Good Afternoon Folks! We are enjoying this warmer weather today and so should you as Old Man Winter returns later tonight, with temps below average beginning tomorrow, hanging around through the end of the weekend. Although everyone and their brother is talking about the potential for snow this weekend, let's take a glance at the week ahead before boarding the hype train. A front swings through tonight, ushering in colder air and light, spotty snow showers for the TN line after midnight. A second disturbance swings nearby Tuesday afternoon, prompting another round of light snow for the TN line area that will hang around till Wednesday morning, with light accumulations at best. Thursday and Friday remain chilly with a gradual increase in cloud cover, becoming mostly cloudy by the mid - late afternoon hours. Temps all the while will be below average, dipping to their coldest levels of the week early Thursday morning. The models point to a high pressure system funneling cold air into the region Friday, with moisture riding overhead Saturday into Sunday and if some of the models are to be believed, snow will fall for most of the region. But don't freak out just yet. Due to the topography of our region, Cold Air Damming events rarely work out for us and some of the models show the high pressure weakening or exiting before the precip begins, so a lot of uncertainty this far out in time. If you do have weekend travel plans, this is one forecast to follow daily as things will change day to day leading up to the event.
The rest of today will feature mostly sunny skies with high and thin clouds filtering in as the day moves along, becoming partly cloudy tonight for most of the region. The TN line area will experience mostly cloudy skies as the front moves through and as temps dip below freezing, isolated rain showers will kick over to snow. We don't expect much in the way of accumulating snow, but a dusting is possible for places like the Smokies and Cataloochee Ski Area. Temps today hit the upper 40's - upper 50's and drop like a rock to the mid 20's- low 30's tonight (depending upon elevation) as NW flow takes control.
Tuesday through Friday keep temps to the mid 30's along the ridgelines, while the valleys only reach the mid - upper 40's, however Wednesday is likely to hold temps to the upper 20's - upper 30's as the coldest air of the week passes through the area. Sunshine and a few clouds make up most of the action for the majority of the region Tuesday and Wednesday, while the usual suspects along the TN line deal with intermittent light snow showers that could produce another dusting by early afternoon Wednesday. Everything clears out before sunset Wednesday and as winds die down, clear skies setup shop and allow temps to plunge into the mid teens - low 20's. Thursday offers up sunny skies and clouds fill in as the day moves along Friday.
The tough part of the forecast begins Saturday as the models remain split in how to handle the passing low pressure system to our south and high pressure to the northeast. If the low passes along the Gulf Coast and rides up the eastern seaboard, the chances for snow increase for most of NC, however if the low passes more northerly, say through middle Georgia, then a cold rain is more likely. The other factor to consider is the strength and placement of the high pressure system across the northeast, as this is the mechanism that funnels cold and dry air into the region. This is what we call Cold Air Damming as the cold and dry air literally dams up against the Appalachians. In most cases the Great Balsams (Jackson/Haywood county line) and escarpment (mountains dropping off to the foothills along the SC state line) block this intrusion of cold air, however the high pressure system can be strong enough to overcome these physical barriers. What we need for a region wide snow event is for both to come together, a strong CAD in place with a low pressure to our south and east, allowing the moisture to ride over top the in place cold and dry air. Because the models are just now sampling the system in Arizona as it comes off the ocean, we still don't know for sure which scenario will play out, but we should have a better handle by Wednesday morning. The best chance for snow at this point in time (in our area) will be along the Great Balsams and perhaps elevations above 4500' along the escarpment. We will produce a SNOWCAST Map for this event late Wednesday afternoon (if warranted), so stay tuned and be sure to stay away from social media hype posts but to instead follow other weather outlets like the NWS or WLOS.
We'll be back Wednesday afternoon!!!