The sun rises in the East, just as it does everywhere on Earth. However, the precise point on the horizon shifts daily due to the Earth’s movement. This daily shift, combined with Arizona’s unique timekeeping policy and diverse landscape, makes the seemingly simple question a detailed scientific and geographic discussion.
The Science of the Changing Sunrise Direction
The point on the horizon where the sun appears is called the sunrise azimuth, and it constantly changes throughout the year. This daily shift results from the Earth’s axial tilt, causing the sun’s position relative to the horizon to migrate seasonally. The sun rises precisely at true East only twice a year, during the spring and autumn equinoxes.
For the remainder of the year, the sunrise point deviates significantly north or south. During the summer, leading up to the Summer Solstice (around June 21), the sun rises in the Northeast. Conversely, during the winter, the sun rises in the Southeast, reaching its southernmost point around the Winter Solstice (December 21). At Arizona’s latitude, the sun’s rising point spans approximately 60 degrees on the eastern horizon.
How Arizona’s Time Zone Affects Sunrise Clocks
Most of Arizona operates on Mountain Standard Time (MST), which is UTC-7, year-round and does not participate in Daylight Saving Time (DST). This timekeeping policy is important because the clock time for sunrise behaves differently than in surrounding states. The only major exception is the Navajo Nation in the northeastern part of the state, which observes DST.
When the rest of the United States “springs forward,” Arizona’s clocks remain unchanged. During the summer, this places most of Arizona on the same clock time as the Pacific Daylight Time Zone. Consequently, summer sunrises in cities like Phoenix occur relatively earlier by the clock than they would if the state observed DST. Because Arizona remains on MST, residents experience an earlier start to the day.
Geographic Factors Influencing the View
Arizona’s physical landscape significantly influences the visual experience and the perceived timing of the sunrise. In the vast, flat desert regions of Southern Arizona, the horizon is often unobstructed, providing a clear view of the astronomical sunrise. Here, the difference between the calculated time and the observed time is minimal, primarily affected by atmospheric refraction.
The state also features extensive mountain ranges and high plateaus, such as the Mogollon Rim. When a mountain range stands to the east of an observer, it effectively raises the local horizon. This physical obstruction can delay the actual moment the sun becomes visible by several minutes, regardless of the calculated time for a flat horizon. Furthermore, higher elevations, which are common across the state, allow an observer to see the sun appear sooner than someone at a lower altitude due to the curvature of the Earth.