From KUNC (Alex Hager):
Growers in the West have persisted through the ups and downs of dry years for a long time, but a two-decades-long trend of drought in the region is now entrenching itself with no clear end in sight.
This year is unlikely to bring any major relief.
Forecasters say this winter will be shaped by “La Niña,” a weather phenomenon during which cold water off the Pacific coast alters temperature and precipitation patterns over the Western U.S. Its effects are hardly guaranteed, but typically mean a colder, wetter winter for the northwestern portion of the country, and a warmer, drier winter in the Southwest. The dividing line often falls in the middle of Colorado.
“In general it means towards the northern mountains would be more likely to have a better winter season and the southern mountains — the San Juan Mountains, the Sangre de Cristos — might not be able to get as much,” said Becky Bolinger, assistant state climatologist at Colorado State University.
She cautioned that weather is hard to predict with a high degree of certainty, describing the area’s erratic patterns as “a crapshoot,” but historical records suggest it will likely leave the Colorado River basin warmer and drier than normal this coming winter.
“While we do depend on the (summer) monsoon season,” Bolinger said, “especially to help fill up those soils before we enter the cold season, we really need that snowpack to kind of really dig out like Arizona did with its monsoon season.”
Bolinger was alluding to this year’s historically wet summer in Arizona — where parts of a state with millions of Colorado River water users were drenched with record-setting rain totals. Tucson, for example, saw its wettest calendar year in recorded history. July was the state’s second-wettest month of all time…
And in the grand scheme of the Colorado River basin, wet seasons in Arizona are literally a drop in the bucket. Before going on to feed farms and taps all the way down to Mexico, the majority of the river’s water starts as rain and snow high in the mountains of Wyoming and Colorado. In the long term, Bolinger says climate change will bring shorter winters, warmer temperatures and drier soil…
Turning things around in the Colorado River basin and bringing more water to the people who depend on it will take years of above-average rain and snow where it matters most.