USDA Hardiness Zone 7a
Frost Dates for 84096 — Herriman, Utah
NOAA 1991–2020 normals from Draper-Point Of Mountain, UT (4,506 ft), 9 miles east.
Updated
In Herriman, the last spring frost (32°F) is around April 18 in half of years and has passed by May 6 in nine years out of ten. The first fall frost comes around October 22, as early as October 7 one year in ten, leaving a typical freeze-free season of 185 days (NOAA, Draper-Point Of Mountain, UT).
- Last spring frost
- April 18
- First fall frost
- October 22
- Growing season
- 185 days
- Hardiness zone
- 7a
50% probability
50% probability
freeze-free, 50%
0 to 5°F (-17.8 to -15.0°C) coldest night
- First snow
- November 22
- Last snow
- April 3
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
17 of 17 observed
NOAA normal
Frost risk by date in Herriman
Half of springs at Draper-Point Of Mountain, UT see their last 32°F night by April 18; only one in ten is past it by March 31, and one in ten still has one after May 6. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 30 20%, and after May 6 10%. The 18 days between the even-odds date and the one-in-ten date is narrower than at 47% of the 66 Utah stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 22 in half of years, as early as October 7 one year in ten, and holds off past November 5 one year in ten. A hard freeze of 28°F follows 11 days later, around November 2; in spring the one-in-ten date for 28°F is April 17, 19 days before the 32°F one. The freeze-free season lasts 185 days in a typical year, longer than at 85% of the 66 Utah stations; it reaches 209 days one year in ten and falls short of 162 one year in ten. On average 116 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 14 days longer, to about May 2, and return around October 10. Severe cold of 16°F or below comes every winter, usually between December 4 and February 10.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 17 | Apr 22 | Apr 26 | Apr 30 | May 2 | May 5 | May 9 | May 14 | May 22 |
| 32°F | Mar 31 | Apr 5 | Apr 10 | Apr 14 | Apr 18 | Apr 22 | Apr 25 | Apr 30 | May 6 |
| 28°F | Mar 7 | Mar 14 | Mar 21 | Mar 28 | Mar 31 | Apr 3 | Apr 7 | Apr 12 | Apr 17 |
| 24°F | Feb 19 | Feb 26 | Mar 1 | Mar 4 | Mar 8 | Mar 12 | Mar 19 | Mar 27 | Apr 2 |
| 20°F | Feb 3 | Feb 9 | Feb 14 | Feb 18 | Feb 22 | Feb 26 | Mar 1 | Mar 5 | Mar 12 |
| 16°F | Jan 11 | Jan 24 | Feb 1 | Feb 6 | Feb 10 | Feb 14 | Feb 19 | Feb 24 | Mar 1 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 27 | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 13 | Oct 16 | Oct 19 | Oct 23 |
| 32°F | Oct 7 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Nov 1 | Nov 5 |
| 28°F | Oct 18 | Oct 22 | Oct 26 | Oct 29 | Nov 2 | Nov 5 | Nov 9 | Nov 13 | Nov 18 |
| 24°F | Oct 26 | Nov 1 | Nov 6 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 25 | Dec 1 |
| 20°F | Nov 6 | Nov 12 | Nov 16 | Nov 20 | Nov 24 | Nov 27 | Dec 1 | Dec 5 | Dec 12 |
| 16°F | Nov 14 | Nov 20 | Nov 26 | Nov 30 | Dec 4 | Dec 8 | Dec 14 | Dec 20 | Dec 29 |
Freeze probabilities 1991–2020 at Draper-Point Of Mountain, UT, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 84096 →Compare Herriman with another place →
Weather by month in Herriman
July is the warmest month at Draper-Point Of Mountain, UT, averaging 94°F by day and 66°F at night; January is the coldest at 40°F and 25°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 85% of years and May still brings one in 18% of years.
Warmth for growing adds up to 3,706 growing degree days a year (base 50°F), more than at 88% of the 66 Utah stations. 32% of them (1,178) have built up by the end of June, and July adds the most, 914.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 40 | 25 | 100% | 26 | 2 |
| Feb | 45 | 29 | 100% | 22 | 3 |
| Mar | 56 | 36 | 100% | 14 | 41 |
| Apr | 62 | 40 | 85% | 6 | 119 |
| May | 74 | 49 | 18% | 1 | 369 |
| Jun | 85 | 58 | 1% | <1 | 644 |
| Jul | 94 | 66 | 0% | 0 | 914 |
| Aug | 92 | 65 | 0% | 0 | 868 |
| Sep | 81 | 54 | 1% | 0 | 532 |
| Oct | 67 | 42 | 80% | 5 | 186 |
| Nov | 51 | 33 | 100% | 18 | 27 |
| Dec | 41 | 26 | 100% | 25 | 2 |
Monthly normals 1991–2020 at Draper-Point Of Mountain, UT (4,506 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Utah Lake Lehi, UT, 12 miles southeast of Herriman, has a last frost 12 days later (April 30), a first frost 13 days earlier (October 9), a season 26 days shorter.
When it snows in Herriman, Utah
The first measurable snow (0.1 inch or more) in Herriman usually arrives around November 22, and the last of the season around April 3. Those are the middle dates across the winters of 1991–2020 at Draper-Point Of Mountain, UT, 9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 15 days after the last snow.
Planting calendar for 84096
| When | What to do |
|---|---|
| February 7 – February 21 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 21 – March 7 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 21 – April 4 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 18 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 30 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 8 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 22 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 84096 is 9 miles from Draper-Point Of Mountain, UT, which stands at 4,506 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 84096 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.