A slow-moving coastal storm was drenching the Mid-Atlantic early Monday, washing out roads, knocking out power and snarling travel. It was expected to bring heavy rain to New York City and the surrounding region on Monday as officials warned of potential flooding and power outages.

Here’s what to know about the storm:

• Coastal flood warnings were in place through the evening for New York City, Long Island and southern Westchester County, the National Weather Service said. Wind gusts of up to 60 m.p.h. were forecast along the coastal areas of Long Island and at the Jersey Shore.

• New York City is predicted to record half an inch to one inch of rain into Monday afternoon, and one to two inches is expected for eastern Connecticut and Long Island.

• The storm is expected to move through New England by Tuesday, bringing more rain, gusty winds and possible coastal flooding.

• Gov. Kathy Hochul of New York declared a state of emergency on Sunday for New York City and the surrounding counties in preparation for the storm. A state of emergency was declared for all of New Jersey on Saturday.

• The Delaware National Guard was activated on Sunday in case of damage from potential flooding or high winds in the state, the Delaware Emergency Management Agency said.

The storm drenched much of the East Coast over the weekend with heavy rain, strong wind and coastal flooding. Winds and waves battered the Carolinas as oceanfront residents were urged to protect their homes. In South Carolina, some people had to be rescued from their cars as waters overwhelmed roads and swept into buildings, The Post and Courier reported. More than seven inches of rain fell in the last 48 hours in Williamsburg County, S.C., according to the U.S. Geographical Survey.

In New York, utility companies added more than 1,600 workers in the Hudson Valley, Long Island and New York City to respond to the storm, the governor’s office said. Early Monday, wind reached 50 m.p.h. in the New York City area, with the strongest along Long Island.

The New York State Division of Homeland Security and Emergency Services urged residents with aboveground power lines to prepare for outages Monday morning.

New York’s 81st annual Columbus Day Parade, scheduled for Monday, was canceled because of the state of emergency, the Columbus Citizens Foundation said in a statement posted on social media.

NJ Transit suspended parts of its rail service Sunday afternoon through the end of Monday because of heavy rain and high winds. Videos of parts of New Jersey posted on social media showed streets submerged and water rising up the steps of homes.

More than 50 flights in and out of Boston Logan International Airport had been canceled on Monday as of 7 a.m.

Nazaneen Ghaffar contributed reporting.