This week's weather forecast looks very different than the last six weeks or so. Instead of above-normal temperatures, we're talking about a big impending cooldown. And instead of "wet not wintry," we have a couple of upcoming snow/ice threats to discuss too.

As promised, Sunday wasn't a half-bad day. Temperatures in the 50s with solid sunshine were countered by a fierce wind. (For those playing along at home, the top wind gust in NJ was 38 mph at Pennsauken, Camden County.)

Monday will be calmer, as winds have already lightened up. And it will be cooler, with highs only around 40 degrees. And while we'll see sunshine in the morning, skies will quickly become cloudier as the day presses on.

The daytime hours will be generally quiet and dry, but our next storm system is set to arrive Monday evening (possibly as early as about 5 p.m.) Precipitation will be on the light side — I'm calling it showers. However, temperatures will rapidly dip after sunset, which sets the stage for some wintry mix in northern New Jersey.

The geography for slippery conditions looks to be mainly north of Interstate 78 and west of the NJ Turnpike corridor — the usual suspects for wintry weather. In that area, up to an inch of snow accumulation and a glaze of ice is possible. (Freezing rain leading to ice would be the worst-case scenario — believe it or not, ice is very slippery!)

South of Interstate 78, there could be some snowflakes, but little to no accumulation and no travel issues are expected. Overnight low temperatures will range from the upper 20s to mid 30s.

A Winter Weather Advisory has been issued from 10 p.m. to 7 a.m. for the five counties in northwestern New Jersey: Hunterdson, Morris, Somerset, Sussex, and Warren.

Any showers (whether mix or rain) should wrap up by about mid-morning Tuesday. Then our weather will remain mostly cloudy but mild for most of Tuesday, as highs return to about the 50 degree mark. (Maybe even lower to mid 50s in South Jersey.) More showers will move in Tuesday night — thanks to the warmer temperatures, this round should be all rain.

The bottom will drop out Wednesday. High temperatures will reach about the mid 40s by late morning. And then, thanks to a brisk westerly wind (potentially gusting above 40 mph), thermometers will start to tumble.

Highs only in the mid 30s Thursday. Near 30 Friday and Saturday. Yup, that's cold!

And just as soon as temperatures plummet, we have a pretty significant coastal storm system worth watching in the Saturday night-Sunday time frame. Models have waffled back and forth between a "hit" and a "miss" for New Jersey. For now, I'll make the following four statements:
1.) If this storm system drifts close enough to the Atlantic seaboard, it would produce all snow across New Jersey.
2.) If this storm system tracks close enough to New Jersey, double-digit snowfall totals (10+ inches) would be possible.
3.) If this storm system passes anywhere near the Northeast, a notable arctic blast is likely for early next week.
4.) If this storm system does pose a serious threat to the Garden State, you'll be the first to know. (Beware the social media hype, which has already started to ramp up.)

Hopefully you get the sense that there are still a lot of if's out there. With about 130 hours until potential first flakes, it's a very volatile forecast. Models have literally flip-flopped between nothing and snow day. For now, we'll continue providing daily updates as usual. If this one is going to be a problem, we'll start ramping up the urgency and detail of this forecast around Thursday.

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