A small craft advisory is in effect Tuesday for Long Island's ocean waters and South Shore bays, the National Weather Service said in its marine forecast.

The service's Upton office said the advisory runs through late Tuesday night and includes from Moriches Inlet to Montauk Point, Fire Island Inlet to Moriches Inlet, Sandy Hook, New Jersey, to Fire Island Inlet and a range out 20 nautical miles for each area.

The advisory also covers South Shore Bays from Jones Inlet through Shinnecock Bay and New York Harbor.

Wind gusts up to 25 knots are to subside only slightly, to about 20 knots, keeping seas at about 5 feet, the service said.

Also, dense fog could develop overnight and linger through Wednesday morning.

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The service said temperatures on the ocean range from 54 degrees at Montauk to 51 degrees west and along the shore.

For Long Island Sound, temperatures are slightly higher.