The Crested Butte News Serving the Gunnison Valley since 1999
“Things are rarely average”
The summer monsoon cycle arrived in the valley last week, dropping rain in areas that hadn’t seen moisture in weeks. After Crested Butte received no measureable rainfall in June, July has seen a start to afternoon thunderstorms that have produced several showers and two days of rain totaling almost an inch.
That’s not unusual, since June is, on average, the driest month of the year and July isn’t far behind, with only about two inches expected. But those two inches are important in a part of the state that gets the short end of the stick when it comes to summer rain.
According to meteorologist and regional weather forecaster Joel Gratz of opensnow.com, winds from the east pushed enough moisture into Colorado over the weekend to drop three inches of rain on Denver, or about 20 percent of the city’s annual precipitation, in less than two hours. And people all across the Front Range experienced a similar deluge.
Unfortunately, as the rainclouds were pushed further west, they were drained of some of their moisture and had little left for Colorado’s Western Slope. Although Crested Butte got only a half-inch of rain from the storm, it was the most significant precipitation event the town had seen since a snowstorm in May.
“Generally the monsoon is a very standard thing to happen in July and early August. It doesn’t mean it’s guaranteed,” Gratz says. “It takes different forms every year and creates different amounts of precipitation. But it’s necessary for a good part of the summer precipitation in a lot of the state.”
According to the Rocky Mountain Biological Laboratory’s website, where weather observations from the Gothic townsite are compiled, the month of July has gradually picked up precipitation this year and recent cloudy days caused a shift in the balance between the amount of moisture falling from the sky and that being stripped from the ground by the wind and sun.
Less than a half-inch of rain fell on Gothic during the entire month of June. And July got off to a dubious start, with just .12 inches of rain falling in the first two weeks, while the wind and sun were estimated to be stripping the soil of at least that much moisture every day.
Rocky Mountain Biological Laboratory business manager billy barr, who has been compiling winter precipitation in the town since 1973 and summer precipitation data since 2001, pointed out that the town of Crested Butte has already gotten more rain for the year than Gothic has, although with the localized nature and intensity of the summer storms, that could change any afternoon.
The amount of rainfall in June and July can also change from year to year, with drier weather persisting the last three years. Over the last 30 years, June has seen an average of 1.2 inches of rain for the month, while the last three years have averaged just five one-hundredths of an inch. This year was the only year since town records began in 1981 that Crested Butte didn’t get any rain in June.
The town has already surpassed the precipitation totals for July from several of the last ten years, with 1.79 inches. The sudden downpour on Monday evening caused the Gunnison River to see a spike in flows of between 50 and 75 cubic feet per second through the evening that muddied the waters from Almont to Blue Mesa.
“Usually the monsoon will tend to peter out in the beginning of August,” Gratz says. “You can only say on average what will happen over the next four to six weeks. But things are rarely average. They’re either a little wetter for a time and then drier. At least over the next week or two we’ll see little surges and breaks in the monsoon but no massive pattern shift.”
