Superior, AZ climate
Superior has mild winters and scorching summers, with very little rain. A typical July afternoon reaches 101°, a January night drops to 39°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Superior feels like
Winter
Spring
Summer
Fall
Superior 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 | 63° | 39° | 2.0" | 0 | 5 | 0 | 47° – 58° |
| February | 66° | 41° | 1.9" | 0.3" | 6 | 0 | 48° – 59° |
| March | 73° | 45° | 1.6" | 0 | 6 | 0 | 51° – 66° |
| April | 81° | 50° | 0.5" | 0 | 2 | 0 | 60° – 70° |
| May | 90° | 58° | 0.3" | 0 | 2 | 0 | 68° – 79° |
| June | 100° | 68° | 0.2" | 0 | 1 | 0 | 78° – 87° |
| July | 101° | 74° | 1.6" | 0 | 5 | 0 | 85° – 90° |
| August | 99° | 73° | 2.1" | 0 | 8 | 0 | 83° – 90° |
| September | 95° | 68° | 1.3" | 0 | 3 | 0 | 77° – 84° |
| October | 85° | 56° | 0.9" | 0 | 3 | 0 | 67° – 76° |
| November | 72° | 46° | 1.1" | 0 | 3 | 0 | 50° – 65° |
| December | 62° | 39° | 1.7" | 0 | 4 | 0 | 47° – 54° |
| Year | 82° | 55° | 15.0" | 0.3" | 49 | 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 Superior
Superior gets 15 inches of rain and melted snow a year. August is the wettest month and June the driest. Rain or snow falls on about 49 days a year.
A year-round growing season
Heating and cooling a home in Superior
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Superior, 30% of that work is heating and 70% 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.
How Superior 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 Superior averaged 1.8° warmer than the 1900s. The biggest change is in March (+2.8°). The shift is larger than in 87% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Superior’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. March swings the most: between 1991 and 2020 its average temperature ranged from 51° to 66°. July is the most reliable, staying within 5°.
Common questions about Superior’s climate
What is the coldest month in Superior?
December, with a typical high of 62° and a low of 39°.
What is the hottest month in Superior?
July, with a typical high of 101° and a low of 74°. About 129 days a year reach 90°.
How much snow does Superior get?
Almost none. A normal year brings 0.3 inches.
When is the first frost in Superior?
Frost is uncommon. Only 77% of years see a night at 32° or below.
What is the rainiest month in Superior?
August, with 2.1 inches of rain and melted snow. The year totals 15 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Superior itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Superior, AZ (3 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.