A dense fog advisory is in effect for Long Island until 10 a.m. Monday, the National Weather Service said.
The advisory "means visibilities will frequently be reduced to one-quarter mile or less," the service said.
The weather service urged drivers during the morning commute to slow down, use low beam headlights, "and leave plenty of distance ahead of you in case a sudden stop is needed."
There's a slight chance of showers Monday morning, and a chance of showers and thunderstorms after noon, forecasters said.
Some of those storms "could produce heavy rain," the weather service said. Otherwise it will be mostly cloudy with temperatures in the upper 60s to low 70s.