World and Nation

More rain expected in as Colorado as rescuers wait for fog to clear out

DENVER — As rain continued to fall Monday along Colorado’s Front Range, officials waited for a clearing in the weather so National Guard helicopters grounded by rain and fog could resume searching for hundreds of people who remain cut off by floodwaters.

Officials said that they had not yet determined when the helicopter rescue flights could proceed, but the authorities have told residents isolated in Lyons, Jamestown and other mountain towns that once the helicopters were in the air that they should do what was necessary, within reason, to get the attention of the National Guard pilots. Among the suggested methods were to wave or place a white sheet on the roof of their house, light signal flares or small fires, or redirect the sun with mirrors.

Residents needing evacuation were also asked to pack medicine or clothes they might need because it could be days or weeks before they are allowed to return home.

Telephone landlines, cellphone service and the Internet have either been knocked out in the area or are undependable. Given the risk of further mudslides and the amount of mud, water and debris that have piled up in some places, even walking a few feet can prove difficult, officials said.

The rain, which has been falling on the Front Range for much of the past week, prompted fears of new flooding Monday. The National Weather Service issued a flash flood watch starting Monday afternoon and extending into the early evening hours in anticipation of heavy thunderstorms expected to roll through the area. Some of the storms could bring as much as 1 inch of rain in as little as 30 minutes, the weather service said in an advisory.

The storms have left at least six people dead or presumed dead, the most recent reported fatality being that of an 80-year-old woman who was apparently washed away with her home.

More than 800 people are now listed as “unaccounted for” in Larimer and Boulder counties, the authorities said. Officials said they hoped that most of those people had simply been unable to reach friends and family members because normal lines of communication, including mobile phone service, remained undependable.

On Sunday, National Guard pilots waited all day for the fog to lift, but were unable to get off the ground.

“The good news is we’ve got 16 helicopters,” said John Schulz, a spokesman for the sheriff’s office in Larimer County. “The bad news is they can’t go anywhere.”