Colorado helicopters grounded in search and rescue effort

Helicopter crews were grounded Monday thanks to thick clouds, suspending search and rescue operations for more than 1,000 people in Colorado missing due to destructive flooding.

At least seven people have been killed since downpours in the eastern Rocky Mountains left some 1,200 people cut off from aid and communication in Larimer County. Colorado Gov. John Hickenlooper said the helicopters would continue their efforts once clouds lifted.

Two teams of 80 Federal Emergency Management Agency personnel have joined with state rescuers in an attempt to find those stranded by washed out roads.

Hickenlooper said that, while the death toll would likely rise, he was hopeful that most of the 1,200 people would be returned "safe and sound."

Rescuers are urging residents to use white sheets, mirrors, flares and signal fires to help attract the attention of pilots, and to be ready with important personal effects when help arrives.

Almost 15 inches of rain has fallen in affected areas of Colorado since Monday, including four inches just on Sunday. Some National Guardsmen and first responders had to themselves be rescued Sunday when rising waters became too high for their tactical vehicles.