The Buffalo area found itself buried under as much as 5 1/2 feet of snow Wednesday, with another lake-effect storm expected to bring an average of 2 more feet by late Thursday.
"This is an historic event. When all is said and done, this snowstorm will break all sorts of records, and that's saying something in Buffalo," Cuomo said.
The storm came in so fast and furious over Lake Erie early Tuesday it trapped more than 100 vehicles along a 132-mile stretch of the New York State Thruway that remained closed Wednesday.
Tom Wilson, of West Seneca, split a Salisbury steak frozen dinner with co-workers and tried his best to get some rest when he was stuck 36 hours at his warehouse job.
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"I slept on a pallet. Then I slept on some office chairs, and then I went back to the pallet," he said. "Then I found some sponges to lay on. I found one pack of sponges unopened. That looks like a pillow to me."
"We tried to make popcorn with a two-by-four, two empty pop kegs, some charcoal and a dust pan," he added. "It didn't work."
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. Mother and daughter were later taken to the hospital in an ambulance.
Cuomo said Wednesday afternoon that all trapped travelers had been removed from their cars, though some truckers were staying with their rigs.
Asked by reporters how officials could allow people to be snowbound in cars for 24 hours, Cuomo cited a jackknifed trailer that prevented plows from removing fast-falling snow, and drivers' own wrongheaded choices.
"What happened was, even though the Thruway was officially closed, people went on. We didn't immediately block every entrance. It was a mistake," Cuomo said.
"Part of it is citizen responsibility," he added. "If the road is closed, it's closed."
The storm was blamed for up to seven deaths in western New York, at least four of them from heart attacks. Erie County officials said a 46-year-old man was discovered in his car, which was in a ditch and buried in snow 24 miles east of Buffalo. It was unclear how he died.
Sunny skies returned to some hard-hit areas Wednesday, but workers were still trying to cart off the acres of snow. Lake-effect snow fell heavily on some northern New York areas east of Lake Ontario.
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With an additional 2 feet possible on Thursday, the one-week totals for the Buffalo area will approach the average snowfall for an entire year: 93.6 inches, or close to 8 feet.
The highest snowfall total for the Buffalo area this time was 65 inches, recorded in Cheektowaga. National Weather Service meteorologist David Church said forecasters haven't determined yet how this storm ranks, but that 60 to 70 inches in 24 hours is probably in the top 5 for the region.
The heaviest 24-hour snowfall on record in the Lower 48 states is 75.8 inches, which fell at Silver Lake, Colorado, in 1921, according to the government.
The governor said it would take four or five days to clean up.
Amtrak passenger train service between Albany and the Buffalo area was suspended. Some of it will resume on Thursday. Mail delivery was interrupted in certain communities with driving bans.
The storm struck Buffalo on a day when temperatures dropped to freezing or below in all 50 states. At least a foot of fresh snow was expected in parts of Michigan through Friday, adding to deep snow on the ground.