Phoenix, AZ climate
Phoenix has warm winters and scorching summers, with very little rain. A typical July afternoon reaches 105°, a January night drops to 42°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Phoenix feels like
Winter
Spring
Summer
Fall
Phoenix weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 67° | 42° | 0.9" | 0.1" | 3 | 0 | 51° – 60° |
| February | 71° | 45° | 1.1" | 0.1" | 3 | 0 | 52° – 63° |
| March | 78° | 49° | 1.0" | 0 | 3 | 0 | 56° – 70° |
| April | 85° | 55° | 0.2" | 0 | 1 | 0 | 64° – 75° |
| May | 94° | 63° | 0.1" | 0 | 1 | 0 | 73° – 83° |
| June | 103° | 72° | 0.0" | 0 | 0 | 0 | 82° – 91° |
| July | 105° | 80° | 0.8" | 0 | 3 | 0 | 89° – 96° |
| August | 104° | 79° | 1.0" | 0 | 3 | 0 | 88° – 96° |
| September | 99° | 73° | 0.6" | 0 | 2 | 0 | 82° – 88° |
| October | 88° | 60° | 0.5" | 0 | 1 | 0 | 71° – 79° |
| November | 76° | 48° | 0.6" | 0 | 2 | 0 | 54° – 68° |
| December | 66° | 41° | 0.9" | 0 | 3 | 0 | 51° – 57° |
| Year | 86° | 59° | 7.9" | 0.2" | 23 | 0 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Phoenix
Phoenix gets 8 inches of rain and melted snow a year. February is the wettest month and June the driest. Rain or snow falls on about 23 days a year.
About 331 frost-free days a year
In half of years the last 32° night comes by January 20 and the first one by December 15. That leaves about 331 frost-free days for gardens, longer than 96% of U.S. towns.
Heating and cooling a home in Phoenix
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Phoenix, 26% of that work is heating and 74% is cooling, so air conditioning is the bigger bill.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Phoenix and its neighbors
Phoenix borders 11 towns with climate data. January nights across them vary by 3.6°. Tempe has the coldest January nights (41°) and Maricopa Colony the hottest July afternoons (106°). Phoenix’s January low is 42° and its July high 105°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Phoenix compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Phoenix averaged 2.3° warmer than the 1900s. The biggest change is in March (+3.1°). The shift is larger than in 99% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Phoenix’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. November swings the most: between 1991 and 2020 its average temperature ranged from 54° to 68°. July is the most reliable, staying within 6°.
Common questions about Phoenix’s climate
What is the coldest month in Phoenix?
December, with a typical high of 66° and a low of 41°.
What is the hottest month in Phoenix?
July, with a typical high of 105° and a low of 80°. About 175 days a year reach 90°.
How much snow does Phoenix get?
Almost none. A normal year brings 0.2 inches.
When is the first frost in Phoenix?
In half of years the first 32° night comes by December 15, and the last spring frost by January 20.
What is the rainiest month in Phoenix?
February, with 1.1 inches of rain and melted snow. The year totals 8 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Phoenix itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Tolleson 1 E, AZ (12 mi, snow) and Youngtown, AZ (12 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.