Annual Weather

Picacho Peak State Park is centrally located in the Sonoran Desert between Tucson and Phoenix, and the local climate is characterized by some of the hottest summer temperatures in the country. “But it’s a dry heat!”—low humidity readings make the heat more tolerable than comparable temperatures would be in more humid climates.

The high season at the park is from late fall into spring, when the park offers a place to experience the mild temperatures and endless hours of sunshine that make Southern Arizona one of the most desirable locations during the winter months. Daily high temperatures are often still in the upper 60s in January (the coldest month), making it very pleasant for a variety of outdoor activities. Only occasionally do the overnight lows drop below 30 degrees in December and January.

Two rainy seasons provide the scarce precipitation that life in the Sonoran Desert depends on for survival. Soft winter rains that can last a few hours generally occur between October and March. Above-average winter precipitation is a precondition for a noteworthy wildflower season in the following spring. The much more violent thunderstorms that characterize the so-called summer “monsoon season” can drench the park with heavy downpours from July until September. These usually short-lived afternoon showers are usually the result of clouds building through the day.

Picacho Peak can be an exciting place to visit year-round if you come prepared for the varying weather conditions that are so typical for the deserts of the world. Below is a listing of average daily temperatures and monthly precipitation:

Picacho Peak State Park 
Average Daily Temperature (Degrees Fahrenheit)
& Monthly Precipitation (Inches)
Month Temperature Precipitation
High Low
January 66° F 40° F 0.86"
February 71° 43° 1.22"
March 76° 47° 1.18"
April 85° 53° 0.38"
May 94° 61° 0.22"
June 104° 71° 0.13"
July 105° 77° 0.83"
August 102° 76° 1.91"
September 98° 71° 0.78"
October 88° 59° 0.67"
November 75° 47° 0.66"
December 66° 40° 1.23"

Note: Weather data is provided as a general guide only. Arizona State Parks assumes no responsibility for any loss resulting from the use of this information.