Temperature

Temperatures since the water year began on October 1 have averaged between 30 and 50 degrees Fahrenheit in New Mexico and the Colorado Plateau, while the southwest deserts of Arizona have averaged between 50 and 65 degrees F (Figure 1a). The coldest temperatures have been in the higher elevations in Arizona and in the northern counties of New Mexico. Temperatures have been mostly within 1 degree F of average across both states (Figure 1b). The distribution of warmer- and colder-than-average areas is related to the winter storm tracks, which have been highly variable throughout this winter. For the most part, cold air has stayed far to the north, which is in part related to positive Arctic Oscillation (AO) values—cold air is generally confined in the Arctic region during a positive AO. A few cold storms have wafted as far south as northern Mexico, catching southern Arizona and New Mexico as they past.  

In the past 30 days, two winter storms have moved across the Southwest, bringing cold air and 1–6 degree F below-average temperatures in Arizona and western New Mexico (Figures 1c–d). Eastern New Mexico has been the only area with above-average temperatures; the jet stream looped farther north and into Canada, which allowed temperatures to rise 10–20 degrees F above average over many parts of the central U.S.