The weekend brought frigid temperatures to Long Island with temps not topping 20 degrees and a wind chill below zero, forecasters said. Newsday's Steve Langford reports.  Credit: Kendall Rodriguez; Howard Schnapp; Debbie Egan-Chin; Johnny Milano

Long Islanders can expect cold weather, strong winds, a bit of snow and heavy rain as the region moves into a coastal flood watch late Sunday night.

The weather during the day Sunday is expected to be mild, with highs near 40 and calm winds. That will change Sunday night as a strong storm arrives in the region, according to the National Weather Service.

Rain and snow are likely before 10 p.m. Sunday, after which the snow will be replaced by rain. Little to no snow accumulation is expected on Long Island, but forecasters say up to six inches of snow could be dumped on northeast New Jersey and the Lower Hudson Valley.

Up to 1½ inches of rain is predicted to fall on the region. As the rain moves in, wind speeds are expected to rise from 9 mph to up to 30 mph after midnight Sunday with gusts reaching more than 45 mph. The blustery weather will hang around through Monday, when the weather service predicts wind gusts to reach as high as 50 mph.

The heavy rainfall Sunday night from what the weather service called a "quick-moving" storm could result in flooding. Coastal flooding is expected to be "quite widespread" Monday morning, the weather service said. The flooding paired with high wind speeds Monday morning pose the risk of coastal surges of two to four feet.

Forecasters pinpointed southern Nassau, southwest Suffolk, southeast Suffolk and northeast Suffolk as locations that could face flooding. The flooding is expected to be widespread and can range from moderate to major in certain areas, but depends on wind strength.

Homes and businesses near the waterfront are especially vulnerable, the weather service said. Numerous road closures are possible and vehicles parked near water are at risk of flooding. "Significant" beach erosion is expected from the storm, forecasters predict.

Hempstead Town Supervisor Don Clavin said work crews began preparing several days ago for the severe weather by cleaning storm drains and trimming tree branches. He called on residents to prepare as well. Batteries could prove useful, as the town is expecting some power outages, he said.

"We’re asking residents, get prepared now," he said at a news conference Saturday. "Monday could be a really, really difficult day. If you don’t have to go out, don’t."

Warming centers will be open due to the weather through Monday:

  • Cantiague Park Administration Office — 480 W John St., Hicksville

  • Wantagh Administration Building — 1 King Road, Wantagh

  • Mitchel Field Administration Building — 1 Charles Lindbergh Blvd., Uniondale

  • Dix Hills Ice Rink — 575 Vanderbilt Pkwy., Dix Hills

Temperatures on Monday will be in the high 40s with lows in the mid-20s. There is a chance of rain during the day and a slight chance of snow Monday night. Tuesday and Wednesday are predicted to be clear and chilly.