USDA Hardiness Zone 7b
Frost Dates for 84119 — West Valley City, Utah
NOAA 1991–2020 normals from Salt Lake City International Airport, UT (4,225 ft), 6 miles north.
Updated
In West Valley City, the last spring frost (32°F) is around April 8 in half of years and has passed by April 30 in nine years out of ten. The first fall frost comes around October 31, as early as October 17 one year in ten, leaving a typical freeze-free season of 204 days (NOAA, Salt Lake City International Airport, UT).
- Last spring frost
- April 8
- First fall frost
- October 31
- Growing season
- 204 days
- Hardiness zone
- 7b
50% probability
50% probability
freeze-free, 50%
5 to 10°F (-15.0 to -12.2°C) coldest night
- First snow
- November 6
- Last snow
- April 15
- Winters with snow
- 100%
- Snow per year
- 51.9"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in West Valley City
Half of springs at Salt Lake City International Airport, UT see their last 32°F night by April 8; only one in ten is past it by March 17, and one in ten still has one after April 30. Planting tender crops after April 16 leaves a 30% risk of a frost on them, after April 21 20%, and after April 30 10%. The 22 days between the even-odds date and the one-in-ten date is wider than at 80% of the 66 Utah stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.
In fall the first 32°F night comes by October 31 in half of years, as early as October 17 one year in ten, and holds off past November 13 one year in ten. A hard freeze of 28°F follows 10 days later, around November 10; in spring the one-in-ten date for 28°F is April 8, 22 days before the 32°F one. The freeze-free season lasts 204 days in a typical year, longer than at 94% of the 66 Utah stations; it reaches 229 days one year in ten and falls short of 177 one year in ten. On average 112 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 19 days longer, to about April 27, and return around October 19. Severe cold of 16°F or below comes in 98% of winters, usually between December 11 and February 5.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 8 | Apr 14 | Apr 18 | Apr 22 | Apr 27 | Apr 30 | May 3 | May 8 | May 14 |
| 32°F | Mar 17 | Mar 27 | Mar 31 | Apr 4 | Apr 8 | Apr 11 | Apr 16 | Apr 21 | Apr 30 |
| 28°F | Feb 27 | Mar 4 | Mar 7 | Mar 11 | Mar 15 | Mar 20 | Mar 27 | Mar 31 | Apr 8 |
| 24°F | Feb 8 | Feb 15 | Feb 20 | Feb 25 | Feb 28 | Mar 2 | Mar 7 | Mar 11 | Mar 19 |
| 20°F | Jan 27 | Feb 3 | Feb 7 | Feb 12 | Feb 16 | Feb 20 | Feb 24 | Feb 28 | Mar 4 |
| 16°F98% of yrs | Jan 5 | Jan 16 | Jan 26 | Feb 1 | Feb 5 | Feb 9 | Feb 13 | Feb 18 | Feb 24 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 7 | Oct 11 | Oct 15 | Oct 17 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 2 |
| 32°F | Oct 17 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 9 | Nov 13 |
| 28°F | Oct 27 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 20 | Nov 24 |
| 24°F | Nov 5 | Nov 10 | Nov 14 | Nov 18 | Nov 21 | Nov 24 | Nov 27 | Dec 1 | Dec 6 |
| 20°F | Nov 13 | Nov 20 | Nov 23 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 14 | Dec 20 |
| 16°F98% of yrs | Nov 22 | Nov 28 | Dec 1 | Dec 6 | Dec 11 | Dec 16 | Dec 21 | Dec 27 | Jan 4 |
Freeze probabilities 1991–2020 at Salt Lake City International Airport, 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 84119 →Compare West Valley City with another place →
Weather by month in West Valley City
July is the warmest month at Salt Lake City International Airport, UT, averaging 94°F by day and 68°F at night; January is the coldest at 39°F and 24°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 65% of years.
Warmth for growing adds up to 3,827 growing degree days a year (base 50°F), more than at 91% of the 66 Utah stations. 31% of them (1,188) have built up by the end of June, and July adds the most, 964. Precipitation totals 15.7 inches a year, most in April (2.2") and least in July (0.5"); May to September bring 32% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 39 | 24 | 1.4 | 100% | 27 | 1 |
| Feb | 45 | 29 | 1.3 | 100% | 21 | 4 |
| Mar | 55 | 36 | 1.8 | 99% | 12 | 43 |
| Apr | 62 | 42 | 2.2 | 65% | 4 | 127 |
| May | 73 | 50 | 1.8 | 10% | <1 | 366 |
| Jun | 84 | 59 | 1.0 | 0% | 0 | 648 |
| Jul | 94 | 68 | 0.5 | 0% | 0 | 964 |
| Aug | 92 | 67 | 0.6 | 0% | 0 | 904 |
| Sep | 81 | 56 | 1.1 | 0% | 0 | 555 |
| Oct | 66 | 44 | 1.3 | 52% | 3 | 190 |
| Nov | 51 | 33 | 1.3 | 100% | 17 | 25 |
| Dec | 39 | 25 | 1.4 | 100% | 27 | 2 |
Monthly normals 1991–2020 at Salt Lake City International Airport, UT (4,225 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, Salt Lake Triad Ctr, UT, 6 miles northeast of West Valley City, has a last frost 8 days earlier (March 31), a first frost 8 days later (November 8), a season 20 days longer.
When it snows in West Valley City, Utah
The first measurable snow (0.1 inch or more) in West Valley City usually arrives around November 6, and the last of the season around April 15. Those are the middle dates across the winters of 1991–2020 at Salt Lake City International Airport, UT, 5.7 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 7 days before the last snow.
Planting calendar for 84119
| When | What to do |
|---|---|
| January 28 – February 11 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 11 – February 25 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 11 – March 25 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 8 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 8 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 17 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 31 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 84119 is 6 miles from Salt Lake City International Airport, UT, which stands at 4,225 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 84119 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°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.