The University of Arizona

Monsoon Recap | CLIMAS

 SW Climate Outlook

Monsoon Recap

Monsoon Recap (June 15 –– Sep 30)

Looking back on the 2014 monsoon, a simple characterization of the season as ‘normal’ or ‘average’ (or above or below these thresholds) is difficult, given the spatial and temporal variability of monsoon storms. The cumulative seasonal totals provide one way of characterizing the monsoon, and by those metrics, the Southwest saw an average to above-average summer rainy season, with much of Arizona and New Mexico receiving well above-average rainfall. 

Most of Arizona received well above-average monsoon rainfall—200 to 400 percent of average—and many     areas in the state registered 150 percent of their seasonal total or higher. The exceptions were across most of the Four Corners region and in portions of Pima, Pinal, and Graham counties (Fig. 1a). Precipitation intensity (Fig. 2a) identifies areas that received a significant portion of their monsoon precipitation in a few extreme events, with the Phoenix metropolitan area and portions of western Arizona being prime examples of more intense precipitation. Figure 3a (the percentage of days observing 0.01 inch of rain or more) further illustrates this pattern by highlighting areas that received more frequent and steady rain (e.g., much of the southeastern portion of the state) compared to areas with much less frequent rain (e.g., Phoenix, western Arizona, and the Four Corners region).

New Mexico saw a similarly strong, if not stronger, monsoon, with most areas of the state receiving more than 200 percent of their seasonal average and large swaths of southern New Mexico recording between 300 and 400 percent of their seasonal average (Fig. 1b). The exceptions were the Four Corners region and the northeastern corner of the state. New Mexico monsoon precipitation intensity (Fig. 2b) shows a relatively even pattern, with more widespread coverage and less variability compared to Arizona. The graphic depicting percent of days with rain in New Mexico (Fig. 3b) shows larger areas of more frequent but less intense precipitation, with a large percentage of the state experiencing measurable precipitation on at least a third of days during the monsoon.