USDA Hardiness Zone 6a
Frost Dates for 84634 — Gunnison, Utah
NOAA 1991–2020 normals from Manti Radio Kmti, UT (5,498 ft), 12 miles northeast.
Updated
In Gunnison, the last spring frost (32°F) is around May 31 in half of years and has passed by June 16 in nine years out of ten. The first fall frost comes around September 21, as early as September 8 one year in ten, leaving a typical freeze-free season of 114 days (NOAA, Manti Radio Kmti, UT).
- Last spring frost
- May 31
- First fall frost
- September 21
- Growing season
- 114 days
- Hardiness zone
- 6a
50% probability
50% probability
freeze-free, 50%
-10 to -5°F (-23.3 to -20.6°C) coldest night
- First snow
- November 4
- Last snow
- April 19
- Winters with snow
- 100%
- Snow per year
- 52.9"
median, 1991–2020
median, 1991–2020
27 of 27 observed
NOAA normal
Frost risk by date in Gunnison
Half of springs at Manti Radio Kmti, UT see their last 32°F night by May 31; only one in ten is past it by May 12, and one in ten still has one after June 16. Planting tender crops after June 5 leaves a 30% risk of a frost on them, after June 10 20%, and after June 16 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 83% of the 66 Utah stations behind this site's ZIP pages.
In fall the first 32°F night comes by September 21 in half of years, as early as September 8 one year in ten, and holds off past October 2 one year in ten. A hard freeze of 28°F follows 8 days later, around September 29; in spring the one-in-ten date for 28°F is June 3, 13 days before the 32°F one. The freeze-free season lasts 114 days in a typical year, shorter than at 83% of the 66 Utah stations; it reaches 134 days one year in ten and falls short of 93 one year in ten. On average 198 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 June 14, and return around September 12. Severe cold of 16°F or below comes every winter, usually between November 4 and March 17.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 31 | Jun 4 | Jun 8 | Jun 11 | Jun 14 | Jun 17 | Jun 20 | Jun 24 | Jun 29 |
| 32°F | May 12 | May 18 | May 22 | May 28 | May 31 | Jun 2 | Jun 5 | Jun 10 | Jun 16 |
| 28°F | Apr 27 | May 1 | May 5 | May 8 | May 11 | May 15 | May 20 | May 26 | Jun 3 |
| 24°F | Apr 11 | Apr 17 | Apr 21 | Apr 24 | Apr 28 | May 1 | May 4 | May 8 | May 12 |
| 20°F | Mar 19 | Mar 28 | Apr 2 | Apr 6 | Apr 10 | Apr 14 | Apr 18 | Apr 23 | Apr 30 |
| 16°F | Feb 24 | Mar 3 | Mar 8 | Mar 13 | Mar 17 | Mar 23 | Mar 29 | Apr 3 | Apr 12 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Aug 30 | Sep 3 | Sep 6 | Sep 9 | Sep 12 | Sep 14 | Sep 17 | Sep 20 | Sep 24 |
| 32°F | Sep 8 | Sep 12 | Sep 16 | Sep 19 | Sep 21 | Sep 23 | Sep 25 | Sep 28 | Oct 2 |
| 28°F | Sep 17 | Sep 21 | Sep 25 | Sep 27 | Sep 29 | Oct 2 | Oct 6 | Oct 9 | Oct 15 |
| 24°F | Sep 27 | Oct 1 | Oct 5 | Oct 8 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 27 |
| 20°F | Oct 8 | Oct 13 | Oct 17 | Oct 21 | Oct 24 | Oct 27 | Oct 31 | Nov 3 | Nov 8 |
| 16°F | Oct 18 | Oct 23 | Oct 28 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 15 | Nov 19 |
Freeze probabilities 1991–2020 at Manti Radio Kmti, 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 84634 →Compare Gunnison with another place →
Compared with the next station
The nearest other station, Manti, UT, 13 miles east of Gunnison and 242 feet higher, has a last frost 20 days earlier (May 11), a first frost 15 days later (October 6), a season 32 days longer.
When it snows in Gunnison, Utah
The first measurable snow (0.1 inch or more) in Gunnison usually arrives around November 4, and the last of the season around April 19. Those are the middle dates across the winters of 1991–2020 at Manti, UT, 12.6 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 42 days after the last snow.
Planting calendar for 84634
| When | What to do |
|---|---|
| March 22 – April 5 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| April 5 – April 19 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| May 3 – May 17 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 31 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by June 29 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 7 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| September 21 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 84634 is 12 miles from Manti Radio Kmti, UT, which stands at 5,498 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 84634 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°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.