More than 80 million people in the US are under some form of winter watch or warning, according to <i>USA Today</i>, as a major snowstorm rolled through the north-eastern US on Monday. The multi-day storm resulted in snow accumulation in Chicago and Washington, DC, on Sunday before it moved into Philadelphia and New York City. The storm is expected to last through Tuesday. New York City, the most populous city in the US, may see somewhere between 16 and 24 inches of snow, according to the National Weather Service. Tri-state area bus and train travel between New York, New Jersey and Connecticut is suspended for several hours on Monday. FlightAware also recorded thousands of cancelled flights. "This storm is no joke and the main concern right now is that the expected snowfall rate of two inches per hour this afternoon creates an extremely dangerous situation on our roadways," New York Governor Andrew Cuomo said on Monday. He issued a state of emergency for New York City, Long Island and Hudson Valley, to the north of the city. Non-essential vehicular travel was prohibited in New York City through Monday, when the area will see intensified snow accumulation and wind gusts. New York City Mayor Bill de Blasio shared similar warnings on Sunday night. “This is not a storm to underestimate,” he said during a news briefing. “Take it seriously. This is a dangerous storm.” If forecasts hold, the storm could rank in the top ten biggest snowfalls in New York City's history. The unique timing of the storm has snarled up how the area is responding to the pandemic. Mr de Blasio made the decision to cancel Covid-19 vaccinations for Monday and Tuesday, but said they would resume on Wednesday. "Last thing we want to do is to urge our seniors to come out in the middle of a storm like this," he said. "It doesn't make sense." The state of New Jersey has also shut down its major vaccination sites as a result of the storm. The largest public healthcare system in the US, NYC Health + Hospitals, also moved to suspend Covid-19 testing on Monday and Tuesday.