An incoming cold front will change rain over to snow across all of Tennessee on Friday, potentially creating some travel concerns in the Cumberlands late Friday into early Saturday.
Snowfall totals continue to look less impressive, generally less than an inch, even as the timing of a transition from rain to snow continues to look earlier in the day Friday. In fact, the National Weather Service's Morristown weather forecast office is now forecasting a changeover to snow occurring between 4 p.m. and 7 p.m. in Scott County. As recently as yesterday, it appeared that changeover wouldn't occur until the early morning hours on Saturday. (The forecast still doesn't call for the total transition to snow to occur until around 8 p.m.)
In an effort to beat the weather, Scott High has bumped up the start time of its basketball game at Kingston to 5 p.m. Oneida has canceled its game at Coalfield; a makeup date has not yet been announced.
Overall, travel concerns should be relatively minor, but they will likely exist — particularly on untreated secondary streets and back roads.
It appears that the NWS in Morristown has opted against a winter weather advisory with this evening's forecast package. I won't pretend that I'm not surprised by this, and I won't pretend that I'm not puzzled by it. However minor this winter weather event appears to be shaping up, motorists need to know that they'll need to use caution after the sun sets tomorrow night and temperatures drop below freezing. (I would still expect a winter weather advisory to be hoisted by sunrise tomorrow.)
Here's what's happening with the latest forecasts: the storm system's increased speed is the result of less strengthening and deepening of the low pressure system, which is going to decrease the remaining moisture behind the frontal passage. Temperatures will crash quickly once the front passes tomorrow, but there won't be significant precipitation remaining.
While NWS-Morristown points out in its forecast discussion this afternoon that orographic lift will enhance the chances of continuing snow showers across parts of East Tennessee (which would include the Cumberland Plateau), it also points out that dry air will begin working its way into the atmosphere, which will limit snowfall potential.
The quick ending to the snowfall is illustrated by the renewed winter weather advisory that has been posted for Middle Tennessee (including the western edge of the Cumberland Plateau — Jamestown and Crossville) by the NWS office in Nashville. The winter weather advisory will take effect at 9 a.m. tomorrow morning and is now scheduled to end at 1 a.m. eastern time tomorrow night. It had originally been scheduled to remain in effect until about sunrise on Saturday morning.
In its forecast, NWS-Morristown is now calling for less than an inch of snow accumulation even here on the northern plateau, which lines up with what a lot of the most recent model data is showing. The latest run of the GFS forecast model shows 3-4 inches of snow for much of the northern plateau, but that model is an outlier without support from other models at the moment. The European model is showing a couple of inches for the region, but the NAM, high-res NAM and Canadian models are all showing less than an inch of snow.
Still, with temperatures quickly plunging below freezing, there should be at least patchy slick spots on secondary streets and backroads. The colder air may build in from the bottom up, which would mean a brief period of surface temps dropping below 32 degrees even as rain is still falling, which could result in a light glaze of ice, primarily on elevated surfaces. However, the rain will quickly change to sleet, and then to snow, as the colder air pushes in.
High school basketball games are already being impacted by this potential for wintry weather. Whether it proves to be sufficient enough to monkey with the schedule for Saturday's middle school basketball tournament finale at Scott High remains to be seen. It's likely that state routes will be in fine condition, perhaps throughout the event and certainly by Saturday morning, once the salt trucks have made their rounds to treat the road surfaces that have been washed free by the heavy rain earlier in the day. However, there is potential for slick spots to remain in shaded areas along secondary streets and back roads, as temperatures will remain well below freezing on Saturday.
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.