A strong monsoon has lowered the short-term drought designation for Southwest Colorado, but the region remains stuck in a long-term drought.
The top half of La Plata County and the northeast corner of Montezuma County have improved from severe drought, listed as D-2, to moderate drought, or D-1, according to the latest map from the U.S. Drought Monitor.
The bulk of both counties, however, remain in extreme drought, D-3, with the southwest corner of Montezuma County still listed in exceptional drought, D-4, which is the most severe drought status given by the U.S. Drought Monitor.
Brad Rippey, a U.S. Department of Agriculture meteorologist with the U.S. Drought Monitor, said, “What we see right now in southwestern Colorado is that we're seeing these longer-term indicators, still pointing to the D-2s and D-3s, even a couple of D-4s. Whereas your short-term indicators, if you just look at the last 30 days, we’re actually on the wet side of things.”
The monsoon has allowed the U.S. Drought Monitor to drop the short-term drought status for Southwest Colorado, but the region remains listed in a long-term drought, Rippey said.
“You have to kind of balance the long- and the short-term,” Rippey said.
When new maps are issued by the Drought Monitor, Rippey said, several factors are examined including precipitation measurements, soil moisture, stream flows and vegetation health, among dozens of other factors.
The data is also examined against historical patterns to determine drought status, he said.
“What we like to see is a convergence of evidence,” he said. “In a perfect world, everything would point to the same drought intensity. Of course, in real life, it’s never that easy.”
Rippey said it would take a couple of good seasons, including above-average snowpack this winter and another good monsoon season next year “to put a dent in the longer-term drought.”
“There still are some very serious long-term issues,” he said. “If you start looking at reservoirs, groundwater, even some of the stream flow hasn’t fully bounced back, you’ll see the region still has long-term issues, and it’s not going to go away with one robust monsoon season.”
National Weather Service meteorologist Erin Walter said beginning Wednesday, Southwest Colorado will be in a drying trend through the remainder of the week into early next week.
“Conditions will dry out. It looks like Thursday might be the driest part of the week,” she said.
A high-pressure system is building over Nevada and western Utah, and that will prevent the southerly winds that have been bringing monsoonal rains.
Still, a slight chance of rain will remain this week, principally in higher elevations, Walter said.
The high-pressure system blocking the monsoonal pattern is expected to break down early next week, possibly on Tuesday. Walter said that should allow for the resumption of southerly winds and a return to monsoonal conditions.
“We’ll be drying out a bit, but it doesn’t mean the monsoons are ending,” she said. “Next week, it’s looking like a good chance the monsoons will return, so this looks more like a break rather than an end to the monsoons.”
If the monsoon season remains robust, rains could be in the forecast through early September.
Rippey said autumn is usually a period where precipitation drops before snows begin in November.
After the monsoon, the U.S. Drought Monitor will begin examining snowpack, with a base usually forming in November in Southwest Colorado’s mountains.
The snowpack will be key in allowing the U.S. Drought Monitor to upgrade long-term drought conditions through winter.