Colorado’s monsoons are spotty at best so far this summer, according to meteorologists and climate experts.
When afternoon thunderstorms start rolling through the state in late summer, Coloradans start talking about monsoons. The summer showers can be critical for farmers and ranchers in drier years when drought conditions are expanding. But if these thunderstorms come with more lightning than rain, they can increase the risk of wildfires like the five currently burning on the Western Slope.
This year’s monsoons seems to be sputtering into gear in eastern Colorado, but western Colorado is parched.
“At this point it looks like we’ll still have a fairly active monsoon,” said Zach Hiris, a meteorologist for the National Weather Service in Boulder who focuses on north-central and northeastern Colorado. “But if we’re hoping for it to wipe out the drought across western Colorado, I think that’s going to be difficult.”
Colorado’s monsoons can span June to September, but it varies from year to year and across regions. The storms are part of the North American Monsoon, a shift in the wind pattern that allows for moisture to flow from the Gulf of California or other coastal areas into the Southwest, according to the Colorado Climate Center.
In eastern Colorado, conditions have been fairly normal over the past 30 days, and the summer storms have been more prevalent, climate and weather experts said.
The Front Range and northeastern Colorado have seen some storms this week, Hiris said. Looking ahead, both regions have a chance of storms and cooler temperatures (in the low- to mid-80s) in store for the next few days before warmer temperatures and drier conditions return over the weekend and into next week. More storms could roll through toward the end of July, he said.
Overall, Colorado has been “pretty darn dry” for July, Hiris said.
Denver International Airport, for example, has seen 0.62 inches of rain in July, which is about 40% of the average from 1995 to 2020. Since Oct. 1, the Denver area has had 11.09 inches of rain, which is slightly above the median from 1991 to 2020.
In western Colorado, the dry spell has continued after a winter with lower-than-usual snowpack. Surges of monsoonal moisture have mostly missed western Colorado to this point, said Peter Goble, assistant state climatologist at Colorado State University’s Colorado Climate Center.
Some areas have seen 30% to 50% of their normal rainfall over the past 30 days. It’s not that the monsoon has been entirely absent in the Southwest. Some areas of eastern and central New Mexico into eastern Colorado have had a stronger monsoons, Goble said.
“There’s been haves and have-nots, which is very normal for this time of year,” he said.
Just because the monsoons can sometimes start in June, that doesn’t mean you can just flip a switch and the monsoon is here, said Dennis Phillips, a National Weather Service meteorologist for western Colorado.
Grand Junction has had 0.17 inches of rain so far in July, which is about a quarter-inch below normal, Phillips said. Durango in southwestern Colorado has received 0.15 inches of rain this month, which is almost two-thirds of an inch less than the 30-year norm.
This week, drier conditions are continuing into the weekend, but by the middle of next week, the chance of rainfall is better, Phillips said.
“We’ll be concerned about the hot, windy conditions,” Phillips said. “If you have fires going, that is not ever a good thing.”
Lightning strikes can spark wildfires, which then spread in windy storms.
Five major fires are burning in Colorado. Of those, four were caused by lightning: the Sowbelly fire in Montrose, Delta and Mesa counties; the South Rim fire in the Black Canyon of the Gunnison National Park in Montrose County; and Turner Gulch and the Wright Draw fires, both in Mesa County. The cause of the Deer Creek fire on the Utah-Colorado border is still under investigation.
Drought is clinging to parts of western Colorado and expanding in the northwestern region, according to the U.S. Drought Monitor.
Parts of the state have experienced abnormally dry or drought conditions since July 2023 when, for a few weeks, Colorado was drought-free. Since May 1, about 40% of the state has been in drought.
Drought conditions improved in eastern Colorado this summer, from dry and moderate drought conditions in early May to mostly drought-free conditions as of July 15. Under moderate drought, crops can experience some damage, streams are lower, and some water shortages can happen.
The state’s more serious drought conditions, dubbed severe and extreme drought by the Drought Monitor, have mostly been in western Colorado.
Northwestern Colorado dipped further into drought over the summer, from unusually dry conditions in May into moderate to extreme conditions by July 15. Extreme drought conditions have held firm in parts of Mesa, Montrose and Delta counties, the location of several wildfires, since early May.
In extreme drought conditions, farmers and ranchers can experience major crop or pasture losses, and other water users might see widespread shortages or restrictions, according to the U.S. Drought Monitor. The national drought map pulls information from local experts, impact reports and conditions observations to assess drought conditions.
No part of the state was in the worst drought category, exceptional drought, as of mid-July.
The state still has quite a bit of summer left to try to get more rainfall, Phillips said.
“I see some hope here in the next week,” he said. “If we keep getting those (storms), maybe we can salvage this monsoon season.”
