The Southwest region is expected to experience between 0 and 25 fewer days per year with a minimum temperature below 10 degrees Fahrenheit by the middle of the century.

The largest decreases are expected in the northern half of the region, particularly in high-elevation areas. The smallest decrease in cold days is expected coastal and southern parts of the region, where these kinds of cold days rarely occur. High elevation areas could have up to 60 fewer days each year with minimum temperatures below 32° F (0°C) by the mid century, when compared to the period 1976 - 2005.