USDA Hardiness Zone 8a
Frost Dates for 86323 — Chino Valley, Arizona
NOAA 1991–2020 normals from Chino Valley, AZ (4,750 ft), under a mile south.
Updated
In Chino Valley, the last spring frost (32°F) is around April 27 in half of years and has passed by May 18 in nine years out of ten. The first fall frost comes around October 24, as early as October 9 one year in ten, leaving a typical freeze-free season of 178 days (NOAA, Chino Valley, AZ).
- Last spring frost
- April 27
- First fall frost
- October 24
- Growing season
- 178 days
- Hardiness zone
- 8a
50% probability
50% probability
freeze-free, 50%
10 to 15°F (-12.2 to -9.4°C) coldest night
- First snow
- December 20
- Last snow
- March 9
- Winters with snow
- 97%
- Snow per year
- 10.2"
median, 1991–2020
median, 1991–2020
29 of 30 observed
NOAA normal
Frost risk by date in Chino Valley
Half of springs at Chino Valley, AZ see their last 32°F night by April 27; only one in ten is past it by April 10, and one in ten still has one after May 18. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 10 20%, and after May 18 10%. The 21 days between the even-odds date and the one-in-ten date is narrower than at 47% of the 98 Arizona 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 24 in half of years, as early as October 9 one year in ten, and holds off past November 8 one year in ten. A hard freeze of 28°F follows 12 days later, around November 5; in spring the one-in-ten date for 28°F is April 29, 19 days before the 32°F one. The freeze-free season lasts 178 days in a typical year, shorter than at 77% of the 98 Arizona stations; it reaches 199 days one year in ten and falls short of 155 one year in ten. On average 127 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 16 days longer, to about May 13, and return around October 12. Severe cold of 16°F or below comes in 98% of winters, usually between December 12 and January 30.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 26 | May 1 | May 5 | May 9 | May 13 | May 17 | May 22 | May 28 | Jun 2 |
| 32°F | Apr 10 | Apr 15 | Apr 20 | Apr 24 | Apr 27 | May 1 | May 4 | May 10 | May 18 |
| 28°F | Mar 18 | Mar 26 | Mar 31 | Apr 5 | Apr 9 | Apr 13 | Apr 17 | Apr 23 | Apr 29 |
| 24°F | Feb 23 | Mar 2 | Mar 7 | Mar 11 | Mar 16 | Mar 22 | Mar 29 | Apr 5 | Apr 11 |
| 20°F | Jan 25 | Feb 4 | Feb 10 | Feb 16 | Feb 23 | Feb 28 | Mar 3 | Mar 8 | Mar 17 |
| 16°F98% of yrs | Dec 31 | Jan 6 | Jan 14 | Jan 22 | Jan 30 | Feb 4 | Feb 11 | Feb 21 | Mar 1 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 12 | Oct 14 | Oct 18 | Oct 21 | Oct 27 |
| 32°F | Oct 9 | Oct 13 | Oct 17 | Oct 20 | Oct 24 | Oct 27 | Oct 31 | Nov 3 | Nov 8 |
| 28°F | Oct 18 | Oct 25 | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 19 |
| 24°F | Oct 30 | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 24 | Nov 28 |
| 20°F | Nov 10 | Nov 17 | Nov 20 | Nov 23 | Nov 26 | Nov 29 | Dec 2 | Dec 7 | Dec 14 |
| 16°F98% of yrs | Nov 22 | Nov 28 | Dec 1 | Dec 6 | Dec 12 | Dec 17 | Dec 22 | Dec 29 | Jan 7 |
Freeze probabilities 1991–2020 at Chino Valley, AZ, 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 86323 →Compare Chino Valley with another place →
Weather by month in Chino Valley
July is the warmest month at Chino Valley, AZ, averaging 93°F by day and 62°F at night; December is the coldest at 53°F and 24°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 40% of years.
Warmth for growing adds up to 3,830 growing degree days a year (base 50°F), fewer than at 75% of the 102 Arizona stations. 34% of them (1,287) have built up by the end of June, and July adds the most, 865.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 54 | 24 | 100% | 28 | 1 |
| Feb | 57 | 27 | 100% | 23 | 7 |
| Mar | 65 | 32 | 100% | 17 | 55 |
| Apr | 71 | 37 | 96% | 7 | 159 |
| May | 80 | 45 | 40% | 1 | 398 |
| Jun | 91 | 54 | 2% | 0 | 668 |
| Jul | 93 | 62 | 0% | 0 | 865 |
| Aug | 91 | 60 | 0% | 0 | 795 |
| Sep | 86 | 53 | 0% | 0 | 579 |
| Oct | 76 | 41 | 71% | 3 | 263 |
| Nov | 63 | 30 | 100% | 20 | 40 |
| Dec | 53 | 24 | 100% | 29 | 1 |
Monthly normals 1991–2020 at Chino Valley, AZ (4,750 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, Prescott Love Field, AZ, 8 miles south of Chino Valley and 292 feet higher, has a last frost 7 days earlier (April 20), a first frost 3 days later (October 27), a season 10 days longer.
When it snows in Chino Valley, Arizona
The first measurable snow (0.1 inch or more) in Chino Valley usually arrives around December 20, and the last of the season around March 9. Those are the middle dates across the winters of 1991–2020 at Prescott, AZ, 13.6 miles away: half of years saw snow earlier, half later. Snow fell in 97% of those winters. The last 32°F night of spring typically comes 49 days after the last snow.
Planting calendar for 86323
| When | What to do |
|---|---|
| February 16 – March 2 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 2 – March 16 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 30 – April 13 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 27 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 1 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 10 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 24 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 86323 is under a mile from Chino Valley, AZ, which stands at 4,750 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 86305 (Prescott). The 2023 USDA Plant Hardiness Zone Map lists ZIP 86323 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°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.