New York (IP)- A “once-in-a-lifetime” blizzard has killed at least 55 people in the United States, including 25 in western New York’s Erie County, officials said Monday morning.

Iran PressAmerica: The number of deaths from the monstrous storm was expected to grow as snow continued to blanket Erie County, leaving roads in many areas impassable, including the majority of Buffalo, County Executive Mark Poloncarz said at a news conference.

“We can see sort of the light at the end of the tunnel, but this is not the end yet,” Poloncarz said. “We are not there.”

Snow was expected to fall in Erie County into Tuesday afternoon. Nationwide, temperatures plummeted, and substantial snow drifts have trapped people inside their homes and snarled travel.

Stretching from the Great Lakes near Canada to the Rio Grande along the Mexican border, the storm has killed at least 55 people as of Monday morning, according to an NBC News tally. The deaths were recorded in 12 states: Colorado, Illinois, Kansas, Kentucky, Michigan, Missouri, Nebraska, New York, Ohio, Oklahoma, Tennessee, and Wisconsin. 

At least 34 are dead as severe blizzard sweeps across US

The medical examiner’s office in Erie County determined the 25 deaths there to be directly related to the blizzard, Poloncarz said. 

The county executive said a “good portion” of those deaths occurred in Buffalo and that many died from heart problems while shoveling or snow blowing. Others were found dead inside their cars. At least one person in Niagara County was killed from carbon monoxide poisoning, he said.

The ferocity of the storm was unlike any the region has seen, Poloncarz said. 

“It’s a generational storm that, unfortunately, we haven’t begin to really assess its full toll,” he said.

On Monday morning, a “band of heavy lake effect snow” in the Buffalo area was producing 2 to 3 inches of hourly snowfall, with accumulations reaching 6 to 12 inches and as much as 1 to 2 feet for Jefferson and northern Lewis counties, the National Weather Service said in its 6:43 a.m. bulletin.

“Lake effect” occurs when cold air passes over the unfrozen and warmer lake water, causing moisture and warmth being transferring to the lower parts of the atmosphere. The air then rises to form clouds, resulting in intense snowfall.

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