Southwest Climate Outlook August 2014

Date issued

Precipitation: Much of Arizona and New Mexico received average to above-average precipitation in the past 30 days, although as is often the case with the monsoon, precipitation intensity and location were inconsistent. New Mexico experienced more consistent precipitation, and central New Mexico saw a number of storms that brought considerable moisture. Arizona’s monsoon has been patchy in nature, with large storm events, but fewer areas seeing repeated rainfall events. Many areas with above-average seasonal totals received most of their rainfall from just one or two large storms.

Temperature: Monsoon storms drove short-term temperature variability on a day-to-day basis, but over the past 30 days, most of Arizona and New Mexico experienced near-average temperatures.

Water Supply: In Arizona, total reservoir storage dropped by about 340,000 acre-feet (AF) in July, putting total reservoir capacity at 46 percent (compared to 48 percent last year). In New Mexico, total reservoir storage dropped 100,000 AF in July, putting total reservoir capacity at 22 percent (compared to 16 percent last year). Lake Mead and the Colorado River Basin received significant media attention in light of falling reservoir levels and the ongoing drought in the West. Our podcast series on the Colorado River (“1075”) features extended conversations with regional experts on these issues.

Drought: Monsoon precipitation scaled back short-term drought conditions in Arizona and New Mexico, especially in the categories between severe and exceptional drought. This reduction reflects steady monsoon precipitation in New Mexico, and links to ongoing discussions about the extent to which monsoon moisture actually helps mitigate long-term drought.

Monsoon: Monsoon precipitation was variable across much of Arizona, with some regions (such as western Arizona) well above average for total monsoon precipitation thus far, and other areas (such as the Four Corners area) below monsoon average. A series of powerful monsoon storms drenched central New Mexico, and most of the state has tallied well-above-average monsoon precipitation, with the exception of the Four Corners region and the southeast.

ENSO: ENSO-neutral conditions continue, and August projections reduced the probability of an El Niño event developing from 80 percent to 65 percent. The potential strength of an El Niño event now is projected as weak to moderate, with little indication that it could develop into a strong event. A recent dip in sea-surface temperatures contributed to this dampened enthusiasm, but ongoing conditions still support the likely formation of an El Niño event later this fall or early winter.

Precipitation & Temperature Forecasts: The monsoon is expected to continue to bring storms and moisture into the region. Longer-term forecasts point toward above-average precipitation for Arizona and New Mexico, especially as conditions remain favorable for the development of an El Niño event. In the near term there is increased probability of above-average temperatures, but as we approach fall and winter, the prospect of an El Niño event, regardless of strength, suggests an increased probability of below-average temperatures for the Southwest.

Published by the Climate Assessment for the Southwest (CLIMAS), with support from University of Arizona Cooperative Extension, the Arizona State Climate Office, and the New Mexico State Climate office.

Disclaimer. This packet contains official and non-official forecasts, as well as other information. While we make every effort to verify this information, please understand that we do not warrant the accuracy of any of these materials. The user assumes the entire risk related to the use of this data. CLIMAS, UA Cooperative Extension, and the State Climate Office at Arizona State University (ASU) disclaim any and all warranties, whether expressed or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose. In no event will CLIMAS, UA Cooperative Extension, and the State Climate Office at ASU or The University of Arizona be liable to you or to any third party for any direct, indirect, incidental, consequential, special or exemplary damages or lost profit resulting from any use or misuse of this data.