Phoenix is warmest in July, averaging 42° by day and 27° at night. The wettest month is March with 40 mm, and the year brings about 252 mm in total.
Month by month
| Month | High | Low | Rain | Daylight | Good for |
|---|---|---|---|---|---|
| January | 19° | 6° | 28 mm | 10.0 h | Sightseeing |
| February | 20° | 7° | 28 mm | 10.8 h | Sightseeing |
| March | 23° | 10° | 40 mm | 11.8 h | Sightseeing |
| April | 30° | 13° | 3 mm | 12.8 h | Beach weather |
| May | 35° | 17° | 3 mm | 13.7 h | Beach weather |
| June | 41° | 23° | 6 mm | 14.2 h | Very hot |
| July | 42° | 27° | 37 mm | 14.0 h | Very hot |
| August | 41° | 27° | 40 mm | 13.2 h | Very hot |
| September | 39° | 23° | 18 mm | 12.2 h | Very hot |
| October | 33° | 17° | 9 mm | 11.1 h | Beach weather |
| November | 25° | 11° | 6 mm | 10.2 h | Beach weather |
| December | 21° | 6° | 34 mm | 9.8 h | Sightseeing |
High and low are average daily maximum and minimum, rain is typical monthly total, daylight is the hours between sunrise and sunset mid-month. Climate normals from NASA POWER — averages, not promises.
When to go
Beach weather: April, May, October and November — highs around 31°, nights no colder than 11°, and at most 9 mm of rain in a month.
Walking the city: January, February, March and December — highs of 19–23° and no more than 40 mm of rain a month.
Serious heat: In June, July, August and September the average high reaches 42°.