Precipitation & Temperature: June precipitation totals generally were average to above average in Arizona and New Mexico, with the exception of southern Arizona (much above average) and the Four Corners region of New Mexico (below average) (Fig. 1a). Temperatures were above average to record warm across most of the Southwest (Fig. 1b), with two periods of extreme heat (June 3-5 and June 18-20), the latter of which resulted in multiple fatalities in southern Arizona. As of July 20, temperatures this month have remained mostly above average across the Southwest (Fig. 2).
Monsoon: Following a strong start to the monsoon in late June, there was a considerable decline during much of July, aside from sporadic storms that pushed into the southeastern corner of Arizona (Fig. 3). This decline, or GÇ£break,GÇ¥ is associated with a shift in the monsoon circulation patterns, in which a high pressure ridge diverts moisture and storm activity away from southern Arizona (see Monsoon Tracker for more information).
Drought & Water Supply: Long-term drought persists across the Southwest (Fig. 4), reflecting multiple years of drought and accumulating precipitation deficits. The southern half of Arizona and the western edge of New Mexico are experiencing moderate drought, while most of the rest of these two states are designated as abnormally dry. Water year precipitation to date in Southern California, most of southern Arizona, and western New Mexico is below average (Fig. 5). Lakes Mead and Powell in Arizona and Elephant Butte Reservoir in New Mexico are at 36, 57, and 14 percent of capacity, respectively (see reservoir storage diagrams). Lake Mead is of particular interest, given water restrictions that would be triggered were levels to drop below critical thresholds (see CLIMAS 1075 podcast series).
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