Southwest Climate Outlook July 2020 - Climate Summary

July 14, 2020
Ben McMahan

Monthly Precipitation and Temperature: June precipitation ranged between record driest and average in most of Arizona, and between below average and average in most of New Mexico (Fig. 1a). June temperatures were above average or much above average in nearly all of Arizona and New Mexico (Fig. 1b). The daily average temperature anomalies for Jun 1 – Jul 13 (Fig. 2) highlight the fluctuations at stations around the region (see July Temperature Breakdown)

Figure 1

Seasonal Precipitation and Temperature: 2020 precipitation (Jan-Jun) ranged from below average to muchabove average in Arizona, and from much below average to above average in New Mexico (Fig. 3a). 2020 temperatures (Jan-Jun) were above average to much above average across the U.S. Southwest (Fig. 3b).

Figure 3

Water Supply: Water year precipitation to date (Oct – Jun) is above normal to much above normal across most of southern and central Arizona and New Mexico, along with west Texas and southern California (Fig. 4). The Four Corners region, northern New Mexico, and southern Colorado are all below normal or much below normal with pockets of record driest (Fig. 4). Many of the reservoirs in the region are at or above the values recorded at this time last year, but most are below their long-term average (see Arizona and New Mexico reservoir storage).

Drought: The Jul 7 U.S. Drought Monitor (USDM) maintains drought characterizations in the Four Corners region while expanding severe and extreme drought characterizations (D2 and D3, respectively) in southern Colorado, and northern and eastern New Mexico. (Fig. 5).

Wildfire: Arizona, eastern and northern New Mexico, southwestern Colorado, and most of Utah and Nevada are above normal for wildfire risk in July. Arizona has seen considerable fire activity in 2020, including the Bighorn fire near Tucson, the Sawtooth and Bush fires near Phoenix, and the Mangum fire in northern Arizona. Wildfire acres burned for 2020 are already above the long term mean and median, as well as the totals for each of the past five years for Arizona, while New Mexico remains below mean/median in 2020 (Fig. 6, data as of Jul 12).

ENSO Tracker: Conditions are expected to remain ENSO-neutral through summer 2020, with increased chances of a La Niña event this fall.

Precipitation and Temperature Forecast: The three-month outlook for Aug through Oct calls for equal chances of above- or below-normal precipitation in most of Arizona, New Mexico, Texas, and northern Mexico (Fig. 7, top). The three-month temperature outlook calls for increased chances of above-normal temperatures across most of the western U.S. and northern Mexico (Fig. 7, bottom).

Online Resources

  • Figures 1, 3 - National Centers for Environmental Information - ncei.noaa.gov
  • Figure 2, 6 - Climate Assessment for the Southwest - climas.arizona.edu
  • Figure 4 - West Wide Drought Tracker - wrcc.dri.edu/wwdt
  • Figure 5 - U.S. Drought Monitor - droughtmonitor.unl.edu
  • Figure 7 - International Research Institute for Climate and Society - iri.columbia.edu