The Bottom Line
New Jersey is right on the edge of colder air to the north and warmer air to the south. Unfortunately, that "edge" is not a great place to be, as the boundary fuels persistently unsettled weather.
So over the next six days, we're expecting four distinct periods of rain. But also over the next six days, we'll enjoy mild (warmer than normal) temperatures.
The nicest day of the week will be Friday, which just happens to be New Year's Eve. The nastiest weather will be through the first weekend of 2022. And there's even a chance of accumulating snow on the horizon too.
We begin Tuesday the same way Monday ended. Damp roads and cloudy skies. Rain ended early Tuesday morning, but there's still some fog and patchy drizzle around. The only spot below freezing to start the day is far northern New Jersey, around Sussex, Morris, and Passaic counties — so that's the only place where light icing is a concern.
Most of Tuesday looks dry and relatively pleasant. Fog burns off by 9 a.m. High clouds will then allow some sun to poke through as the day goes on.
We'll probably see a wide temperature gradient across the state Tuesday afternoon. I've settled on a forecast calling for mid 40s to the north and mid 50s to the south.
Spotty rain showers may reemerge as early as this afternoon. And then most of the state will likely get wet Tuesday night (after 7 p.m.), as additional scattered rain drives through NJ.
Low temperatures Tuesday night will only bottom out around 40 for most of the state. The risk of wintry mix will be very limited to far North Jersey (north of I-80), if that.
The overnight rain showers should wrap up by Noon Wednesday. But it's not going to be a pretty day, as things stay dreary and cloudy and drizzly and misty and foggy through Wednesday afternoon.
Because of the sky cover and visibility concerns, I think temperatures will be held to the upper 40s. Note: That's still above seasonal normals for late December.
Another round of steady-ish rain is modeled to arrive early Thursday morning, between about Midnight and 10 a.m.). Rainfall will be light, less than a quarter-inch. And I see zero chance of wintry weather over NJ from that one.
By Thursday afternoon, I am hopeful we'll see some clearing. (Although the chance for a continuing isolated shower isn't zero.) If all goes well, highs on Thursday should push into the lower to mid 50s.
Friday (New Year's Eve)
I promised Friday will be the nicest day of the week, and I stand by that statement. I'll optimistically call for partly sunny skies and dry weather, with highs in the mid 50s. That is about 10+ degrees above normal for the last day of the year.
As the ball drops Friday night and we ring in the New Year, midnight temperature will be mild, in the upper 40s. You might want to wrap up your celebrations quickly though, as rain will move in by daybreak Saturday morning.
The Extended Forecast
A potent storm system complex will drive in two more rounds of rain through the New Year's weekend. The first will come Saturday morning through midday (that's New Year's Day). And the second possibly rolling through Sunday (that one's not a sure bet).
Some models (namely the GFS) are pumping out some heavy rain over the course of those two days. Total rainfall could exceed two inches.
The big challenge will come at the tail-end of the weekend, as a strong cold front ushers in much colder, drier air. If that arctic blast happens before the end of the precipitation, there could be a quick flip to snow by early Monday morning. Some models are even pumping out some shovelable accumulation.
However, there are some big question marks to be answered here. Will it snow hard enough and long enough for snow to stick to the wet, warm ground? Will dry air win out, causing a premature end to the precipitation? Will that Sunday rain even happen?
We'll figure out that snow potential as it gets closer. No matter what, you're in for a wintry shock heading back to work and school on Monday 1/3. Highs in the 30s, with a gusty wind? Ouch. At least it will be a sunny and dry January day.