Phoenix, AZ Climate & Monthly Averages
Phoenix has a semi-arid climate. July is the hottest month, averaging 106° by day; January is the coldest at 65°.
Phoenix's climate runs on sunshine and sparse rain
Phoenix works on a dry budget: 11.1 inches (282 mm) of precipitation a year, spread over roughly 34 days. Temperature does the varying instead, from 65°F (18°C) on a typical January afternoon to 106°F (41°C) in July, with nights 14°C below the day.
What the dry climate changes
Warmth peaks in July: highs of 106°F (41°C), lows of 84°F (29°C). January bottoms out at 65°F (18°C) in daylight, 42°F (6°C) after dark. Five of the twelve months pair mild highs with fewer than twelve wet days; the longest unbroken run is November through March.
Between the average July and the average January lie 24°C, a wider spread than roughly 77% of the cities we track. Precipitation concentrates in July - 1.9 inches (49 mm) on 5 days - and thins out by May. The gridded 2015-2024 daily record for this location tops out at 118°F (48°C) and bottoms at 28°F (-2°C) - decade extremes, not all-time station records.
More climate facts for Phoenix
- Hottest month: July - highs near 106°F (41°C)
- Coldest month: January - highs near 65°F (18°C)
- Decade extremes (2015-2024): 118°F (48°C) high · 28°F (-2°C) low
- Wettest month: July (5 rainy days) · Sunniest: June (13.2 h sun/day)
- Climate type: semi-arid
- Annual swing: 24°C between the average warmest and coolest month · day to night: 14°C
- Months averaging 30°C or hotter: 7
- Average humidity: 34%
Heat, cold and scarce precipitation in the dataset
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need another precipitation unit? Use the rainfall converter.
When the dry weather is easiest to use
Avoiding the hardest heat or cold
November to March is the sweet spot for Phoenix - temperatures sit either side of the peak heat rather than in it. Expect 71°F (22°C) in the afternoon and around 3 days of rain in a typical month of it. For the same question asked the other way round, see where else is warm in November.
Prepare for sun and cooler nights
Pack for Phoenix with lightweight, breathable clothing and serious sun protection. July nights average 84°F (29°C), so evenings rarely match the afternoons.
Monthly heat and rainfall table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 65° | 42° | 4 | 1.3 in | 8.5 h/day | 10.2 h | 14% | 55% |
| February | 70° | 45° | 3 | 1.2 in | 9.7 h/day | 10.9 h | 11% | 46% |
| March | 77° | 51° | 3 | 1.1 in | 10.6 h/day | 11.9 h | 10% | 37% |
| April | 87° | 59° | 1 | 0.2 in | 12.5 h/day | 13.0 h | 3% | 21% |
| May | 93° | 67° | 1 | 0.1 in | 12.9 h/day | 13.9 h | 3% | 19% |
| June | 105° | 78° | 1 | 0.2 in | 13.2 h/day | 14.4 h | 3% | 17% |
| July | 106° | 84° | 5 | 1.9 in | 12.1 h/day | 14.2 h | 16% | 31% |
| August | 104° | 83° | 5 | 1.4 in | 12.2 h/day | 13.4 h | 15% | 35% |
| September | 100° | 76° | 3 | 0.9 in | 11.4 h/day | 12.3 h | 9% | 33% |
| October | 89° | 64° | 2 | 1.0 in | 10.5 h/day | 11.3 h | 7% | 32% |
| November | 76° | 51° | 2 | 0.6 in | 9.4 h/day | 10.4 h | 5% | 36% |
| December | 66° | 44° | 4 | 1.3 in | 8.2 h/day | 9.9 h | 13% | 50% |
How daytime heat and cool nights change by month
Each card shows the average high and low. The bar places that month between Phoenix's coldest night and warmest afternoon.
January
- Rain
- 4 days
- Sunshine
- 8.5 h
- Daylight
- 10.2 h
February
- Rain
- 3 days
- Sunshine
- 9.7 h
- Daylight
- 10.9 h
March
- Rain
- 3 days
- Sunshine
- 10.6 h
- Daylight
- 11.9 h
April
- Rain
- 1 day
- Sunshine
- 12.5 h
- Daylight
- 13.0 h
May
- Rain
- 1 day
- Sunshine
- 12.9 h
- Daylight
- 13.9 h
June
- Rain
- 1 day
- Sunshine
- 13.2 h
- Daylight
- 14.4 h
July
- Rain
- 5 days
- Sunshine
- 12.1 h
- Daylight
- 14.2 h
August
- Rain
- 5 days
- Sunshine
- 12.2 h
- Daylight
- 13.4 h
September
- Rain
- 3 days
- Sunshine
- 11.4 h
- Daylight
- 12.3 h
October
- Rain
- 2 days
- Sunshine
- 10.5 h
- Daylight
- 11.3 h
November
- Rain
- 2 days
- Sunshine
- 9.4 h
- Daylight
- 10.4 h
December
- Rain
- 4 days
- Sunshine
- 8.2 h
- Daylight
- 9.9 h
Looking for warmer alternatives? Browse warm places by month, or compare Phoenix's coolest part of the year: January, December, February.
Heat and cold across the Phoenix year
Spring (March through May)
Spring brings hot afternoons here - highs near 86°F (30°C), nights near 59°F (15°C), and precipitation is sparse, near 1.3 inches (34 mm) for the season. Daylight is generous - around 12.0 hours of sun a day.
Summer (June through August)
Summer brings serious heat here - highs near 105°F (41°C), nights near 82°F (28°C), and rain comes on about 11 days over the three months. Daylight is generous - around 12.5 hours of sun a day.
Fall (September through November)
Through fall, Phoenix sits firmly in the heat: 88°F (31°C) by day, 64°F (18°C) after dark, and precipitation is sparse, near 2.5 inches (63 mm) for the season. Daylight is generous - around 10.4 hours of sun a day.
Winter (December through February)
Winter in Phoenix is crisp but comfortable, with daytime highs averaging 67°F (20°C) and nights around 44°F (6°C); rain comes on about 11 days over the three months.
How unusual is Phoenix?
- Relative humidity averages 34% - drier than almost every other city we track.
- Afternoons run 14°C above the following night - a bigger day-to-night gap than 97% of the 3496 cities we track.
- Rain or snow reaches the ground on 34 days a year - fewer wet days than all but 5% of the 3496 cities we track.
These comparisons use the same ten-year window for every city in the dataset.