All weather enthusiast have been keeping their eye on the extended forecast as there could be a big storm system on the horizon (December 21st-22nd). Now we want the emphasize that this is still a week a way so a lot will change and nothing is set in stone. We simply want to show you what we are looking at so you can see what is on the horizon as this storm is so close to Christmas and a lot of people will be travel during the heart of this potential storm system. We continue to look over the data as it comes in, which in many cases is four times a day. If this storm system happens and comes together just right, we could be looking at a powerful storm system that could affect a large area of the central Midwest.
Now the tricky part for forecaster is what model to make your judgments off of. The Euro, which is usually the most accurate is the most aggressive at this point and because of that, I am apprehensive to rely on it. Current track of the Euro, has a low moving through southern Missouri, southern Illinois, and off through the Ohio river valley. Snowfall totals with the latest Euro run are off the charts. If the Euro is the one that does verify, this could be crippling to holiday traffic in the central Midwest. As a forecaster, it’s hard not to go crazy seeing snowfall totals over northern Indiana of 24”. However, this looks to be the extreme case right now as the GFS and the GEM (Canadian model) are not this aggressive and have a slightly different track. Because of this, I am not buying into this model.
The GFS model earlier this morning had the snow in southern Missouri, southern Illinois and through Indiana and Ohio. It has since shifted to the northwest and is taking more of a track like the Euro. However, the BIG difference is the GFS is not off the charts with snowfall totals. The GFS is more reasonable with snowfall totals ranging from 3 to 6 inches in the Midwest.
The GEM differs from the two, as the track is even more to the north. If the GEM was the one to verify, this would have the snow falling across central and eastern Kansas, most of Iowa, northern Illinois, Wisconsin, and off into Michigan. Snowfall totals range from 3 to 8 inches of snow with this model.
The BIG question will be if the polar jet stream and pacific jet stream come together in the southwest. If it does, then it is very reasonable to have a large snowstorm in the central Midwest. If it doesn’t then snowfall totals would be comparable to the GFS and GEM. Right now, it looks like most of the state will miss out on this snowfall with the exception of southeastern Iowa. However, as stated earlier, this system is still six days off so a lot will change between now and then. We will continue to track the very latest right here at Iowachase.com and will bring you the very latest updates on our Facebook page as we get closer to this event.