By Keith Coffman

DENVER (Reuters) - Soaring temperatures and recent rains have hastened the run-off from Colorado’s melting snowpack, causing widespread flooding concerns across the Rocky Mountain state, authorities said on Tuesday.

The National Weather Service has issued flood warnings or advisories for more than a dozen counties, ranging from engorged mountain streams to downstream rivers and tributaries on the high plains of eastern Colorado.

Temperatures reached the low 90s on Tuesday in the east of the state, and waters from the melting snow are roaring down the mountainsides.

Snowpack totals in Colorado’s eight river basins are 193 percent of the average this season, according to the federal government’s National Resources Conservation Service.

In Greeley, 50 miles (30 km) northeast of Denver, the Cache La Poudre River is at near-record levels, said Chad Gimmestad, a meteorologist with the National Weather Service.

The river has crested at nine feet, Gimmestad said. Flood stage is considered to be eight feet.

"We're still in the thick of the run-off," he said.

Ten homes and businesses in Greeley have sustained "major damage" from the flooding and eight streets have been closed due to the high water, city officials said in a statement.

"Residents in flood prone areas are asked to maintain a heightened level of awareness and stay clear of floodwaters and river banks," the city warned.

All of Weld County, where Greeley is situated, is under a flood warning for the next three days.

A 14-year-old boy and his 38-year-old uncle drowned in the fast-moving Cache La Poudre on Memorial Day in late May, prompting officials to warn people of the threat from rushing waters.

In mountain communities, "some rivers continue running high with water spilling into low-lying areas," the weather service said in an advisory.

Some flooding has been reported in the northwest of the state at the confluence of the Elk and Yampa rivers in Routt County.


(Editing by Daniel Wallis and Paul Tait)