Sunday’s nor’easter: Wet start for some, snowy finish for all

The Latest Developments

There are two important updates to our winter storm forecast as of Sunday morning:

1.) Precipitation has been arriving in southern New Jersey slower than expected.

2.) Temperatures are even warmer than anticipated across the southern half of the state, with a rainier start for most.

After analyzing the current situation and latest model guidance, I believe these developments will affect the storm timeline, but not final snow totals.  My final snow accumulation map is exactly the same as the one I published Saturday afternoon, except for the addition of the teal contour to more specifically denote precipitation types.

Timeline

Precipitation will spread from south to north early Sunday morning, between about 5 a.m. and 9 a.m.  For the southern half of the state - approximately south of Mercer and Monmouth counties - you'll likely see rain or a slushy mix to start.  For northern New Jersey, I expect snow for the duration.

The brunt of the storm gets pushed back slightly.  Things will really go downhill starting around 9 or 10 a.m.  That's when localized heavy snow bands will reduce visibility and cause the quickest accumulations.  (Snowfall rates could reach an inch or two an hour.)  Even coastal areas could flip to moderate-heavy snow in the early afternoon hours.  The heaviest stuff should peter out around 2 p.m.

As the storm system pulls away, we'll see light to moderate snow end from west to east between about 2 p.m. and 5 p.m.

Totals

Same map as last time.  Although the mixing potential makes a good case for leaning more toward the bottom end of my forecast ranges than the top.

The sweet spot of the storm, approximately along the Turnpike corridor through inland southern and central NJ, should see about 4 to 6+ inches of snow.  The "plus" is important - while I don't think we'll have widespread 8 or 10 inch snowfall, such overperformance is possible depending on the banding structure.  (The NAM model was really bullish on that possibility even Sunday morning, so let's not discount the possibility of a major snow event just yet.)

To the north, you'll probably fall out of the bands of "pouring snow".  Still, 2 to 4 inches is enough to shovel.  And it'll be especially impactful with over a foot of snow still on the ground from last Monday's snow bomb.

Along the south coast, I'm keeping a 0 to 2 inch snow forecast.  I think this is where the greatest uncertainty lies in this forecast.  Models have been painting a pretty snowy scene along the Jersey Shore into Sunday afternoon.  So there is a chance for more than 2 inches here.  On the other hand, temperatures are pretty warm (43 degrees at Atlantic City and Cape May, as of this writing).  So I think it's reasonable to keep both none and some on the table.

Impacts

No matter what falls from the sky, it's going to turn rather unpleasant and sloppy through the middle of the day.  This will go a bit beyond "conversational snow".  Travel will become very difficult during the peak of the storm, from mid-morning through early afternoon.

Even for those headed out for The Big Game, roads may be in rough shape Sunday evening. Hopefully, crews will largely get a handle on snow removal by Monday morning's rush hour. I could see some schools and business delaying their open on Monday (or going virtual) as plowing operations continue.

Meanwhile, wind is not expected to be an issue during the storm.  You might encounter some gusts over 20 mph.  That will keep the risk of power outages and near-blizzard conditions low.

And because of the light-ish wind, storm surge and coastal flooding also won't be problems.  With only a few inches of water rise, not a single tide gauge along the Jersey Shore comes close to flood stage.

The Extended Forecast

Arctic air returns to the Garden State Sunday night, accompanied by a gusty northwest wind.  Overnight low temperatures will dip into the teens, with wind chills in the single digits.  Brrr!

A series of storm systems will bring us additional shots of wintry weather this week.  Although in full honesty, we do not have a great handle on precipitation types and potential accumulations yet.  The first impulse would be on Tuesday, and could be mainly rain.  Another complex storm in the Thursday-Friday time frame could be more impactful, with solid snow accumulation on the table.

We'll tackle those later.  One storm at a time, please.

Coverage Plan

I'm on your radio Sunday, across the Townsquare New Jersey Weather Network, until our nor'easter starts to wind down.  I'll have regular updates on the web, app, and social media throughout the day.

Our news team also is at-the-ready to communicate any problems with power outages, traffic and transit, closings and cancellations, etc.

Be smart, stay safe, and keep warm.  And enjoy the snow!

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