The Grand Canyon is so large it actually has the ability to create its own weather. From an elevation of over 8,000 feet on the North Rim to 2,000 feet at Phantom Ranch along the Colorado River, weather at the Grand Canyon varies greatly depending on your location and the time of year. Weather on the South Rim has four seasons with average summer highs in the mid 80s, while temperatures along the Colorado River can soar over 110 degrees and snowfall has rarely been seen.
Overall the best seasons to visit the Canyon are Spring and Fall, as they offer the best weather to enjoy everything the area has to offer, especially for hikers. The summer is hot, even at 7,000 in Grand Canyon village, but it is a good time to visit the North Rim (which is only open seasonally), or to go rafting on the Colorado River. The summer is also a nice time to enjoy Havasu Falls, and the other waterfalls of Havasu Canyon. The winter season can be cold and snowy, but it is still Arizona with average highs in the 40s and a 95% chance of sunshine sometime each day. The winter season also offers the most solitude for those of you who want to avoid hordes of tourists.