We're in the midst of yet another wave of arctic air, the latest in what seems to be a relentless stream of air straight from the polar region that has kept the Mid-South in the deep freeze for the past week.
Thursday's official high temperature, as recorded by the National Weather Service, was 34 degrees. That's very misleading, though; it was recorded at midnight, before the frontal boundary reached the northern Cumberland Plateau and the colder air started to filter in. Once that happened, we plunged all the way to two degrees by daybreak, and failed to get out of the low 20s during the daylight hours. The temperature was down to 11 as of 9:30 p.m., on its way to an anticipated overnight low near zero. And temps will fail to rise much above 20 again on Friday. Then temps may be colder on Friday night than they will be tonight, at least by a couple of degrees, and we'll remain in a hard freeze on Saturday, with the NWS forecasting a high of just 24 for Oneida.
There is an end in sight, though.
The brutal cold will come to an end this weekend, and then the below-normal temps may end within the next 10 days.
Sunday will finally see temperatures rise above freezing, as a southerly flow kicks in ahead of a storm system that will impact the region Sunday night into Tuesday. Model guidance from the GFS forecast model suggests a high hitting 40 degrees; the NWS is going a bit colder in its forecast, keeping temps in the upper 30s. Either way, Sunday should be the warmest day in over a week, and Monday should be slightly warmer than Sunday as the warm air advection continues.
The end of the extreme cold this weekend — the temp is expected to drop to about 12 degrees overnight Saturday into Sunday before the milder air begins moving in — will mark the end of this brutal stretch of weather for the foreseeable future. It had at one point looked as though another wave of arctic air would filter in behind the upcoming storm system, but now it looks as though the frontal boundary won't make it quite this far south. Instead, we'll gradually warm next week, and could hit 50 degrees by Thursday, if not Wednesday.
It's worth noting that the NWS is forecasting rain mixing with or changing to snow on Sunday night, and again on Monday night before tapering off. The weather agency is forecasting a low of 30 each night. With the ground being as cold as it is, that could lead to some interesting travel scenarios both Monday and Tuesday mornings, if it were to pan out. However, some model guidance is quite a bit warmer than that. The GFS, for example, keeps us in the mid 30s both Sunday night and Monday night. Given the warm air advection that will be occurring with this system, I wouldn't be a bit surprised if this doesn't prove to be the correct solution, and we might see the NWS increase its forecasted overnight temperatures for those nights.
A better chance for snow could come at the end of next week. That's when the next intrusion of arctic air looks to be headed our way. Currently, it doesn't look as though it'll get nearly as cold as it's been this week, but there's a storm system that'll usher in that colder weather, and that could be interesting. We'll initially be all rain, with plenty of warm air advection under a southerly flow ahead of the system, and with the low pressure system itself passing over or very close to the Tennessee Valley. But as the low pulls away and the colder air filters in, all models hint at a changeover to at least a brief period of precipitation. For now, the European model is the closest to being a significant winter weather scenario for the plateau region, but the latest run of the GFS isn't far away from an accumulating snow for our area. The Canadian model also shows snow on the back side of the system.
Whether or not we see our first accumulating snow of the season at the end of next week (Jan. 12-13), it looks to be winter's last hurrah for a while, as warmer air builds in the following week. We could see a return of widespread 50s and even 60s as we move later in the month.
That will be the start of a pattern reload that will take us through late January. For now, long-range modeling indicates a return to colder weather around the end of January or early February, but that's a long ways off and subject to change.
Eye to the Sky is a weather blog by Independent Herald editor Ben Garrett. Garrett is a weather enthusiast who has long blogged about interesting weather on his personal website. He is not a professional forecaster or a meteorologist and information on this blog should not be considered a substitute for forecasts, advisories or other products from the National Weather Service.