Weekend Blitz

The winter storm that will impact the state this weekend is getting its act together this morning as snow is already flying in portions of Wyoming and Colorado. It will make its way up this direction starting tonight and going through Sunday morning. Exact timing and snowfall amounts are still a little shaky right now but it is becoming more clear. That being said, it is becoming more clear that some areas could pick up some pretty large amounts of snow. Here is the reason I say that. When looking at the forecast models, you try to look for the subtle things that may enhance or decrease precipitation to try and get a more accurate forecast. Well, when I was analyzing this morning I came across something that got my attention. I looked at the 700mb level (about 10,000 feet) and found a convergence boundary. If you look at the wind barbs on the first picture (just disregard all the colors), you will notice that the air is circulating around the low pressure in a pretty evenly spaced pattern. Well, when you look at the second and third pictures, you will notice that the pattern is no longer evenly spaced and you have winds that seem to run into each other (I have circled them). When this happens, it provides extra convergence in the atmosphere, which enhances lift in that area, which can enhance precipitation. In this case, likely in the form of snow. This convergence band sets up over the Sioux Falls area and moves eastward over time. So, this could actually provide those areas affected with lots more snow then in many other locations. A form of this happened during the last storm system when places like Mitchell and Chamberlain got a foot of snow. Now I'm not saying that we will get a foot of snow, however, if this particular model is correct, then it is a possibility. So I guess we will just have to wait and see.

Still some discrepancy in models about the amount of snow that will fall. However, they are all generally in consensus that the heaviest snow will fall in southern SD and northern NE. The question is now, how much snow is the heaviest. Here are a few of the model forecasts.

~KDLT Meteorologist Cody Matz