Dec 31: Cold New Years + Jan 4 Winter Storm Thoughts

Discussion: We’re very cold today through Tuesday as Arctic air reigns dominant. This poses a serious risk of hypothermic medical issues for those braving it outside for either the ball drop or any other outdoor activity surrounding New Years. If you are going to be outside tonight, expect temperatures to range from single-digits to teens with wind chill factors near or possibly even below-zero. Dress for an Arctic adventure! If you’re going to be one of those people on camera with your shirt off/skin exposed/etc., it will not “be ok because you’re drinking.” Temperatures then back off to just cold (no longer crazy cold) for the mid-week period surrounding the passing storm signal. Once the storm is out, regardless of hit or miss, the coldest air of the season then moves in for the Jan 6-8 period. After that we might see a transient January thaw before reloading the winter pattern shortly afterwards.

The January 4th storm signal has been advertised for a while now. Over the last week or so we’ve finally begun to see how the evolution of several shortwaves can phase together and produce a powerful low pressure wrap-up in the ocean. This idea is now becoming more confident. So I think we will at least see a powerful storm passing by out there in the Atlantic on Jan 4.

This is all going to come down to the timing of phased energy and therefore we have high volatility and variance in both low track and precipitation shield extent. There is very little high-latitude blocking and therefore the entire trough (once phased together) is going to want to move eastward. Our chance for a winter storm is based on the energy rounding the bottom of the trough quick enough to force a negative tilt to the trough axis…enough so that the ocean low gets pulled in a bit before lifting out and away with the rest of the trough.

If the timing were to cooperate then we could be looking at a major coastal snow storm where ENJ counties jackpot the accumulations and WNJ counties see less. It would be a quick taper-off as you head W just like the January 26, 2010 winter storm. If the shortwaves do not phase in time and the energy does not round the trough quick enough then we’re simply looking at an out-to-sea miss. A hybrid of these two possibilities would likely mean a coastal graze of light accumulations. Either way we should probably expect at least a minor risk of coastal flooding from the powerful storm that will be tracking S/SW to N/NE in the ocean.

Overnight model runs tonight and especially tomorrow during the day will give us a baseline for our initial forecast. Until then, we watch for trends in both computer data and live observations.

In English: It’s going to be bitter-cold tonight for the official New Year. I’m talking frostbite/hypothermia if under-dressed and outside for a prolonged period of time. Please use caution and dress accordingly if you’re going to brave it out like the people in Times Square! The January 4 winter storm signal that we’ve been tracking is more alive for the NJ coast than points west. Most model guidance now at least grazes the Jersey Shore with snowfall. It could be a major event with just a slightly west track/bigger precipitation shield or a miss out to sea if the dynamics do not happen in time. We’re continuing to track this potential and will have much more detail by tomorrow afternoon. I’ll also have the WeatherTrends360 January Outlook posted tomorrow. In the meantime, stay warm and please be safe! JC

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Jonathan Carr

Jonathan Carr (JC) is the founder and sole operator of Weather NJ, New Jersey’s largest independent weather reporting agency. Since 2010, Jonathan has provided weather safety and forecasting services for New Jersey and immediate surrounding areas through the web, social media, and app spaces. Originally branded as Severe NJ Weather (before 2014), Weather NJ is proud to bring you accurate and responsible discussions ahead of high-stakes weather scenarios that impact the garden state. All Weather. All New Jersey.™