N.J. weather: Up to 10 inches of snow in possible ‘bomb cyclone’ winter storm. Updated forecast.

The latest forecast for a winter storm expected to hit New Jersey on Sunday calls for 4 to 8 inches of snow across the northern half of the state with up to 10 inches possible in some spots.

The highest snowfall totals of 6 to 10 inches are expected in the eight counties already under winter storm watches. Those watches will likely be upgraded to warnings as the storm approaches.

Snowfall rates of more than 1 inch per hour are possible during the peak of the storm on Sunday afternoon.

AccuWeather.com’s snow forecast map is calling for lower snow totals of 3 to 6 inches in northern New Jersey.

“This will likely end up being the first general snowstorm for the Interstate 95 corridor for the mid-Atlantic and New England, as storms this winter have not hit all of the areas with significant snow all at once,” AccuWeather Senior Meteorologist Tom Kines said.

“There is some data that suggests the storm could strengthen fast enough to be dubbed a bomb cyclone,” Kines said.

A bomb cyclone, or bombogenesis, is a popular term used by meteorologists to refer to when a storm rapidly intensifies, dropping at least 24 millibars over 24 hours. A millibar measures atmospheric pressure.

• ALSO: Early snow predictions from 9 forecasters for Sunday’s winter storm

While southern New Jersey and areas along the Jersey Shore are likely to escape this storm with low snow totals, there could still be a wintry mix changing from rain to snow as temperatures hover around freezing, the weather service said.

Through the central part of the state, particularly along the I-95 corridor, there is less confidence in the forecast. Snow total projections currently call for 2 to 6 inches.

“This is where the forecast will be the trickiest,” the weather service said in its Saturday morning update.

That area could see rain to start changing to snow, then flipping back to rain or sleet, before finishing as snow Sunday evening.

“There are still some notable differences in computer model guidance regarding the strength and track of the low and this will impact both the precipitation types and amounts,” the weather service said.

The storm is expected to start in southern New Jersey Sunday morning and spread north. The heaviest snowfall is expected in the afternoon and early evening.

“The good news is that this will be a fast moving system,” the weather service said. The storm should clear out by Sunday night.

Winter storm watches

Hunterdon, Morris, Sussex and Warren counties through 1 a.m. Monday – Heavy snow possible with accumulations between 6 and 10 inches from Sunday morning through late Sunday night. Roads, and especially bridges and overpasses, will likely become slick and hazardous. The strong winds and weight of snow on tree limbs may down power lines and could cause sporadic power outages.

Bergen, Passaic, western Essex and western Union counties through 4 a.m. Monday: Heavy snow possible with total snow accumulations between 4 and 8 inches possible from Sunday afternoon through late Sunday night.

Dangerous cold temperatures

The storm will usher in dangerous cold temperatures that will continue through the week. Wind chills below zero are expected in parts of the state through Wednesday.

The coldest day could be Tuesday with highs in the teens and overnight lows in the single digits.

Another shot of snow is possible on Tuesday night, though the forecast remains murky at this point, the weather service said.

“It does potentially get interesting again Tuesday night as a new low will be passing by to our south,“ the weather service said. ”This could brush the area with a period of some snow but it looks like the heaviest precipitation should stay to our south.”

Forecasters are also tracking another system that could move up the coast by Thursday night. By that part of the week, high temperatures should climb back into the 20s and 30s.

Current weather radar:

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