Saturday evening...

Some quick thoughts this evening....

How about the Saints/ Seahawks game?

Some discrepancies continues with the modeling regarding precip amounts. But, I am going to lay out a few very preliminary accumulation ideas. Please be aware that significant adjustments might need to be made as we approach the event.

For the I-85 corridor from the Upstate of SC all of the way up to the junction with I-77. Snow should begin by Monday morning, and the atmosphere should support all snow for this area until early afternoon at the earliest. After that, the temps aloft warm a bit, and there would be a switch over to sleet and mainly freezing rain. For the GSP area, I will go 3-5" of snow with a glazing of ice after that. For CLT, I will go 2-4," then the glazing. Western areas of the CLT metro could be more toward the 3-5" area.

The Columbia area is a very tough call. There will be a period of snow, but the warming aloft will be quicker down in that area, and a transition to sleet and freezing rain will then occur. The freezing rain potential is much more significant in this area, and at least a quarter inch of ice is quite possible....maybe more.

For the I-40 corridor from GSO to RDU....very very tricky. Precip amounts are a huge question mark. I will go with 2-4" of snow, and then a tenth to maybe a quarter inch of ice in some areas.

Back to the west, this looks like a good snow event for north Mississippi, especially along and north of Hwy 82, and in Alabama north of I-20. Tennessee also looks to see a good snow as well, especially along and south of I-40. I would think a general 3-6" type of snow in many of those areas, and that should carry over into northern Georgia as well. Many spots in the Tennessee Valley area could verify toward the higher end of (or even exceed) that range. I am still quite concerned about the ice potential in central MS, AL, and GA, but precip amounts are a question mark as some modeling is shifting the best precip up into the Tennessee Valley.

Some general ideas as I see it this evening. Be aware some fairly significant adjustments are always possible.

We will see how things look as Sunday unfolds. Keep an eye on the RUC modeling over the next 24 hours, and as we get deeper into Sunday, it becomes increasingly NOWCASTing time....meaning watching radar trends and surface obs instead of models.

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Saturday morning...

Some pretty big model fluctuations and differences continue in terms of amounts of precipitation with our approaching storm system. The 0z run of the GFS put out close to an inch of liquid equivalent precip near and just south and east of Charlotte while the 0z Euro and NAM were much, much less. The 6z GFS came in with about a quarter inch less than the 0z run. The 0z and 6z NAM held the 0.5" QPF line just south of Charlotte. (I just use Charlotte as a good singular point to reference the model differences.)

Winter storm watches are up for a lot of real estate. In the image below, all of the white counties from the Lower Mississippi Valley into the Carolinas are under winter storm watches.

My overall ideas have not changed. This should be a big winter storm for a good chunk of AR, MS, north AL, north Georgia, southern TN, and South Carolina. I feel like this will be a pretty significant event for at least southern NC, but the question marks get larger the farther north you go in NC due to uncertainty with precip amounts.

Below are the Day 2 and Day 3 winter weather maps issued this morning from the HPC.

Day 2

Day 3

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Friday afternoon.....

Some thoughts on the early week storm system. Below are two maps outlining my general thoughts on precip type areas. Keep in mind these boundaries are not hard and fast and might be adjusted. Also keep in mind I actually drew them up this morning. After reviewing the 12z data, I might tweak a spot or two, but the overall ideas remain the same.

This is seemingly always the range leading up to winter weather systems where lots of uncertainty seems to develop. I know seeing the QPF numbers continue to gradually wane, especially in NC, is extremely painful for snow fans to watch. I feel your pain. Generally speaking, there has been a trend in the modeling of weakening our southern branch feature every so slightly quicker than some of the previous runs.

Here is something of note....our disturbance is just as strong on the most recent run as it enters the Lower Mississippi Valley that it was on its run 24 hours ago. The quicker weakening takes place as it heads for the upper Southeast. I really think it is just a subtle difference in some energy over the New England states, but equally if not more important is the latest Euro is a little stronger with the next piece of energy in the Rockies.

Just comparing the Euro to the 12z run 24 hours ago, the difference in strength of the system as it enters the Southeast is small, but it is enough to cut the QPF numbers.

This is why I have been stressing, and continue to stress now, to not get wrapped up in QPF numbers. It is not good to get really excited or really down at this point about QPF, even still at this point.

Listen....the southern branch feature will definitely weaken as it approaches the Carolinas. It is a matter of how quickly it will weaken. That is the big question mark for Carolinas precip amounts.

Are the lower precip totals going to be a reality? Possibly, but possibly not. It is simply too soon to know.

This is really the point where I will just keep the forecast ship steady and true as we head into the weekend. I will not change the wording from my overall ideas that I have had out there. The potential for a widespread, significant winter storm from the Lower Mississippi Valley into the Carolinas is still very much there.

Will there be some disappointed people. Yes? Will there be some very happy snow fans? Yes.

Let's give it another 36 hours or so before anybody in the region (from Lower MS Valley to Carolinas) starts cliff-diving or starts the celebrations.

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