Phoenix, AZ – A cooler and slightly more unsettled pattern is building across the Southwest as November ends and December begins, with long-range forecasts showing lower temperatures and a renewed chance for rain and mountain snow.
According to NOAA’s Climate Prediction Center, temperatures from Nov. 29 through Dec. 5 are expected to trend below normal across Arizona, New Mexico, Nevada, Utah, and portions of Southern California. The coolest departures appear across the higher elevations of northern Arizona, Utah’s plateaus, and central New Mexico, where overnight lows may dip into the 20s and 30s.
On the precipitation side, NOAA’s outlook shows a broad but moderate signal for above-normal precipitation, especially from Arizona into New Mexico and parts of Utah. This suggests a more active storm track may allow for scattered rain, isolated valley showers, and mountain snow, depending on elevation and timing.
Higher-elevation areas — including the Mogollon Rim, the San Francisco Peaks, the Wasatch, and the Sangre de Cristo Mountains — could see periods of accumulating snow if colder air aligns with incoming moisture. Lower-elevation cities such as Phoenix, Las Vegas, Tucson, Albuquerque, and St. George may see light rain or passing showers, though widespread heavy precipitation isn’t currently indicated.
Forecasters emphasize this is primarily a pattern shift, not a major storm signal. Still, the combination of colder air and increased moisture could bring localized travel impacts, especially on mountain passes and high desert routes along I-40, I-17, US-89, and I-25.
With temperatures dropping and early December approaching, Southwest residents should monitor their local forecasts for storm timing and snowfall potential in nearby high terrain.
