NEW YORK — Parts of the northeast were bracing for a stormy night Sunday, with high winds and heavy rains bringing threats of flooding and power outages through the Monday morning commute.

Flood watches were in effect in New York, New Jersey, Connecticut and southern New England through Monday. The National Weather Service said 3 to 5 inches of rain was expected across parts of Long Island and southern Connecticut, with other areas in line for 2 to 3 inches.

Wind gusts of up to 50 mph were forecast, including in New York City, where the Metropolitan Transportation Authority announced a ban on empty tractor-trailers and tandem trucks for 12 hours beginning at 6 p.m. Sunday.

New York Mayor Eric Adams activated the city’s flash flood emergency plan.

“We’re preparing for heaviest rains and strongest winds Sunday night into Monday morning, which means everyone should take the necessary precautions to protect themselves and their belongings in the event of potential flooding conditions in low lying areas,” he said during a radio broadcast Sunday. “So, this is some serious stuff.”

New York Gov. Kathy Hochul said state agencies were standing by with generators, portable heaters, chainsaws and other equipment.