If you’re planning on visiting Grand Canyon National Park, you need to be aware of the region’s seasonal weather patterns. Grand Canyon weather varies significantly throughout the year. Summers on the South Rim are hot with regular thunderstorms. Winters on the North Rim typically bring 12 feet of snow. The coldest temperature ever recorded in Grand Canyon was -22˙F (-30˙C) on the North Rim. The hottest temperature ever recorded in the park was 120˙F (49˙C) at Phantom Ranch. If you arrive unprepared for these seasonal conditions, it can ruin your trip. But take some time to learn about Grand Canyon weather, and you can safely enjoy one of the earth’s most incredible destinations.
Grand Canyon Weather Patterns
Because Grand Canyon is located in the arid Southwest, it receives much less precipitation than most parts of the United States. But there is tremendous variation within Grand Canyon. The South Rim receives an average of 17 inches (43 cm) of precipitation each year, while the North Rim receives an average of 26 (66 cm) inches of precipitation. Phantom Ranch, located at the bottom of Grand Canyon, averages less than 10 inches (25 cm) of precipitation. Despite these variations, precipitation in Grand Canyon arrives in a fairly predictable pattern, falling in winter and summer in a nearly 50/50 split.
In the summer, prevailing winds from the south carry moisture from the Gulf of California. As moist air passes over Arizona, it rises up and over the highlands just south of Grand Canyon, arriving at the Canyon cool and condensed. In the morning, when the sun heats the Inner Canyon, hot air rises and collides with the cool, moist air above. This sudden collision creates short-lived afternoon thunderstorms. In July, August and early September (a period referred to as “monsoon season”), these storms hit Grand Canyon on an almost daily basis.
In the winter, prevailing winds arrive from the west or northwest, bringing moist air from the Pacific Ocean. The vast majority of this moisture is wrung out by the Sierra Nevada Mountains to the west, but some moisture does find its way into northern Arizona. Although winter storms in Grand Canyon are much less intense than summer storms, they often linger for days. Snowfall is significantly greater on Grand Canyon’s North Rim, which is typically closed from November to May due to heavy snow.
In the spring and the fall, Grand Canyon becomes extremely arid, resulting in dramatic temperature swings. Dry air allows up to 90 percent of solar radiation to reach the ground during the day. At night, however, the situation is reversed, and 90 percent of the Canyon’s accumulated heat radiates back into the atmosphere through clear, dry skies. In humid areas, by contrast, only 40 percent of solar radiation reaches the ground during the day, but that heat is often reflected back by an insulating cloud cover at night.
Plan the perfect Grand Canyon vacation for less than the cost of lunch!
Order Grand Canyon: The Complete Guide
"Head and shoulders above the rest of the books on the Grand Canyon. Simply the best there is on this subject." — S.M. Jenkins (Amazon customer)View on Amazon