Monsoon outlook still uncertain
By Summit Voice
SUMMIT COUNTY — A few passing thunderstorms over parts of the High Country this past week didn’t do much to alleviate statewide drought conditions, as continued warm and dry conditions prompted federal and state weather watchers to expand drought designations in the state.
As of June 29, almost half the state (46 percent) was classified as being in extreme drought, with almost all the rest of the state under severe drought conditions.
Temperatures running up to 10 degrees above average means moisture is evaporating from soils far faster than it’s building up, and all major reservoirs have dropped below average levels for this date.
Nationally, drought conditions reached a dubious milestone, with 72.01 percent of the contiguous 48 states classified as abnormally dry, the most widespread drought conditions on record.
Streamflow gages in the Colorado River Basin tell the story. None of the measuring stations are reporting above average readings, while 69 percent of the gages are reporting below and well-below average flows.
Most gages on the Yampa, Colorado, Gunnison, Dolores and San Juan rivers are recording flows ranking in the lowest 10th percentile on record. The lowest flows are in the headwaters region on the east end of the Colorado River Basin, according to the June 26 update from the National Integrated Drought Information System.
Flows on key gages in the system, low to begin with, saw big drops in the past week, registering some of the lowest readings on record.
Temperatures have been running between 4 to 8 degrees above average in the southwestern corner of the state and 8 to 10 degrees above average across the rest of the state.
At those temperatures, between .3 and .5 inches of moisture can evaporate per day, meaning that any small amounts of rain that fall offer only very short-lived temporary relief. Simply put, evaporation is far outpacing precipitation, which means conditions are getting drier.
All major reservoirs saw water levels drop during the past week, and while storage was one of the brighter spots in the Colorado water picture the past few months, that is quickly changing, as all Colorado Reservoirs have now dropped slightly below average for this time of year.
Parts of southwest Colorado could see a return of a moist monsoonal flow early in the week, but that forecast is far from certain.
The drought monitor index may get worse before it gets better, as the official recommendation is to elevate drought conditions to severe and extreme across nearly the entire state next week if it doesn’t rain.
The Northwest part of the state could be put in the highest category, exceptional drought.