Williams, Arizona climate: Normal weather by month, frost dates and records
Williams's normal year runs from 21°F December nights to 84°F July afternoons, with 21.6 inches of precipitation and 65 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.1°C, December lows of −6°C, July highs of 29°C, 549 mm of precipitation a year.
- NOAA stationWilliams
- Station IDUSC00029359
- Location35.24°N 112.19°W
- Elevation6,909 ft (2,106 m)
- Population3,482
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Williams.
- Jan 47° 21°
- Feb 49° 23°
- Mar 56° 27°
- Apr 62° 31°
- May 71° 39°
- Jun 82° 48°
- Jul 84° 54°
- Aug 82° 52°
- Sep 76° 47°
- Oct 67° 36°
- Nov 56° 28°
- Dec 47° 21°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Williams each month?
July is the warmest month, with normal highs of 84°F; December the coldest, with normal lows of 21°F. The most precipitation falls in August (3.38 in), the least in June (0.38 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 47°F | 21°F | 34.3°F | 2.17 | 16.8 | 7 | <1 | 28 | 10 h |
| February | 49°F | 23°F | 35.9°F | 2.61 | 12.4 | 6 | <1 | 24 | 10 h 50 min |
| March | 56°F | 27°F | 41.2°F | 2.00 | 11.1 | 6 | <1 | 23 | 11 h 50 min |
| April | 62°F | 31°F | 46.8°F | 0.87 | 5.7 | 4 | <1 | 15 | 13 h |
| May | 71°F | 39°F | 55.1°F | 0.76 | 0.1 | 4 | <1 | 5 | 14 h |
| June | 82°F | 48°F | 64.9°F | 0.38 | 0.0 | 3 | 2 | <1 | 14 h 30 min |
| July | 84°F | 54°F | 68.8°F | 2.98 | 0.0 | 11 | 4 | <1 | 14 h 20 min |
| August | 82°F | 52°F | 66.9°F | 3.38 | 0.0 | 13 | 2 | <1 | 13 h 30 min |
| September | 76°F | 47°F | 61.5°F | 1.59 | 0.0 | 7 | <1 | 1 | 12 h 30 min |
| October | 67°F | 36°F | 51.3°F | 1.59 | 0.7 | 4 | <1 | 7 | 11 h 20 min |
| November | 56°F | 28°F | 41.7°F | 1.34 | 4.8 | 4 | <1 | 20 | 10 h 20 min |
| December | 47°F | 21°F | 33.9°F | 1.94 | 13.5 | 6 | <1 | 28 | 9 h 50 min |
| Year (annual) | 65°F | 36°F | 50.2°F | 21.61 | 65.1 | 73 | 8 | 150 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 8°C | −6°C | 1.3°C | 55 mm | 43 cm |
| February | 10°C | −5°C | 2.2°C | 66 mm | 31 cm |
| March | 13°C | −3°C | 5.1°C | 51 mm | 28 cm |
| April | 17°C | 0°C | 8.2°C | 22 mm | 14 cm |
| May | 22°C | 4°C | 12.8°C | 19 mm | 0 cm |
| June | 28°C | 9°C | 18.3°C | 10 mm | 0 cm |
| July | 29°C | 12°C | 20.4°C | 76 mm | 0 cm |
| August | 28°C | 11°C | 19.4°C | 86 mm | 0 cm |
| September | 25°C | 8°C | 16.4°C | 40 mm | 0 cm |
| October | 19°C | 2°C | 10.7°C | 40 mm | 2 cm |
| November | 13°C | −2°C | 5.4°C | 34 mm | 12 cm |
| December | 8°C | −6°C | 1.1°C | 49 mm | 34 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00029359; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Williams?
Normal highs sit between 65°F and 85°F in May, June, July, August, September and October. Of those, June has the fewest days with rain (3).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00029359.
When is the last frost in Williams?
In Williams, the last spring frost (32°F) comes after May 22 in half of years and after June 10 in one year in ten; the first autumn frost comes before October 5 in half of years and before September 24 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 221 year in 10 after June 10; 9 in 10 after May 6
- First autumn frost, half of years before
- October 51 year in 10 before September 24; 9 in 10 before October 18
NOAA puts the median frost-free season at 135 days, and the season without a hard freeze (28°F) at 159 days.
A hard freeze (28°F) comes after May 9 in half of springs and before October 15 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Williams in zone 6b in ZIP code 86018, the nearest ZIP area.
Frost dates for every NOAA station in Arizona · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00029359; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Williams?
In a normal year in Williams, 8 days a year reach 90°F, 150 nights fall to 32°F or colder and 73 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 150a normal year
- Days that stay below freezing
- 5high of 32°F or less
- Days with 0.01 inch of precipitation
- 73a normal year
- Days with 1 inch of snow or more
- 16a normal year
The highest temperature in this station's record (since 1897) is 102°F, on July 1, 1909; the lowest is −25°F, on January 22, 1937.
The wettest calendar year on that record is 1965, with 39.93 in; the snowiest season is 2022–23, with 139.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00029359; records: ACIS (NOAA Regional Climate Centers), station USC00029359. Records use complete months only; a month missing more than three days is left out.
How sunny is Williams?
Over a year 86% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Williams, 5.5 kWh per square metre a day. June is the sunniest month (93%) and December the cloudiest (80%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 82% | 3.2 |
| February | 82% | 4.1 |
| March | 86% | 5.6 |
| April | 88% | 7.0 |
| May | 89% | 7.8 |
| June | 93% | 8.4 |
| July | 81% | 6.8 |
| August | 84% | 6.5 |
| September | 89% | 6.0 |
| October | 89% | 4.8 |
| November | 88% | 3.6 |
| December | 80% | 2.8 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Williams need?
A normal year in Williams brings 5,671 heating degree days, 6% more than the median U.S. place (5,373), and 298 cooling degree days, 67% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,269 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 952 | 0 |
| February | 813 | 0 |
| March | 738 | 0 |
| April | 546 | 0 |
| May | 312 | 6 |
| June | 69 | 64 |
| July | 9 | 128 |
| August | 22 | 80 |
| September | 123 | 18 |
| October | 423 | 0 |
| November | 701 | 0 |
| December | 964 | 0 |
| Year (annual) | 5,671 | 298 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00029359. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Williams been warmer than normal lately?
2023 averaged 50.2°F, equal to the 1991-2020 normal of 50.2°F. 1 of the 2 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 50.4°F | +0.2°F | 19.56 | 44.6 |
| 2023 | 50.2°F | at normal | 18.94 | 128.9 |
Source: observed years: ACIS, station USC00029359. A year counts only with all twelve months complete.
How does Williams's climate compare?
Williams is warmer than 8 of the other 96 places with their own NOAA record in Arizona, and wetter than 84. Across the 7,247 U.S. stations with normals, its annual mean of 50.2°F is warmer than 41%.
In the Köppen classification computed from these normals, Williams is Csb: temperate, dry-summer, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Williams share this climate record?
3 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Red Lake, AZ1,764 people · 8 mi N
- Kaibab Estates West, AZ1,406 people · 17 mi W
- Ash Fork, AZ578 people · 17 mi W
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Williams's climate
What is the coldest month in Williams?
December, with a normal high of 47°F and a normal low of 21°F. The warmest is July (84°F by day, 54°F at night).
Does it snow in Williams?
Yes: 65 inches in a normal year, falling on 18 days with 0.1 inch or more, the most in January (16.8 inches).
What is the rainiest month in Williams?
August, with 3.38 in of precipitation in a normal year; the driest is June with 0.38 in.
What plant hardiness zone is Williams in?
The USDA's 2023 map puts Williams in zone 6b in ZIP code 86018, the nearest ZIP area.
How late can frost come in Williams?
In half of years the last 32°F night comes after May 22; in one year in ten it comes after June 10. Waiting until June 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Arizona climateThe statewide normals and every place in the state
- Bellemont, AZ21 miles from this station, 44.4°F a year
- Fort Valley, AZ25 miles from this station, 47.4°F a year
- Flagstaff, AZ30 miles from this station, 46.8°F a year
- Oak Creek Canyon, AZ32 miles from this station, 57.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made