Sun Valley, AZ climate
Sun Valley has chilly winters and hot summers, with very little rain. A typical July afternoon reaches 93°, a January night drops to 21°, and about 4 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Sun Valley feels like
Winter
Spring
Summer
Fall
Sun Valley 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 | 49° | 21° | 0.7" | 0.8" | 6 | 0 | 25° – 41° |
| February | 56° | 25° | 0.6" | 0.6" | 5 | 0 | 35° – 46° |
| March | 64° | 30° | 0.7" | 0.8" | 5 | 0 | 42° – 52° |
| April | 71° | 36° | 0.4" | 0 | 3 | 0 | 48° – 58° |
| May | 80° | 44° | 0.4" | 0 | 4 | 0 | 57° – 66° |
| June | 91° | 53° | 0.2" | 0 | 2 | 0 | 67° – 76° |
| July | 93° | 61° | 1.3" | 0 | 9 | 0 | 73° – 81° |
| August | 90° | 60° | 1.5" | 0 | 9 | 0 | 72° – 79° |
| September | 84° | 52° | 1.0" | 0 | 5 | 0 | 64° – 71° |
| October | 73° | 39° | 0.8" | 0.2" | 5 | 0 | 52° – 61° |
| November | 60° | 28° | 0.6" | 0.3" | 4 | 0 | 37° – 51° |
| December | 48° | 21° | 0.7" | 0.8" | 5 | 1 | 29° – 41° |
| Year | 72° | 39° | 8.7" | 3.5" | 62 | 2 |
“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 Sun Valley
Sun Valley gets 9 inches of rain and melted snow a year. August is the wettest month and June the driest. Rain or snow falls on about 62 days a year.
About 162 frost-free days a year
In half of years the last 32° night comes by May 4 and the first one by October 16. That leaves about 162 frost-free days for gardens, shorter than 69% of U.S. towns.
Heating and cooling a home in Sun Valley
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Sun Valley, 81% of that work is heating and 19% is cooling, so the furnace matters far more than the air conditioner.
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 Sun Valley 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 Sun Valley averaged 1.5° warmer than the 1900s. The biggest change is in March (+2.7°). The shift is larger than in 73% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Sun Valley’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 25° to 41°. August is the most reliable, staying within 7°.
Common questions about Sun Valley’s climate
What is the coldest month in Sun Valley?
January, with a typical high of 49° and a low of 21°.
What is the hottest month in Sun Valley?
July, with a typical high of 93° and a low of 61°. About 72 days a year reach 90°.
How much snow does Sun Valley get?
About 4 inches in a normal winter, most of it in January.
When is the first frost in Sun Valley?
In half of years the first 32° night comes by October 16, and the last spring frost by May 4.
What is the rainiest month in Sun Valley?
August, with 1.5 inches of rain and melted snow. The year totals 9 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Sun Valley itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Petrified Forest Np, AZ (14 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.