Last spring frost
May 13
Frost Dates for Salt Lake City, UT
First fall frost
Oct 7
Growing season
146 days
Hardiness zone
6b
In an average year around Salt Lake City, UT, the last spring frost (32°F) is about May 13 and the first fall frost is about Oct 7, giving roughly a 146-day growing season. To be safe most years, wait until Apr 27 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 13 | May 31 | May 13 |
| Freeze (32°F) | May 31 | May 13 | Apr 27 |
| Hard (28°F) | May 15 | Apr 28 | Apr 10 |
| Severe (24°F) | Apr 30 | Apr 7 | Mar 20 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 13 | Jun 8 | Jun 4 | Jun 2 | May 31 | May 27 | May 23 | May 19 | May 13 |
| 32°F | May 31 | May 25 | May 20 | May 16 | May 13 | May 9 | May 5 | May 2 | Apr 27 |
| 28°F | May 15 | May 9 | May 4 | Apr 30 | Apr 28 | Apr 24 | Apr 20 | Apr 16 | Apr 10 |
| 24°F | Apr 30 | Apr 22 | Apr 15 | Apr 12 | Apr 7 | Apr 5 | Apr 1 | Mar 28 | Mar 20 |
| 20°F | Apr 9 | Apr 4 | Mar 30 | Mar 24 | Mar 19 | Mar 14 | Mar 10 | Mar 6 | Mar 1 |
| 16°F | Mar 22 | Mar 13 | Mar 9 | Mar 5 | Mar 2 | Feb 28 | Feb 23 | Feb 19 | Feb 12 |
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) | Sep 13 | Sep 27 | Oct 9 |
| Freeze (32°F) | Sep 26 | Oct 7 | Oct 22 |
| Hard (28°F) | Oct 4 | Oct 19 | Nov 2 |
| Severe (24°F) | Oct 15 | Oct 30 | Nov 13 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 13 | Sep 19 | Sep 22 | Sep 25 | Sep 27 | Sep 30 | Oct 2 | Oct 5 | Oct 9 |
| 32°F | Sep 26 | Sep 30 | Oct 2 | Oct 4 | Oct 7 | Oct 9 | Oct 13 | Oct 16 | Oct 22 |
| 28°F | Oct 4 | Oct 9 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 2 |
| 24°F | Oct 15 | Oct 20 | Oct 24 | Oct 27 | Oct 30 | Nov 2 | Nov 5 | Nov 9 | Nov 13 |
| 20°F | Oct 25 | Oct 31 | Nov 3 | Nov 7 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 25 |
| 16°F | Nov 4 | Nov 10 | Nov 15 | Nov 18 | Nov 20 | Nov 24 | Nov 26 | Nov 30 | Dec 5 |
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: City Creek Wtp, Ut, about 1.1 miles away@if(!empty($station['elevation_ft'])), at 5,340 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 Salt Lake City, UT?
On average, the last spring frost (32°F) around Salt Lake City, UT is about May 13. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 27.
When is the first frost in the fall?
The first fall frost around Salt Lake City, UT typically arrives about Oct 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 May 13 on average, or Apr 27 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 146 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 84103 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026