That dense fog will affect the evening rush-hour commute on Thursday and perhaps the Friday morning drive as well, the weather service warned.
The warning is in effect in all of southern Connecticut, the lower Hudson Valley, northeast New Jersey and on Long Island, creating dreary, gray conditions.
Dense fog can create a visibility of a quarter mile or less. The warning means the fog will continue into the afternoon, evening and overnight, especially along the coast, the National Weather Service said.
High temperatures Thursday will reach the mid-50s, but showers are expected to move in by afternoon or the evening, the weather service said. Rain is likely overnight with more fog.
The reduced visibility can create hazards for on the road. Drivers should slow down, use low beam headlights and leave plenty of distance ahead in case a sudden stop is needed.
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