Last spring frost
Apr 29
Frost Dates for South Ogden, UT
First fall frost
Oct 20
Growing season
172 days
Hardiness zone
7a
In an average year around South Ogden, UT, the last spring frost (32°F) is about Apr 29 and the first fall frost is about Oct 20, giving roughly a 172-day growing season. To be safe most years, wait until Apr 6 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 10 | May 15 | Apr 26 |
| Freeze (32°F) | May 25 | Apr 29 | Apr 6 |
| Hard (28°F) | May 5 | Apr 13 | Mar 16 |
| Severe (24°F) | Apr 21 | Mar 26 | Feb 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 10 | Jun 4 | May 30 | May 22 | May 15 | May 10 | May 5 | Apr 30 | Apr 26 |
| 32°F | May 25 | May 13 | May 6 | May 2 | Apr 29 | Apr 25 | Apr 20 | Apr 15 | Apr 6 |
| 28°F | May 5 | Apr 28 | Apr 23 | Apr 18 | Apr 13 | Apr 8 | Apr 2 | Mar 28 | Mar 16 |
| 24°F | Apr 21 | Apr 13 | Apr 6 | Mar 31 | Mar 26 | Mar 18 | Mar 11 | Mar 6 | Feb 28 |
| 20°F | Apr 2 | Mar 24 | Mar 14 | Mar 8 | Mar 4 | Feb 28 | Feb 25 | Feb 21 | Feb 14 |
| 16°F | Mar 11 | Mar 2 | Feb 26 | Feb 22 | Feb 18 | Feb 14 | Feb 9 | Feb 5 | Jan 30 |
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 24 | Oct 7 | Oct 23 |
| Freeze (32°F) | Oct 1 | Oct 20 | Nov 5 |
| Hard (28°F) | Oct 18 | Nov 2 | Nov 15 |
| Severe (24°F) | Oct 28 | Nov 12 | Nov 25 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 24 | Sep 28 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 15 | Oct 19 | Oct 23 |
| 32°F | Oct 1 | Oct 7 | Oct 12 | Oct 16 | Oct 20 | Oct 24 | Oct 27 | Oct 31 | Nov 5 |
| 28°F | Oct 18 | Oct 23 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 |
| 24°F | Oct 28 | Nov 2 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 25 |
| 20°F | Nov 6 | Nov 11 | Nov 15 | Nov 18 | Nov 21 | Nov 23 | Nov 26 | Nov 28 | Dec 4 |
| 16°F | Nov 13 | Nov 19 | Nov 22 | Nov 26 | Nov 28 | Dec 1 | Dec 4 | Dec 8 | Dec 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: Weber Basin Pump Plt 3, Ut, about 3.6 miles away@if(!empty($station['elevation_ft'])), at 4,900 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 South Ogden, UT?
On average, the last spring frost (32°F) around South Ogden, UT is about Apr 29. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 6.
When is the first frost in the fall?
The first fall frost around South Ogden, UT typically arrives about Oct 20. 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 29 on average, or Apr 6 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 172 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 84405 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026