Some quick Sunday AM thoughts

Here are some very initial ideas for the winter weather potential starting late tonight through Monday/ Monday evening. My initial call maps are at the bottom of this discussion and remain subject to change through the day.

The parent high responsible for the maintanence of cold air damming will quickly slide out to sea Monday, so the type of cold air damming that will be in play will be what's called in-situ. That means the dome of cold air at the surface is maintained by evaporational cooling from precipitation.

A HUGE key to this forecast tomorrow is getting heavier rates of precipitation into the dome of initially very cold, extremely dry air. For the areas north of I-40, I like the odds of getting at least some decent snow for a period of time late tonight into tomorrow morning, which should help to lock the wedge in for a while.

Further to the south, toward Charlotte and the Upstate, I do not like the trends right now on a lot of the modeling regarding precipitation rates tomorrow. At this point, my thinking is that precip rates through the day tomorrow will be quite light for most of this area, and if that's the case, the wedge will not get as firmly established, and it won't be quite as cold as it potentially could be (for the more technically-inclined, I call this inefficient wet-bulbing...where dewpoints creep up at a higher rate than the temperature drops would otherwise be with higher precip rates).

So, this region could wind up with a lot of clouds, freezing drizzle, and some sleet pellets after possibly brief snow initially.

The band of heaviest precip will approach from the west tomorrow evening, and assuming what I mentioned above is correct, I would expect the Charlotte metro and Upstate to be above freezing, albeit barely. Areas further to the north, toward Hickory, Wilkesboro, and such, temps could still be sub-freezing. However, as we get toward tomorrow night, temperatures above the wedge of cold air at the surface warm substantially so that collection of freezing rain becomes less and less efficient, and it becomes a self-limiting process.

**What could go wrong??*** Well, if precip tomorrow morning winds up heavier than it appears right now, the dome of cold air will get locked into place further to the south, and areas down toward the Charlotte and Upstate could wind up with a longer period of icing. Also, initial snow totals, in this scenario, might have to be beefed up in northern NC.

Most locations in the region should climb above freezing tomorrow night as rain continues to move through. So, any road problems should actually improve as we get into Tuesday morning.

However, there is a good potential for travel issues as we get later into Monday in many areas as even a minor glazing of ice creates problems.

This goes without saying, but this is an extremely complex forecast scenario, and there are likely some surprises on tap in some areas. We will see.