BUFFALO - As temperatures near Buffalo, N.Y., rose above freezing on Saturday, volunteers fanned out to help their neighbours clear the walls of snow that have paralyzed parts of the region this week, but the warming trend also raised the threat of flooding.

More than 200 volunteers, called the Shovel Brigade Mob, armed themselves with shovels and headed into neighbourhoods south of downtown Buffalo. The group said some residents were still stuck in their homes, days after a lake-effect system clobbered the region with up to seven feet of snow.

"Everyone wanted to do something for those who are stuck and stranded who don't have groceries and diapers," said Sara Heidinger, a volunteer co-ordinator.

The massive snowfall, combined with forecasts of rain, raised fears that the roofs of homes and businesses could collapse under the weight, adding urgency to clearing efforts.

The system, dubbed the "Knife Storm," dumped about seven feet (2 metres) of snow in parts of western New York over a three-day period while leaving other areas virtually unscathed, cutting the city in half, Heidinger said.

"From where I am standing I can drive 10 minutes south on completely cleared roads and then hit where it is a disaster," she said.

South Buffalo resident Christopher Orazio, 22, said he and his girlfriend have been cooped up in their home, blanketed by massive piles of snow, for several days.

"We are just watching TV and watching the news, we are both hungry and fighting with each other," said Orazio, adding that the couple has been eating small cans of soup and noodles.

As the city dug itself out on Saturday, concerns about widespread flooding grew as temperatures rose. The National Weather Service issued a flood watch, predicted rain and forecasted temperatures above 50 degrees Fahrenheit in parts of the region for the next few days.

During a press conference on Friday, New York Gov. Andrew Cuomo said an operation was underway to stockpile western New York with boats, helicopters, pumps and sandbags to battle the flooding.

"Prepare for the worst and hope for the best, and that is what we are doing," he said.

Despite the conditions, Heidinger said a regular sight has been people pulling beer in their sleds and carrying pizza boxes from a local pizzeria that had just reopened its doors in downtown Buffalo.

"There's this fun attitude of people just toughing it out and making the best of what they have," she said.