 21 | Jun 15 | Jun 9 | Jun 5 | Jun 2 | May 29 | May 25 | May 21 | May 15 |
| 28°F | Jun 6 | Jun 1 | May 25 | May 20 | May 15 | May 11 | May 8 | May 4 | Apr 30 |
| 24°F | May 22 | May 14 | May 10 | May 7 | May 3 | Apr 30 | Apr 26 | Apr 22 | Apr 15 |
| 20°F | May 13 | May 6 | May 1 | Apr 26 | Apr 22 | Apr 16 | Apr 12 | Apr 7 | Apr 3 |
| 16°F | May 2 | Apr 25 | Apr 17 | Apr 11 | Apr 6 | Apr 2 | Mar 30 | Mar 25 | Mar 17 |
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) | Aug 3 | Aug 30 | Sep 18 |
| Freeze (32°F) | Aug 12 | Sep 12 | Oct 1 |
| Hard (28°F) | Sep 5 | Sep 29 | Oct 15 |
| Severe (24°F) | Sep 26 | Oct 11 | Oct 25 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Aug 3 | Aug 8 | Aug 15 | Aug 22 | Aug 30 | Sep 3 | Sep 7 | Sep 11 | Sep 18 |
| 32°F | Aug 12 | Aug 22 | Aug 30 | Sep 7 | Sep 12 | Sep 18 | Sep 21 | Sep 26 | Oct 1 |
| 28°F | Sep 5 | Sep 18 | Sep 23 | Sep 26 | Sep 29 | Oct 2 | Oct 5 | Oct 10 | Oct 15 |
| 24°F | Sep 26 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 14 | Oct 18 | Oct 21 | Oct 25 |
| 20°F | Oct 1 | Oct 8 | Oct 13 | Oct 16 | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Nov 2 |
| 16°F | Oct 9 | Oct 17 | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 3 | Nov 7 | Nov 12 |
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: Saratoga, Wy, about 20.8 miles away@if(!empty($station['elevation_ft'])), at 6,790 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 Encampment, WY?
On average, the last spring frost (32°F) around Encampment, WY is about Jun 2. In cooler years it can run later, so for a safer bet many gardeners wait until May 15.
When is the first frost in the fall?
The first fall frost around Encampment, WY typically arrives about Sep 12. 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 Jun 2 on average, or May 15 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 101 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 82325 Planting calendar → Wyoming frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026