Temperature

Average temperatures since the water year began on October 1 generally have ranged from 30 to 50 degrees Fahrenheit on the Colorado Plateau and across the northern two-thirds of New Mexico (Figure 1a). Average temperatures have been 45–55 degrees F in southern New Mexico; 55–70 degrees F in southwestern Arizona, and 30–35 degrees F in the highest elevations in northern New Mexico. These temperatures have been within 2 degrees F of the 30 year average across most of Arizona (Figure 1b). Central and southern Arizona have been slightly cooler than average, while south-central Arizona and the northeastern corner have been warmer than average. The southeastern quarter of New Mexico has been 0–3 degrees F warmer than average, while the rest of the state has been 0–4 degrees F cooler than average.  

The past 30 days have been 0–4 degrees F colder than average across most of both southwestern states. The only areas with warmer-than-average temperatures have been around the southern border of Arizona and New Mexico, northwestern Arizona, and the Four Corners region (Figures 1c–d). Parts of the high elevation areas in northern New Mexico and Pima County in southern Arizona have been 4–6 degrees F colder than average. The recent chilly temperatures are attributed to several unusually cold winter storms that tapped polar air as they wafted south along the West Coast. This is unusual for a La Niña circulation pattern, which tends to push storms north of the region. However, last winter also had numerous cold winter storms through December before conditions dried and warmed in January.