Despite a modest amount of rainfall in Southwest Colorado over the past few weeks, weather observers say there has been no sign of a typical monsoon pattern settling into the region.
“We’ve seen monsoon-like behavior,” said Brian Moyer, meteorologist for the National Weather Service in Grand Junction. “But we haven’t had that direct tap into sub-tropical (storm systems) that produce a lot of rain over our area.”
A devastatingly low snowpack last winter in the San Juan Mountains and nonexistent spring rains set the stage for one of the driest and hottest years in recorded history for Southwest Colorado.
As a result, since the spring, Southwest Colorado has been listed in an “exceptional drought,” the highest and most intense category of drought, according to the U.S. Drought Monitor.
These dry conditions led to a shorter ski season, reservoirs running low on storage, rivers drying up too soon and perhaps the most visible impact, fire danger, which materialized with the outbreak of the 416 and Burro fires.
So it was with some relief in May that the Weather Service’s Climate Prediction Center forecast a higher probability of above-average rainfall over the summer months into September.
But that prediction, for Southwest Colorado at least, has not panned out.
Since June 1, a weather station at Durango-La Plata County Airport has recorded just 1.72 inches of rainfall, down nearly half of the average rainfall of 3.09 inches.
The drought has taken a massive toll on the region’s reservoirs.
Lemon Reservoir along the Florida River, which has the capacity for 40,000 acre-feet, was 16 percent full as of Friday. Vallecito Reservoir on the Pine River, with a capacity for 125,400 acre-feet, was just 20 percent full.
Fire danger, too, is still a very real risk, said Richard Bustamante, San Juan National Forest fire management officer.
“The rain we have received gave us some relief, but now we’re starting to have a second fire season and we’re staying pretty active,” he said.
Within the past two weeks, local firefighting agencies have responded to nearly 60 reports of fire starts, Bustamante said. One fire, the Plateau Fire near Dolores, has grown to more than 10,000 acres.
“Obviously this year, we’re still recovering from a long-term drought,” Bustamante said. “But there is an end in sight, it’s just a slow transition.”
Matthew Rosencrans, a meteorologist for the Climate Prediction Center, said that in May, weather models forecast an early arrival of the monsoon pattern, which brings an uptick in moisture to the Southwest.
And it has – just not for Southwest Colorado.
Arizona and New Mexico have actually recorded above-average rainfall, Rosencrans said, especially in areas around the Santa Fe National Forest in New Mexico and Flagstaff, Arizona.
“But as you’ve noticed, it’s not really working out for Southwest Colorado,” he said. “You guys are missing out on the monsoon rainfall.”
Over the past few months, a high-pressure system – which is inhibiting the formation of rainstorms – has been sitting over the northwestern United States, extending through the Great Basin in Nevada to Southwest Colorado.
During the summer, this high-pressure system usually recedes back to the Northwest, clearing the way for storms to move across Southwest Colorado. That hasn’t happened this year, Rosencrans said.
“You guys are trapped right in the middle between those two primary areas of activity with dry weather to the north-northwest and wet weather to the south-southwest,” he said.
The Climate Prediction Center still holds a rosy view for Southwest Colorado over the next several months. It’s expected the El Niño weather pattern and the moisture associated with it will kick in during that time.
In the short term, Moyer said storms will track across Southwest Colorado over the weekend.
These storms are a result of what happens on a usual day in the region – the ground heats up, causing air to rise and the formation of clouds. With more moisture in the atmosphere, there’s a better chance of rain.
“I wouldn’t get excited, because you’re not going to see anything substantial,” he said.
Moyer said in the six years he’s been tracking weather in Southwest Colorado, he can’t recall a summer without a monsoon. It’s unclear when weather patterns, which are driven by global weather, will change.
“We still have August and September to go,” Moyer said. “So we’re not shutting the door on it yet.”
jromeo@durangoherald.com
