USDA Hardiness Zone 9a
Frost Dates for 85324 — Black Canyon City, Arizona
NOAA 1991–2020 normals from Cordes, AZ (3,771 ft), 14 miles north.
Updated
In Black Canyon City, the last spring frost (32°F) is around April 5 in half of years and has passed by April 24 in nine years out of ten. The first fall frost comes around November 17, as early as October 28 one year in ten, leaving a typical freeze-free season of 221 days (NOAA, Cordes, AZ).
- Last spring frost
- April 5
- First fall frost
- November 17
- Growing season
- 221 days
- Hardiness zone
- 9a
50% probability
50% probability
freeze-free, 50%
20 to 25°F (-6.7 to -3.9°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 32%
- Snow per year
- 1.2"
median, 1991–2020
median, 1991–2020
9 of 28 observed
NOAA normal
Frost risk by date in Black Canyon City
Half of springs at Cordes, AZ see their last 32°F night by April 5; only one in ten is past it by March 9, and one in ten still has one after April 24. Planting tender crops after April 12 leaves a 30% risk of a frost on them, after April 17 20%, and after April 24 10%. The 19 days between the even-odds date and the one-in-ten date is narrower than at 61% of the 98 Arizona stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 17 in half of years, as early as October 28 one year in ten, and holds off past December 3 one year in ten. A hard freeze of 28°F follows 11 days later, around November 28; in spring the one-in-ten date for 28°F is April 9, 15 days before the 32°F one. The freeze-free season lasts 221 days in a typical year, shorter than at 58% of the 98 Arizona stations; it reaches 253 days one year in ten and falls short of 195 one year in ten. On average 44 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 24, and return around November 4. Nights of 24°F, cold enough to damage hardier plants, come in 96% of winters and 16°F in 19%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 5 | Apr 11 | Apr 15 | Apr 20 | Apr 24 | Apr 27 | May 1 | May 6 | May 13 |
| 32°F | Mar 9 | Mar 18 | Mar 27 | Apr 1 | Apr 5 | Apr 9 | Apr 12 | Apr 17 | Apr 24 |
| 28°F | Feb 7 | Feb 18 | Feb 25 | Mar 2 | Mar 7 | Mar 13 | Mar 21 | Mar 31 | Apr 9 |
| 24°F96% of yrs | Dec 25 | Jan 8 | Jan 20 | Feb 1 | Feb 7 | Feb 13 | Feb 19 | Feb 26 | Mar 6 |
| 20°F59% of yrs | Dec 8 | Dec 16 | Dec 26 | Jan 3 | Jan 8 | Jan 25 | Feb 5 | Feb 13 | Feb 21 |
| 16°F19% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 19 | Oct 24 | Oct 29 | Nov 1 | Nov 4 | Nov 8 | Nov 11 | Nov 16 | Nov 21 |
| 32°F | Oct 28 | Nov 4 | Nov 9 | Nov 13 | Nov 17 | Nov 20 | Nov 23 | Nov 27 | Dec 3 |
| 28°F | Nov 9 | Nov 16 | Nov 21 | Nov 24 | Nov 28 | Dec 2 | Dec 6 | Dec 10 | Dec 17 |
| 24°F96% of yrs | Nov 21 | Nov 27 | Dec 2 | Dec 7 | Dec 11 | Dec 15 | Dec 21 | Dec 28 | Jan 9 |
| 20°F59% of yrs | Nov 30 | Dec 7 | Dec 13 | Dec 17 | Dec 26 | Jan 1 | Jan 7 | Jan 25 | Feb 9 |
| 16°F19% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Cordes, 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 85324 →Compare Black Canyon City with another place →
Weather by month in Black Canyon City
July is the warmest month at Cordes, AZ, averaging 96°F by day and 66°F at night; December is the coldest at 58°F and 33°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 90% of years and April still brings one in 60% of years.
Warmth for growing adds up to 4,943 growing degree days a year (base 50°F), fewer than at 63% of the 102 Arizona stations. 35% of them (1,716) have built up by the end of June, and July adds the most, 961. Precipitation totals 15.2 inches a year, most in August (2.1") and least in June (0.1"); May to September bring 41% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 59 | 34 | 1.7 | 100% | 12 | 28 |
| Feb | 61 | 35 | 1.9 | 100% | 8 | 44 |
| Mar | 67 | 38 | 1.4 | 90% | 4 | 126 |
| Apr | 74 | 42 | 0.4 | 60% | 2 | 251 |
| May | 83 | 50 | 0.4 | 3% | 0 | 502 |
| Jun | 93 | 58 | 0.1 | 0% | 0 | 766 |
| Jul | 96 | 66 | 2.0 | 0% | 0 | 961 |
| Aug | 94 | 66 | 2.1 | 0% | 0 | 928 |
| Sep | 89 | 60 | 1.6 | 0% | 0 | 730 |
| Oct | 79 | 49 | 1.1 | 15% | 1 | 433 |
| Nov | 67 | 39 | 1.0 | 82% | 4 | 148 |
| Dec | 58 | 33 | 1.5 | 100% | 13 | 26 |
Monthly normals 1991–2020 at Cordes, AZ (3,771 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, Carefree, AZ, 23 miles southeast of Black Canyon City and 1,241 feet lower, has a last frost 60 days earlier (February 4), a first frost 29 days later (December 16), a season 92 days longer.
When it snows in Black Canyon City, Arizona
Measurable snow is rare here: only 9 of 28 winters from 1991 to 2020 recorded 0.1 inch or more at Cordes, AZ, 14.1 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 85324
| When | What to do |
|---|---|
| January 25 – February 8 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 8 – February 22 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 8 – March 22 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 5 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 25 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 3 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 17 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 85324 is 14 miles from Cordes, AZ, which stands at 3,771 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 86333 (Mayer). The 2023 USDA Plant Hardiness Zone Map lists ZIP 85324 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°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.