Just two days after they fled a firestorm, residents of two Colorado suburbs that had been gutted by flames slogged back home on Saturday through nearly a foot of snow and single-digit temperatures to confront a new list of woes: frozen pipes and water damage, thanks to an abrupt turn in the weather.

The desperately needed snow arrived too late to save 991 homes that were destroyed as a wildfire fueled by hurricane-force wind gusts roared through parched grasses and into suburban cul-de-sacs in the suburbs of Louisville and Superior, just outside the college town of Boulder.

And in a discouraging reversal, law-enforcement officials announced on Saturday that they were now searching for three people feared dead inside their burned-out homes. Immediately after the fire, officials had said there were no reports of deaths. Now, with snow hindering the search efforts, Sheriff Joe Pelle of Boulder County said the county would bring in cadaver-finding dogs to search for victims.

Potentially there are human remains in those homes,” he said. “It’s not even safe to step into the scene. We don’t know what’s underneath.

Sheriff Pelle said investigators looking into the cause of the fire had served a search warrant after receiving several tips, but he did not offer any additional details. Officials had first suggested power lines as a potential cause, but on Saturday they said they had determined there were no downed electric lines near the fire’s point of origin.

If it turns out to be arson or reckless behavior, we’ll take appropriate actions,” the sheriff said.

Family members identified one of the missing people as Nadine Turnbull, 91, telling 9News that a relative had tried to rescue her from her home in Superior only to be turned back by flames engulfing the front and back doors.

As thousands of surviving homes remained without power and gas on Saturday, the seven-degree temperatures and the 10 inches of snow that fell on the Boulder area touched off a frantic new battle against the weather. It came as President Biden approved a disaster declaration for the fire zone, opening up new sources of federal aid.

Residents hiked into their neighborhoods to drain their pipes and empty hot-water tanks. They scrambled to set up space heaters. People on vacation hundreds of miles away pleaded for help in shutting off the water at their homes and opening up their taps to prevent a flood.

Nearly 13,000 households around Boulder were without natural gas on Saturday, and 7,500 households still had no power, according to Xcel Energy, the local provider. The company said that electricity would be restored later on Saturday but that natural gas would take several days.

The Town of Superior said it was shutting off water in the fire zone on Saturday to prevent additional damage.

This is disappointment on disappointment,” said Alli Bowdey, a nurse whose family fled its Louisville home and was packed into a house with relatives. On top of everything else, her husband tested positive for the coronavirus and was isolating in a hotel on Saturday.