UPDATED Sunday, January 7, 2018 @ 5:17 AM CDT:
As precipitation moves into the area later tonight and early Monday, temperatures across the area will be around or slightly below freezing. About 3000 feet up an area of above freezing air will caused snowflakes to melt and become liquid rain. The below freezing temperatures at the surface will cause rainfall to freeze on exposed surfaces on contact.
Because of this, the National Weather Service has placed Marion County (and all other surrounding counties in TN, GA, and AL) under a Winter Weather Advisory.
A light glaze of ice will be possible, even on area roadways for the Monday morning commute.
Eventually, surface temperatures will begin to warm above freezing between 9am and noon. This should change the freezing rain over to all liquid for the entire region. Given the short duration of icy conditions, power outages and other ice storm impacts are not anticipated.
However, again, travel may be treacherous for your Monday morning commute. If you must commute remember to slow down and leave plenty of room between you and the car in front of you. Allow plenty of travel time to your desired destination.
Stay with MarionCountyMessenger.com for the latest.
Our team of meteorologists and forecasters at MarionCountyMessenger.com are keeping a keen eye on the weather situation as we get closer to Sunday night and Monday morning, and what could be our first winter precipitation event for 2018.
Ahead of the event we’ll see another cold night Saturday, dipping back into the upper teens to low 20s. Sunday will warm up a bit with some locations nearing 40°F by the afternoon with the help of some southerly winds. Skies will become mostly cloudy throughout the day Sunday.
As we head into the late night hours Sunday, the temps will fall again into the lower 30s to around or below freezing — and that’s when the action starts for our area as any rain could change over to a light freezing rain close to midnight, which would possibly continue into early Monday morning.
Some minor ice accumulation will be possible with this during the very early hours of Monday morning between 1 AM – 6 AM. We anticipate the areas west of Chattanooga will likely be most affected and specifically the higher elevations such as Monteagle, Tracy City, Palmer, South Pittsburg Mountain, Orme, Sewaneee and Cagle Mountain; however, we can’t rule out that areas in the valley around Marion and Sequatchie counties and parts of Northeast Alabama won’t see the effects of the precipitation, too.
For the snow lovers out there, this will come as a disappointment because we anticipate this to bring just freezing rain, which, in turn, means ice is our primary concern…which is nowhere as enjoyable as a receiving decent accumulation of even a dusting of snow.
Our primary concerns with freezing rain is the potential for a thin layer or glazing of ice that could form which could cause problems for Monday morning’s commute — with an icy glaze possible on some surface roads or secondary roads, bridges and overpasses, and and mountain roads.
The icy glaze can also cause problems when it lands on trees and powerlines, weighing-down limbs and branches that could break and fall into already over-burdened powerlines and potentially cause power outages or wreak havoc for some motorists getting into and out of some neighborhoods.
With all the potential for bad, now here comes the good…and also the maybes.
The good news is, any precipitation we see is expected to change over to rain before after sunrise Monday as highs warm to above freezing in the upper 30s near 40°F. We’ll see the chance for rain throughout the day Monday, nighttime lows dropping back into the mid 30s but staying above freezing.
For Tuesday, a a light drizzle early makes way to gradually-clearing skies throughout the day and warming into the low 50s. We could see highs near 60°F by Wednesday, with a better chance for rain later in the week and staying a bit warmer than we’ve seen of late.
As for the ‘maybes’ — With any winter forecast, ito’s fairly simple to look at the various weather models and ‘hit the nail on the head’ with moisture presence and precipitation along with the presence of cold air, among other things. Of course, a forecast is merely a prediction of what we ‘see’ happening with the weather by using fact-based and science-based studies, mathematics, measurements and technology to give you the best depiction of what to expect.
Unlike forecasting a severe weather outbreak or isolated thunderstorm threat with Doppler radar, which gives you an almost realtime depiction of what’s actually happening…with winter weather, many different atmospheric conditions and situations are in play which ultimately leads to what kind of precipitation you see, if any. That’s why often our best efforts at a snow or wintry precip event forecast can change and they often do change frequently leading up to an event.
To summarize, we do expect a winter precipitation event to impact the Sequatchie Valley, Marion County, and Cumberland Plateau late Sunday night into early Monday morning, with freezing rain causing icy conditions resulting in slick roadways and the potential for downed powerlines, tree limbs, branches and an overall messy and slick morning commute.
We will continue following the latest forecast models and monitoring things closely to bring you the latest information and any school or business closings or delays right here at MarionCountyMessenger.com!