USDA Hardiness Zone 7a
Frost Dates for 86556 — Tsaile, Arizona
NOAA 1991–2020 normals from Lukachukai, AZ (6,520 ft), 11 miles north.
Updated
In Tsaile, the last spring frost (32°F) is around May 3 in half of years and has passed by May 22 in nine years out of ten. The first fall frost comes around October 17, as early as October 2 one year in ten, leaving a typical freeze-free season of 163 days (NOAA, Lukachukai, AZ).
- Last spring frost
- May 3
- First fall frost
- October 17
- Growing season
- 163 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
- December 6
- Last snow
- February 28
- Winters with snow
- 90%
- Snow per year
- 4.9"
median, 1991–2020
median, 1991–2020
26 of 29 observed
NOAA normal
Frost risk by date in Tsaile
Half of springs at Lukachukai, AZ see their last 32°F night by May 3; only one in ten is past it by April 21, and one in ten still has one after May 22. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 14 20%, and after May 22 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 October 17 in half of years, as early as October 2 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 10 days later, around October 27; in spring the one-in-ten date for 28°F is May 9, 13 days before the 32°F one. The freeze-free season lasts 163 days in a typical year, shorter than at 82% of the 98 Arizona stations; it reaches 185 days one year in ten and falls short of 143 one year in ten. On average 146 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 13 days longer, to about May 16, and return around October 8. Severe cold of 16°F or below comes every winter, usually between November 25 and February 27.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | May 5 | May 9 | May 13 | May 16 | May 20 | May 24 | May 29 | Jun 6 |
| 32°F | Apr 21 | Apr 25 | Apr 28 | Apr 30 | May 3 | May 7 | May 10 | May 14 | May 22 |
| 28°F | Apr 8 | Apr 13 | Apr 17 | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 3 | May 9 |
| 24°F | Mar 16 | Mar 29 | Apr 2 | Apr 6 | Apr 9 | Apr 12 | Apr 15 | Apr 21 | Apr 28 |
| 20°F | Feb 21 | Feb 28 | Mar 4 | Mar 8 | Mar 13 | Mar 18 | Mar 25 | Apr 1 | Apr 8 |
| 16°F | Feb 5 | Feb 12 | Feb 17 | Feb 22 | Feb 27 | Mar 2 | Mar 6 | Mar 11 | Mar 20 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 24 | Sep 29 | Oct 3 | Oct 5 | Oct 8 | Oct 10 | Oct 13 | Oct 16 | Oct 20 |
| 32°F | Oct 2 | Oct 7 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 26 | Oct 30 |
| 28°F | Oct 11 | Oct 16 | Oct 20 | Oct 23 | Oct 27 | Oct 30 | Nov 2 | Nov 6 | Nov 12 |
| 24°F | Oct 20 | Oct 26 | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 16 | Nov 20 |
| 20°F | Oct 27 | Nov 2 | Nov 7 | Nov 12 | Nov 16 | Nov 19 | Nov 21 | Nov 25 | Nov 30 |
| 16°F | Nov 5 | Nov 14 | Nov 19 | Nov 22 | Nov 25 | Nov 28 | Dec 1 | Dec 5 | Dec 11 |
Freeze probabilities 1991–2020 at Lukachukai, 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 86556 →Compare Tsaile with another place →
Weather by month in Tsaile
July is the warmest month at Lukachukai, AZ, averaging 88°F by day and 59°F at night; January is the coldest at 39°F and 18°F. A freezing night is all but certain in every month from October 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 57% of years.
Warmth for growing adds up to 2,881 growing degree days a year (base 50°F), fewer than at 86% of the 102 Arizona stations. 31% of them (880) have built up by the end of June, and July adds the most, 717.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 39 | 18 | 100% | 29 | 0 |
| Feb | 46 | 24 | 100% | 24 | 0 |
| Mar | 55 | 30 | 100% | 21 | 12 |
| Apr | 60 | 35 | 100% | 13 | 61 |
| May | 72 | 43 | 57% | 3 | 256 |
| Jun | 84 | 53 | 1% | 0 | 551 |
| Jul | 88 | 59 | 0% | 0 | 717 |
| Aug | 85 | 58 | 0% | 0 | 662 |
| Sep | 79 | 52 | 7% | 1 | 465 |
| Oct | 67 | 39 | 91% | 6 | 143 |
| Nov | 53 | 29 | 100% | 20 | 14 |
| Dec | 41 | 19 | 100% | 29 | 0 |
Monthly normals 1991–2020 at Lukachukai, AZ (6,520 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, Canyon De Chelly, AZ, 22 miles west of Tsaile and 910 feet lower, has a last frost 3 days later (May 6), a first frost 9 days earlier (October 8), a season 10 days shorter.
When it snows in Tsaile, Arizona
The first measurable snow (0.1 inch or more) in Tsaile usually arrives around December 6, and the last of the season around February 28. Those are the middle dates across the winters of 1991–2020 at Canyon De Chelly, AZ, 21.9 miles away: half of years saw snow earlier, half later. Snow fell in 90% of those winters. The last 32°F night of spring typically comes 64 days after the last snow.
Planting calendar for 86556
| When | What to do |
|---|---|
| February 22 – March 8 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 8 – March 22 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 5 – April 19 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 3 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 25 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 3 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 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 86556 is 11 miles from Lukachukai, AZ, which stands at 6,520 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 86556 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.