Latest updates on N.J. snow forecast for Tuesday’s winter storm

The winter storm expected to dump up to a foot of snow in parts of northwestern New Jersey will likely start as rain for the vast majority of the state on Monday before transitioning to heavy snowfall for several counties as colder air pushes in overnight, causing slick conditions for the Tuesday morning commute, forecasters say.

The National Weather Service has issued winter storm watches for six New Jersey counties expected to see the highest accumulations ranging from 4 and 12 inches. Sussex County is expected to see the highest amounts between 7 inches and a foot of snow.

“Significant, at times heavy accumulating snowfall is forecast, mainly north of I-78,” the weather service said in an update on the storm Sunday morning. “Snowfall rates could exceed 1 inch per hour at times. This snowfall may have a significant impact on the Tuesday morning commute.”

The revised snowfall forecast issued early Sunday now calls for slightly lower amounts outside the winter storm watch areas of Hunterdon, Morris, Sussex, Warren and the western sections of Bergen and Passaic counties.

The I-95 corridor could see a slushy wintry mix as the rain shifts to snow toward the end of the storm, but it is not expected to amount to much, the weather service said.

“Cold enough air for some wet snow still looks to make a run at I-95, but with warm ground and pavement temperatures, any snow will struggle to accumulate,” the weather service said.

The heaviest snow in northwest New Jersey is expected after midnight on Tuesday.

The southern half of the state is expected to see heavy rain throughout the storm with widespread rainfall totals of 1 to 1.5 inches. Wind gusts around 30 mph statewide could top 45 mph closer to the Jersey Shore.

“Precipitation will taper off later Tuesday morning through afternoon from southwest to northeast,” the weather service said. Temperatures will drop into the 20s Tuesday night.

• Sussex County: 6 p.m. Monday to 6 p.m. Tuesday – Total snow accumulations of 7 to 12 inches possible. Travel could be very difficult. The hazardous conditions could impact the morning or evening commute.
• Western Bergen and western Passaic counties: 1 a.m. to 6 p.m. – Total snow accumulations of 5 to 9 inches with amounts upwards around 10 inches possible across the higher elevations.
• Warren and Morris counties: midnight to 6 p.m. Tuesday – Total snow accumulations of 4 to 8 inches possible. Amounts closer to the higher end of that range will focus across the higher terrain.
• Hunterdon County: midnight to 6 p.m. Tuesday – Total snow accumulations of 2 to 4 inches possible. Winds could gust as high as 35 mph. Confidence is lower that warning criteria snowfall could be met across this area and this could change to a winter weather advisory.

The weather service has also issued coastal flood alerts for high tide on Tuesday along the Jersey Shore and Delaware Bay. Moderate to minor coastal flooding is expected.

There could also be coastal flooding during the high tides on Monday, the weather service said.

Ahead of the storm, the forecast for Super Bowl Sunday includes more mild temperatures, though not as warm as Saturday. Highs in the upper 40s and low 50s are likely under cloudy skies.

Some light rain could fall in southern New Jersey early Sunday, the weather service said.

Current radar:

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