Areas across the Northeast were under flash flood and high wind warnings early Monday as a massive storm, which rattled Middle Tennessee with a string of deadly tornadoes over the weekend, moved through the region.

Power outages were reported in New York, Connecticut, Massachusetts and Maine as winds knocked down trees and power lines. Roads flooded by the barrage of rainfall or blocked by debris have caused back ups, detours and street closures ahead of rush hour traffic. Over 125 flights were delayed and 13 were canceled on Monday at airports in New York, Washington D.C. and Boston, according to FlightAware.

Wind gusts of up to 40 mph were recorded in New York City and Boston. Meteorologists said gusts in some areas, such as Long Island and the southern coast of Massachusetts, could reach 60-70 mph before the storm slowly moves off the Atlantic coast by Monday afternoon.

The storm brought the first snowfall to Washington D.C. this year, with amounts ranging between 0.2 to 1 inch, before the system moved east out of the area around 7 a.m. Parts of Maryland recorded up to 3 inches. Several schools delayed their start time by two hours on Monday because of the snow.

Cold air moving behind the front was forecast to bring heavy snow over the northern Appalachians and interior Northeast, according to the weather service. A lake-effect snow was expected to develop over parts of the Great Lakes into Tuesday as well.

The weather comes after the greater Nashville region was pummeled by an estimated 13 tornadoes late Saturday. Six people were confirmed dead Saturday night in Tennessee, and 83 were reportedly taken to hospitals, according to officials.

Developments:

∎ The Metropolitan Nashville Police Department identified three people, including a 2-year-old boy, who were killed in storms in Nashville on Saturday. Joseph Dalton, 37, was inside his mobile home when the storm rolled it on top of the home of Floridema Gabriel Perez, 31, according to police. Both died. Perez's son Anthony Elmer Mendez, 2, was also killed.

∎ Three other fatalities were confirmed in Clarksville by the Montgomery County Mayor's Office Saturday evening. Montgomery County officials also said 23 people are being treated at hospitals for injuries.

Cleanup underway in Tennessee as tens of thousands without power

A coordinated cleanup effort in areas where extensive tornado damage occurred in Tennessee began Monday, with volunteers being taken to devastated areas on buses.

The deadly storm system and tornadoes sent dozens of people to the hospital, damaged buildings, turned over vehicles and knocked out power to tens of thousands. As of Monday morning, over 15,000 people were without power, according to figures from CDE Lightband and Nashville Electric Service.

The National Weather Service said an estimated nine counties were impacted by tornado damage and counties affected by severe weather damage were "likely double" that.

Nine of those hospitalized were transferred to Vanderbilt University Medical Center and were in critical, unstable condition on Sunday, according to the Tennessean, part of the USA TODAY network.

"Our community is strong and our faith is strong," Montgomery County Mayor Wes Golden said on Sunday morning, holding back tears.  "We will get through this together. Please pray for all of those involved."

Contributing: The Tennessean; The Associated Press