A Winter Weather Advisory is in effect for areas along and north of Interstate 80, where a brief period of minor icing is possible Monday night through Tuesday morning.

Monday Night SnowIce 20151228


Welcome to the last week of 2015! We are tracking a powerful storm system that has been digging across the middle of the country this weekend, dropping a swath of tornadoes and ice and snow and wind. That low will set its sights on the Northeast U.S. tonight through tomorrow. And so... finally... we are staring down the first chance of wintry weather of the season, but not for everyone in New Jersey.

As New Jersey gets clipped by this system, we are expecting precipitation to begin this evening (onset between about 6 p.m. and 11 p.m.) For the vast majority of New Jersey, temperatures will stay above-freezing tonight. So, for the vast majority of New Jersey, only rain will fall from the sky tonight through tomorrow. However, as temperatures fall to about 30 degrees tonight in far North Jersey, a brief period of wintry mix is expected and could cause some light accumulations of snow and ice.

Watches, Warnings, Advisories

Latest watches, warnings, and advisories
Latest watches, warnings, and advisories

The National Weather Service has issued a Winter Weather Advisory for:

  • Sussex County from 6 p.m. Monday to 11 a.m. Tuesday
  • Warren and Morris County from 7 p.m. Monday to 7 a.m. Tuesday
  • Passaic and Bergen County from 8 p.m. Monday to 6 a.m. Tuesday

An "advisory" is neither as serious nor as urgent as a "warning". Think of it as a "heads up" to potentially dangerous weather that may impact any travel or outdoor plans you may have.

Precipitation Type

GFS model forecast of precipitation type, showing a wintry mix in North Jersey through early Tuesday morning. (Image WeatherBell Analytics)
GFS model forecast of precipitation type, showing a wintry mix in North Jersey through early Tuesday morning. (Image WeatherBell Analytics)

The "cold zone" of subfreezing temperatures is generally expected to set up along and above Interstate 80 in New Jersey. I'm thinking the main precipitation type in this area will be sleet and freezing rain, with a little bit of snow too. That wintry mix presents the threat of icing concerns for part of the overnight - even a quarter-inch of ice accretion would make for incredibly slippery roads, and visibility could be reduced at times. Up to an inch of snow accumulation will be possible in the higher elevations of North Jersey as well.

Could we see a few snowflakes flying around south of I-80? Sure, maybe as far down as about the Raritan River. But I highly doubt anything will stick there, especially since the ground is still quite warm.

Eventually, an injection of warmer air in North Jersey will cause temperatures to rise above freezing. Any snow, sleet, or freezing rain will transition to all rain by late Tuesday morning. Meanwhile, any snow and ice on the ground will melt or wash away quickly.

While most of the Garden State will see only rain from this system, the Tuesday morning commute could still be a bit messy. Periods of steady or heavy rain will be possible from about 4 a.m. through Noon on Tuesday.

Extended Forecast

Tuesday looks wet overall, with rain potentially continuing through the early evening hours. Temperatures will vary greatly from north to south, thanks to the warm front that will sit on top of the state. Highs are expected to range from the lower 40s in far North Jersey, to the lower 50s in Central Jersey, to the lower 60s in far South Jersey.

Wednesday will be partly sunny and mostly dry, with temperatures recovering to the 50s - about 10 to 15 degrees above normal.

From Wednesday evening through Thursday morning, New Jersey will see one more round of rain. The GFS model keeps the rainfall light, but the NAM is currently showing some heavier rainfall through the overnight hours.

And then finally ... New Year's Eve will be the start of a prolonged period of dry weather, through at least early next week. Temperatures will be cool and near-normal, with highs in the lower 40s and lows just below freezing. There are no big storms on the horizon for New Jersey.

Dan Zarrow is the Chief Meteorologist for Townsquare Media New Jersey. Follow him on Facebook or Twitter for the latest forecast and realtime weather updates.