A small craft advisory is in effect for South Shore waters Monday evening through Tuesday afternoon, the National Weather Service said in its marine forecast.
The advisory covers Moriches Inlet to Montauk Point, Fire Island Inlet to Moriches Inlet and Sandy Hook, New Jersey, to Fire Island Inlet and out 20 nautical miles from each area, said the service's Upton office.
The advisory does not include New York Harbor and Long Island Sound.
A southwesterly flow will persist across the forecast waters Monday and Monday night, as "high pressure over the northern Atlantic drifts east," the service said.
Seas will build to small craft levels Monday night as swells pass to the south and east. Some wind gusts may approach 25 knots.
Weather conditions inland across Nassau and Suffolk counties is expected to be in the mid to upper 70s Monday with south winds from 8 to 14 mph.