Oro Valley, AZ climate
Oro Valley has mild winters and hot summers, with very little rain. A typical July afternoon reaches 100°, a January night drops to 38°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Oro Valley feels like
Winter
Spring
Summer
Fall
Oro 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 | 65° | 38° | 1.2" | 0 | 4 | 0 | 47° – 57° |
| February | 68° | 40° | 1.2" | 0 | 4 | 0 | 48° – 59° |
| March | 74° | 45° | 0.9" | 0 | 3 | 0 | 53° – 65° |
| April | 81° | 50° | 0.3" | 0 | 1 | 0 | 59° – 71° |
| May | 90° | 58° | 0.2" | 0 | 1 | 0 | 69° – 79° |
| June | 100° | 68° | 0.2" | 0 | 1 | 0 | 79° – 87° |
| July | 100° | 73° | 2.0" | 0 | 6 | 0 | 83° – 89° |
| August | 98° | 72° | 2.3" | 0 | 8 | 0 | 83° – 90° |
| September | 94° | 67° | 1.4" | 0 | 4 | 0 | 76° – 83° |
| October | 85° | 56° | 0.6" | 0 | 3 | 0 | 67° – 75° |
| November | 74° | 45° | 0.8" | 0 | 2 | 0 | 51° – 66° |
| December | 64° | 38° | 1.4" | 0 | 4 | 0 | 46° – 55° |
| Year | 83° | 54° | 12.6" | 0.0" | 40 | 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 Oro Valley
Oro Valley gets 13 inches of rain and melted snow a year. August is the wettest month and May the driest. Rain or snow falls on about 40 days a year.
About 279 frost-free days a year
In half of years the last 32° night comes by February 26 and the first one by December 4. That leaves about 279 frost-free days for gardens, longer than 93% of U.S. towns.
Heating and cooling a home in Oro Valley
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Oro Valley, 33% of that work is heating and 67% 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.
Oro Valley and its neighbors
Oro Valley borders 2 towns with climate data. January nights across them vary by 2.9°. Catalina has the coldest January nights (35°) and Casas Adobes the hottest July afternoons (101°). Oro Valley’s January low is 38° and its July high 100°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Oro 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 Oro Valley averaged 1.4° warmer than the 1900s. The biggest change is in March (+2.4°). The shift is larger than in 64% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Oro Valley’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 51° to 66°. July is the most reliable, staying within 5°.
Common questions about Oro Valley’s climate
What is the coldest month in Oro Valley?
December, with a typical high of 64° and a low of 38°.
What is the hottest month in Oro Valley?
June, with a typical high of 100° and a low of 68°. About 159 days a year reach 90°.
How much snow does Oro Valley get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Oro Valley?
In half of years the first 32° night comes by December 4, and the last spring frost by February 26.
What is the rainiest month in Oro Valley?
August, with 2.3 inches of rain and melted snow. The year totals 13 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Oro Valley itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Tucson Camp Ave Exp, AZ (10 mi, snow) and Tohono Chul, AZ (6 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.