The latest monthly outlook from the U.S. Drought Monitor shows drought conditions are expected to improve across portions of the Great Basin and Four Corners region through August, driven by an active monsoon pattern. At the same time, large portions of Colorado and New Mexico are expected to remain dry, particularly across the central and southern Rockies.
"The high-pressure system that's kind of parked right over the Four Corners states is going to shift eastward, and that should allow for a flow of tropical moisture to come up through Arizona, Utah into the Great Basin," said Brad Rippey, a meteorologist with the U.S. Department of Agriculture.
The monthly outlook builds on recent improvements already seen in parts of Arizona and the Southwest, where monsoon storms have boosted soil moisture and eased some short-term drought conditions, Rippey said.
But those improvements shouldn't be confused with a meaningful recovery for the Colorado River Basin, Dan McEvoy, regional climatologist at the Desert Research Institute and the Western Regional Climate Center, said.
"There's the kind of shorter-term drought conditions that can come and go quicker that affect things like rangeland conditions, soil moisture, vegetation health," he said. "Then there's the long-term drought, which is what's really the big story in the Colorado River Basin."
The distinction matters because the U.S. Drought Monitor captures multiple types of drought. While a wet stretch of summer weather can improve conditions for agriculture and ecosystems, it does little to replenish the large reservoirs that supply water to millions of people across the West, McEvoy said.
This year's outlook comes after a disappointing snow season across much of the Colorado River Basin, where below-average snowpack and an unusually warm spring limited runoff into reservoirs.
"It really does not do a whole lot for the big picture of water supply," McEvoy said. "It does not negate the horrific snowpack year that we had."
Instead, he said, the summer rains are more of a bridge to the next water year than a solution to the basin's long-running water challenges. Rain can also raise the risk of floods and mudslides in canyons or downstream of land burned by wildfires.
Looking ahead, McEvoy said attention will soon shift from the monsoon to the coming winter. Forecasters are closely watching a strengthening El Niño, which could favor wetter conditions across the Southwest, though it's still too early to predict how much snow the region will receive.
This story was produced by the Mountain West News Bureau, a collaboration between KUNR, Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNC in Northern Colorado, KANW in New Mexico, Colorado Public Radio, KJZZ in Arizona and NPR, with additional support from affiliate newsrooms across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting and Eric and Wendy Schmidt.
