A rainy and cold Sunday night could lead to icy conditions overnight before heavy snow picks up across much of North Jersey Monday, the National Weather Service said in an update.
Snow falling across the state is expected to turn to rain around 4 p.m., making for slick roads overnight, the NWS said.
Ice accumulations may be higher than previously forecast, with up to half an inch possible due to sleet and freezing rain in Sussex County.
Snow was expected to fall all day Monday in the north-western part of the state, with up to nine inches possible in Sussex, Morris and Warren counties, the NWS said.
Between four and six inches of snow were forecast in Bergen, Essex, Union, Hudson and Passaic counties, according to the NWS.
Monday's afternoon and evening commute could be messy and dangerous.
The NWS issued a Winter Storm Watch and Hazardous Weather Advisory in the northern part of the state from Sunday to 7 a.m. Tuesday.
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