NEW YORK - A second monster storm in a week roared into the U.S.’ northeast region, cancelling flights, closing schools and shuttering many businesses.

The storm was blamed for cancellation of more than 5,400 flights and forced delay of the jury selection in the trial of Boston Marathon bombing suspect Dzhokhar Tsarnaev.

In Boston, Mayor Marty Walsh must have plenty of faith in his snow removal teams. The storm blasted eastward after challenging records in the Midwest. The 16.7 inches that fell in Detroit made it the Motor City’s biggest snowstorm in 40 years, and the third-biggest snowstorm on record in the city, according to the National Weather Service.

In Chicago, the 19.3 inches made it the Windy City’s fifth-biggest snowstorm on record.

The weather system moved slowly eastward overnight into Pennsylvania and western New York state. It then proceeded to New England, where residents barely had time to celebrate their team’s m Super Bowl victory before once again breaking out the shovels and snowblowers.

Less than a week ago, Bostonians were digging out from 2 feet of snow following one of the biggest snowstorms in the history of a city used to plenty of winter weather. The 34.5 inches that fell in Worcester, Mass., made last week’s snowstorm the biggest in that city’s history.

Round two rolled into the region Monday, with 9 to 15 inches forecast for Boston and nearly as much headed for Hartford, Connecticut, Providence, southern New Hampshire and Vermont, the National Weather Service said.

The heaviest snowfall is expected throughout the day Monday before the system makes its way to the Atlantic Ocean early Tuesday.

In the New York City metro area, freezing rain was leading to concerns for a flash freeze later Monday as temperatures plummet down into the 20s, the weather service warned. Driving conditions were hazardous

Four people are known to have died in snowy weather Sunday.

Ohio officials said a Toledo police officer died of an apparent heart attack while shoveling snow in his driveway and the city’s 70-year-old mayor was hospitalized after he had a heart attack and his SUV crashed into a pole while he was out checking road conditions.