‘Boom or bust’ nor’easter jogs north — big snow north, big rain south and coast
Almost all forecast models now show a slight northern shift in our nor'easter's storm track, putting the center of low pressure right over Cape May, N.J. (rather than over open water to the south and east). That is a notably warmer solution for us, forcing the rain-snow line farther north during the peak of the storm Wednesday evening.
The wiggle is not reason to panic, dramatically drop the snow forecast, and/or call it a bust. Yet. It just reinforces what I've been saying all along: This is a very complicated and track-sensitive forecast, subject to adjustments as the storm approaches and wiggles and wobbles. It's even more "boom or bust" now.
You'll noticed I decreased snow totals somewhat on my latest map — a move that I was fully expecting for the southern half of the state. I'm going to carefully watch the trend of the upcoming model cycles, before issuing a final call forecast early Wednesday morning.
It's going to be a very different storm on opposite ends of the state. Still, no matter how the numbers play out, it's still going to be a nasty storm with very messy weather and road conditions, strong winds, and coastal flooding. There will be travel headaches, especially during Wednesday evening's and Thursday morning's rush hours. There will be school and business closings. There will be power outages. There will be tidewater inundation.
I'm also concerned that weather conditions will spiral downhill faster than expected on the front-side of the storm. Wednesday evening's commute could get really sloppy, as the initial precipitation type for most will be straight snow. And I've shifted the timing of peak impacts slightly earlier, to about 7 p.m. to Midnight.
North Jersey (Orange)
Yes, we're still expecting cold temperatures, double-digit snow totals, and significant travel disruptions across the northern half to third of New Jersey. I did scale back snow totals slightly, now showing 10+ inches instead of 12+. I contemplated putting an upper bound of 14" or 16" or even 18" on that orange contour. But I'm much more comfortable keeping it semi-ambiguous for now, leaning toward the lower end of "double digits".
However, the northward shift makes it even more unlikely that 20+ inch snowfall will happen — you'll recall I never bought into that idea.
I do have some concern that the mixing line will drift as far north as the Interstate 78 corridor, obliterating those snow accumulations. That is the biggest factor I'll be watching as our final guidance comes in.
Initial snow in North Jersey will arrive between about 3 p.m. and 5 p.m. Wednesday. Slushy, icy roads and low visibility could become a big problem during the evening rush hour. The heaviest snow accumulation — the fastest pile-up — will come a little later, between about 7 p.m. and 1 a.m. An icy mix of snow, sleet, and freezing rain may creep in during this time frame. Things will start to really calm down just before sunrise (6 a.m.-ish) Thursday, with final flakes falling by around 10 a.m.
Expect wind gusts to about 35 mph during the height of the storm.
Central & Southwest Jersey (Purple)
Crafting a "perfect" forecast here is literally impossible — pinpointing such snow and ice totals goes beyond the current science of meteorology. Ladies and gentlemen, this is the "boom or bust" zone, where there will be a very tight gradient between appreciable snow on the ground and hardly anything. I've given you my best educated guess here, given our latest forecast information.
Initial precipitation through this battleground zone will probably fall as snow between 1 p.m. and 3 p.m. Snow will continue to fall through the evening commute, with some accumulation, reduced visibility, and sloppy road conditions. Then, after about 7 p.m., an influx of warmer air will enact a transition to rain and/or sleet. Light icing is a possibility. And some of that precious snow accumulation from earlier will be washed away. On the backside of the storm, a quick flip back to snow is a good bet, after about 3 a.m. Final snowflakes should fall mid-morning Thursday, by around 9 a.m.
Wind gusts to about 40 mph will be possible at the peak of the storm. Moderate coastal flooding is expected Thursday morning along the Raritan Bay, Atlantic Ocean, and back bays and tributaries. Minor coastal flooding may occur along the Delaware River and Delaware Bay.
South Jersey & The Shore (Green)
Well, I hope you like rain. Because with temperatures rising well into the 40s along the Jersey Shore, that's what you're going to get.
There will be a narrow window here at the beginning and end of the storm system for some wintry mix and snow. But snow accumulations will be very light, if anything at all. Between 1 and 2 inches of rainfall are expected.
First raindrops (and snowflakes) will bubble up from the southwest between 1 p.m. and 3 p.m. Wednesday. Roads look mainly wet for the evening commute, although there could be some slushy and slippery spots. Heavy rain develops Wednesday evening after about 6 p.m., leading to visibility, traction, and ponding issues. There could be some mixing with snow or sleet, especially the farther north and west you are. As temperatures crash early Thursday morning, around 3 a.m., a transition to all snow is possible. (Not a guarantee though.) Accumulations will be very difficult, with such a wet ground. Final drops and flakes are expected to exit the coast around 10 a.m. Thursday.
Wind gusts over 50 mph are possible as storm intensity peaks Wednesday evening, especially along the immediate coast. Those fierce winds will drive water toward the Jersey Shore, amounting to about 2 feet of storm surge. Widespread moderate flooding of tidal waterways is likely during Thursday morning's high tide cycles.
Less Than 24 Hours to Go...
Hopefully that gives you a sense for where we stand at the present moment. The next weather blog update will be published early Wednesday morning, by about 7 a.m. It will include our final call for snow totals, timeline, and impacts.