Weather conditions are very diverse on the Canyon because of the wide range of elevations that the Canyon covers. Temperatures rise 5.5 degrees Fahrenheit for every 1,000 ft. drop in elevation, which explains the wide variety of temperatures each season. Make sure to bring clothing to be comfortable in a wide range of temperatures to make your visit pleasant.
Winter in the canyon can see temperatures on the rim ranging from 20 to 40 degrees Fahrenheit on the South Rim and 36 to 56 degrees in the inner Canyon. There is often snow in the winter time which is an incredible opportunity to see desert vistas covered in snow. Roads on the South Rim are plowed but many times trails will be closed due to icy conditions. The North Rim is not open during the winter time and shuts down once the first major snow comes through.
Summer temperatures on both rims are very pleasant with temperatures ranging from 40 to 84 degrees Fahrenheit. Temperatures in the Canyon gorge can become quite hot mirroring the deserts much further south of the park. Temperatures range from 92 to 106 degrees Fahrenheit and require that anyone who ventures into the Canyon must be prepared to manage the heat.
During the monsoon season there is the danger of flash floods in the inner canyon as well as lightning strikes on both rims. Use caution when traveling during monsoon season as storms can strike suddenly.