Casa Grande, AZ climate
Casa Grande has mild winters and scorching summers, with very little rain. A typical July afternoon reaches 106°, a January night drops to 39°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Casa Grande feels like
Winter
Spring
Summer
Fall
Casa Grande 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 | 68° | 39° | 0.8" | 0 | 4 | 0 | 50° – 58° |
| February | 71° | 42° | 0.9" | 0 | 4 | 0 | 51° – 61° |
| March | 78° | 47° | 0.8" | 0 | 3 | 0 | 54° – 69° |
| April | 86° | 53° | 0.2" | 0 | 1 | 0 | 64° – 74° |
| May | 95° | 61° | 0.2" | 0 | 1 | 0 | 72° – 84° |
| June | 105° | 70° | 0.1" | 0 | 1 | 0 | 82° – 91° |
| July | 106° | 78° | 1.0" | 0 | 3 | 0 | 89° – 94° |
| August | 104° | 77° | 1.3" | 0 | 5 | 0 | 87° – 95° |
| September | 100° | 71° | 0.7" | 0 | 3 | 0 | 81° – 87° |
| October | 89° | 58° | 0.4" | 0 | 2 | 0 | 70° – 78° |
| November | 77° | 46° | 0.5" | 0 | 2 | 0 | 53° – 67° |
| December | 66° | 38° | 0.8" | 0 | 4 | 0 | 49° – 56° |
| Year | 87° | 56° | 7.8" | 0.0" | 31 | 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 Casa Grande
Casa Grande gets 8 inches of rain and melted snow a year. August is the wettest month and June the driest. Rain or snow falls on about 31 days a year.
About 305 frost-free days a year
In half of years the last 32° night comes by February 5 and the first one by December 6. That leaves about 305 frost-free days for gardens, longer than 95% of U.S. towns.
Heating and cooling a home in Casa Grande
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Casa Grande, 24% of that work is heating and 76% 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.
Casa Grande and its neighbors
Casa Grande borders 2 towns with climate data. January nights across them vary by 0.4°. Maricopa has both the coldest January nights (39°) and the hottest July afternoons (106°). Casa Grande’s January low is 39° and its July high 106°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Casa Grande 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 Casa Grande averaged 1.9° warmer than the 1900s. The biggest change is in March (+2.8°). The shift is larger than in 92% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Casa Grande’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 54° to 69°. July is the most reliable, staying within 6°.
Common questions about Casa Grande’s climate
What is the coldest month in Casa Grande?
December, with a typical high of 66° and a low of 38°.
What is the hottest month in Casa Grande?
July, with a typical high of 106° and a low of 78°. About 184 days a year reach 90°.
How much snow does Casa Grande get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Casa Grande?
In half of years the first 32° night comes by December 6, and the last spring frost by February 5.
What is the rainiest month in Casa Grande?
August, with 1.3 inches of rain and melted snow. The year totals 8 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Casa Grande itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Casa Grande, AZ (3 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.