Bitter cold temperatures, potential blizzard, are just over a week away

A looming arctic blast of cold air will send Scott County and much of the region into a deep freeze for a few days in early January if current expectations hold. And although it is too early to say for sure, there may also be some snow along the way.

A combination of a positive North American Ridge Index (PNA), a negative Arctic Oscillation (AO) and a negative North Atlantic Oscillation (NAO) is establishing itself in the first half of January. While there are more determinants of winter weather in the southeastern US than just these three teleconnections, the combination of a +PNA/-AO/-NAO is typically a good look for cold and potentially snowy weather in Tennessee and neighboring states. In a nutshell: PNA measures smoking in the eastern Pacific and along the West Coast, and an atmospheric ridge out west typically means warmer weather there, along with atmospheric lows and colder weather in the eastern United States. The AO measures storminess in the Arctic region, with a -AO favoring cold air being forced into the continental US, and the NAO measures storminess in the North Atlantic, with a -NAO indicating the potential for some sort of jet stream roadblock, that forces colder air farther south in the eastern United States and gives it more persistence.

It is therefore not surprising that there appears to be a high potential for a period of very cold temperatures across much of Tennessee during the second week of January. We’ve talked about this possibility briefly for a few days now in our daily “Eye to the Sky” forecast updates.

The colder weather begins after the passage of a New Year’s Eve cold front. In Scott County, we’ll go from temperatures in the mid-50s on Tuesday to temperatures struggling to get out of the 30s on Thursday and Friday.

The second wave of cold air arrives this weekend and we may struggle to get above freezing on Saturday, although we may return to near 40° on Sunday.

How cold we get depends on the development of the pattern after that. But global models are pretty consistent with a strong wave of cold air engulfing much of the Midwest and spreading to parts of the Southeast around Tuesday of next week. That could mean temperatures that don’t get into the 20s until Tuesday and may struggle to get out of the teens on Wednesday. We could get a bit warmer Thursday and Friday next week, but probably won’t get above freezing if current projections hold. Then there is the potential for an even bigger blast of cold air in the second weekend of January, with the possibility of bitterly cold temperatures around the 11th-12th. January.

Again, all of this is just potential right now; the pattern continues to evolve, and some details may change—perhaps even significantly—between now and then. But today’s midday run of the GFS model, a global model run by the National Weather Service, is the best look for sustained cold air you’ll ever find in Tennessee during the month of January. If that was taken literally, we would drop below freezing next Monday night and not get above freezing through the end of the run, which takes us to the morning of Tuesday, January 14th. And we would get as cold as the lower single digits on the mornings of January 11th and 12th.

ECMWF, which is a European counterpart to the GFS model, shows a similar appearance, although not quite as cold. Other global models run by the National Weather Service’s counterpart in Canada and the UK show similar scenarios. This broad agreement among the global models lends a lot of credence to the idea that the second week of January will be quite cold in Tennessee and Kentucky.

James Spann, a well-known television meteorologist in Birmingham, Ala., pointed out Sunday that the looming Arctic blast will be similar to the December 2022 Christmas freeze, which was one of the coldest Christmases on record in Scott County. But he adds that some analogues indicate that the coming period may be even colder than that.

As for snow possibilities, we have been suggesting for several days that there are strong winter storm signals in the second week of January. It is still impossible to predict where it will snow, or when and how much snow will fall. But those options are still on the table.

A verbatim take-away of this midday round Sunday of the GFS model mentioned earlier, which was so cold for the northern Cumberland Plateau region, takes the idea of ​​snow off the table for all of East Tennessee, outside of the usually favored areas in the mountains. The same model, on its next run six hours later, showed light snow for the northern plateau region, although it continued to push the heavier snow farther north, across the Midwest.

The ECMWF model, meanwhile, shows a winter storm forming and taking a solid hit for all areas along the Tennessee-Kentucky border, including Scott County.

If a winter storm does form, it will likely be sometime in the Saturday to Tuesday time frame of next weekend and into the following week as the coldest air begins to rise south.

Currently, the National Weather Service has a 30% chance of snow in the forecast for the Oneida area on Sunday.

Details of a potential blizzard will continue to emerge, and likely change a lot, over the next three or four days. If you’re one of those winter weather geeks rooting for snow, you know that getting a solid blizzard in the Southeast, even as far north as the TN-KY border, is almost like threading a needle. A lot of things have to happen just right for snow to accumulate here, and even when snow seems likely, it’s very common for a fly to land in the ointment and ruin it all. For now, the trends are favorable for at least a small snow accumulation sometime around seven to 10 days from now. However, the much safer bet is a week of very cold temperatures that looks set to be headed our way.

Now is the time to take care of any winter prep tasks you’ve been neglecting around the house, such as insulating exposed pipes, checking the antifreeze in your vehicles, and properly preparing dog kennels and chicken coops. There’s a good chance the coldest weather we’ll see all season will begin in just over a week from now.

A reminder: you can always find the latest weather forecasts and conditions on our Eye to the Sky page. With the potential for a disruptive blizzard on the horizon, however slim those chances are at the moment, we will also be posting frequent updates on our social media platforms as the outlook becomes clearer over the next few days.