Phoenix climate
Phoenix (Arizona, United States) has a hot desert climate (Köppen BWh). The average temperature over the year is 23 °C74 °F, and about 256 mm10 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Phoenix climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 1967 | 642 | 1254 | 331.3 | 2 |
| Feb | 2170 | 744 | 1457 | 321.3 | 1 |
| Mar | 2678 | 1050 | 1864 | 210.8 | 0 |
| Apr | 3086 | 1356 | 2271 | 80.3 | 0 |
| May | 3596 | 1865 | 2781 | 60.2 | 0 |
| Jun | 42107 | 2476 | 3391 | 20.1 | 0 |
| Jul | 42107 | 2883 | 3595 | 331.3 | 0 |
| Aug | 41105 | 2781 | 3493 | 331.3 | 0 |
| Sep | 38101 | 2475 | 3188 | 220.9 | 0 |
| Oct | 3290 | 1763 | 2476 | 140.6 | 0 |
| Nov | 2577 | 1151 | 1864 | 190.8 | 0 |
| Dec | 1966 | 542 | 1254 | 311.2 | 2 |
| Year | 42107 | 542 | 2374 | 25610 | 6 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 46% | 40% | 3.4 | 10:10 |
| Feb | 44% | 40% | 4.4 | 10:57 |
| Mar | 38% | 34% | 5.9 | 11:53 |
| Apr | 29% | 28% | 7.3 | 12:58 |
| May | 22% | 22% | 8.2 | 13:53 |
| Jun | 15% | 17% | 8.5 | 14:21 |
| Jul | 30% | 43% | 7.5 | 14:10 |
| Aug | 35% | 38% | 6.9 | 13:23 |
| Sep | 31% | 25% | 6.2 | 12:20 |
| Oct | 30% | 24% | 5.0 | 11:17 |
| Nov | 34% | 32% | 3.8 | 10:23 |
| Dec | 45% | 41% | 3.1 | 9:57 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Phoenix is like
The warmest month is July, with an average high of 42 °C107 °F and a low of 28 °C83 °F. The coldest is December, when highs average 19 °C66 °F and lows 5 °C42 °F. Seasons are strongly marked: the warmest month is on average 22.9 °C41.3 °F warmer than the coldest.
It is dry, with about 256 mm10 in of precipitation per year. The wettest three-month stretch is December–February, which brings 38% of the annual total. Months with less than 20 mm0.8 in on average: April–June and October and November. The wettest month is August (33 mm1.3 in), the driest is June (2 mm0.1 in).
Relative humidity ranges from 15% in June to 46% in January. The clearest skies (lowest average cloud amount, 17%) are typical of June. Average wind speed near the ground ranges from 6 km/h (4 mph) in August to 8 km/h (5 mph) in April. Daylight lasts from about 9.9 hours in December to 14.4 hours in June.
Best time to visit Phoenix
Based on these averages, the most comfortable months for sightseeing and outdoor activities are November–March: average highs of 19 °C66 °F to 26 °C78 °F with 19 mm0.8 in to 33 mm1.3 in of precipitation per month.
The most challenging month is July, which is hot, with average highs of 42 °C107 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
Phoenix weather by month
- January19 °C67 °F / 6 °C42 °F
- February21 °C70 °F / 7 °C44 °F
- March26 °C78 °F / 10 °C50 °F
- April30 °C86 °F / 13 °C56 °F
- May35 °C96 °F / 18 °C65 °F
- June42 °C107 °F / 24 °C76 °F
- July42 °C107 °F / 28 °C83 °F
- August41 °C105 °F / 27 °C81 °F
- September38 °C101 °F / 24 °C75 °F
- October32 °C90 °F / 17 °C63 °F
- November25 °C77 °F / 11 °C51 °F
- December19 °C66 °F / 5 °C42 °F
What to pack for Phoenix
- Winter (December–February) — highs 1966 to 21 °C70 °F, lows 542 to 7 °C44 °F, about 32 mm1.3 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Spring (March–May) — highs 2678 to 35 °C96 °F, lows 1050 to 18 °C65 °F, about 12 mm0.5 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water and an extra layer for the cooler mornings and evenings.
- Summer (June–August) — highs 41105 to 42 °C107 °F, lows 2476 to 28 °C83 °F, about 23 mm0.9 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water.
- Autumn (September–November) — highs 2577 to 38 °C101 °F, lows 1151 to 24 °C75 °F, about 19 mm0.7 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water and an extra layer for the cooler mornings and evenings.
How Phoenix compares
Of the 222 places in the United States covered by World Climates, Phoenix is the 7th warmest by annual mean temperature and the 214th wettest by annual precipitation. See all of them on the United States climate page.
Places in other countries with the most similar temperature and rainfall pattern: Mexicali (Mexico, BWh), San Luis Río Colorado (Mexico, BWh) and Biskra (Algeria, BWh).
The same NASA POWER grid cell also contains Glendale (pop. 240,126). Their long-term averages in this dataset are essentially the same as for Phoenix, so they do not have separate pages.
Nearby places
- Peoria 21 km · 23 °C74 °F · 193 mm7.6 in
- Mesa 24 km · 23 °C74 °F · 256 mm10 in
- Tucson 173 km · 21 °C70 °F · 324 mm13 in
- Yuma 251 km · 23 °C74 °F · 99 mm3.9 in
- Nogales 261 km · 18 °C65 °F · 359 mm14 in
- San Luis Río Colorado 275 km · 24 °C74 °F · 84 mm3.3 in
- Mexicali 328 km · 24 °C76 °F · 126 mm5.0 in
- Henderson 392 km · 21 °C70 °F · 147 mm5.8 in
Frequently asked questions
What is the warmest month in Phoenix?
July is the warmest month in Phoenix, with an average high of 42 °C (107 °F) and an average low of 28 °C (83 °F).
What is the coldest month in Phoenix?
December is the coldest month, with an average high of 19 °C (66 °F) and an average low of 5 °C (42 °F).
When does it rain the most in Phoenix?
August is the wettest month with about 33 mm (1.3 in) of precipitation; June is the driest with about 2 mm (0.1 in).
What is the best time to visit Phoenix?
Judging by long-term averages, the most comfortable months are November–March.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 494 m, while Phoenix lies at about 331 m. Temperatures on this page were therefore adjusted by +1.1 °C1.9 °F using the standard lapse rate of 6.5 °C per 1,000 m.