Energetic monsoon brings moisture surplus to many areas
By Summit Voice
FRISCO — An energetic and widespread monsoon weather pattern brought above normal precipitation to much of the West in August, with a bullseye of moisture in southern Idaho, extending across western Wyoming, Montana, northeastern Utah and into northwestern Colorado. Some locations in the region saw up to 800 percent of average precipitation.
Parts of the Southern California desert also saw a moisture surplus, but the parts of California hardest hit by the drought did not get much relief, and extremely dry conditions extended up the West Coast into Oregon and Washington.
In Colorado, August precipitation was above-average across the northwestern third of the state and in parts of the northeastern plains, while the south-central part of the state remained dry.
For the weather year (starting Oct, 1, 2013), it’s a slightly different story. Most of the Southwest is still reporting a moisture deficit, with a few exceptions in north-central Arizona and New Mexico. Much of Utah and southern Colorado are about 20 to 30 percent below average, but northern Colorado shows a surplos of 10 to 20 percent.
But all that July rain didn’t translate into extra water for Lake Powell, the key reservoir on the Colorado River, where the monthly inflow was just 70 percent of average, leaving Powell just barely more than half full. Still, 2014 was a huge improvement over last year, with the expected annual inflow projected at about 94 percent of average.
Weather and climate experts say they’re still not sure if an El Niño will emerge in the next few months, and they’ve dialed back expectations. According to the latest projections, there’s now only about a 60 percent to 70 percent chance of an El Niño this winter. But sea surface temperatures in the equatorial Pacific have been running slightly above average the past few months, near the El Niño threshold.
Those conditions may contribute to above-average precipitation in the Southwest and the south-central regions, according to the Climate Prediction Center.