BUFFALO, New York (AP) — Residents of the New York state city of Buffalo started digging out Wednesday from a massive snowstorm blamed for seven deaths, even as another headed their way, threatening to break snowfall records.

Homeowners opened their front doors to find themselves sealed in by sheer walls of white. People were marooned at homes, on roads and at work. A woman gave birth in a firehouse after the snow prevented her from reaching the hospital.

Even for Buffalo, a city used to big blizzards blowing in from Lake Erie, this was an epic snowfall. The region found itself buried under up to 5.5 feet (1.68 meters) of snow Wednesday, with another storm expected to bring up to 3 more feet (1 meter) by late Thursday.

"This is an historic event. When all is said and done, this snowstorm will break all sorts of records," Gov. Andrew Cuomo said.

Cuomo warned that a weekend warm-up could lead to significant flooding when the thick blanket of snow melts. Forecasters say rain is possible this weekend.

The storm trapped more than 100 vehicles along a 132-mile (212-kilometer) stretch of the New York State Thruway, the state's main highway that remained closed Wednesday.

Trapped on a team bus for nearly 30 hours, the Niagara University women's basketball team melted snow for water, posed with long faces for pictures that were posted online and tried to keep each other's spirits up.

Bethany Hojnacki went into labor at the height of the storm and ended up giving birth in a Buffalo fire station after she and her husband couldn't get to the hospital. Baby Lucy weighed in at 6 pounds, 2 ounces (3.3 kilograms). Mother and child were later taken to the hospital in an ambulance.

Cuomo said Wednesday afternoon that all the trapped travelers had been removed from their cars.

Asked by reporters how officials could allow people to be snowbound in cars for 24 hours, Cuomo cited a disabled trailer that prevented plows from removing fast-falling snow, and drivers' own wrongheaded choices to drive on a closed interstate highway.

The governor said it would take four or five days to clean up from the storm, which was being blamed for at least seven deaths; at least four of those were attributed to heart attacks.

The one-week snow totals for the Buffalo area was expected to approach the average snowfall for an entire year: close to 8 feet (2.4 meters).

The snowfall was approaching the heaviest 24-hour snowfall on record in the mainland U.S.: 75.8 inches (192 centimeters), which fell at Silver Lake, Colorado, in 1921, weather historians said.

The storm struck Buffalo on a day when temperatures dropped to freezing or below in all 50 U.S. states.