Autumn, when the wet season ends, the stifling desert temperatures moderate (it's 20 degrees cooler than Phoenix), and the mountain aspens reach their full golden splendor, is a great time to visit this part of Arizona. During the summer months many Phoenix residents travel north to escape the 100-degree temperatures, meaning excessive traffic along Interstate 17 just north of Phoenix on Friday and Sunday evenings. Hotels are less expensive in winter, but mountain temperatures dip below zero, and snowstorms can occur weekly, especially near Flagstaff.
Sedona has springlike temperatures even in January, when it's snowing in Flagstaff, but summer temperatures above 90°F are common.
Prescott and Flagstaff hold most of their festivals and cultural events in summer. Sedona's biggest event, the Jazz on the Rocks Festival, takes place in September.