18Z GFS Model Track

I will stick with my graphic issued on the Winter Storm Page despite the GFS.

We're still 4-6 days out.

Significant Midwest Storm (January 17-19th) 00z GFS Analysis

This is the significant Midwest storm analysis potential for January 17th-19th. This is a 00z run, which is fairly old. I will be posting the new 18z run in a new post. So above, a deepening low will be in the Ohio Valley. As it deepens, the snow will become much more widespread and heavy over particularly the Southern Great Lakes.
Above, 6 hours later, the deepening low appears to be pulling moisture from the Gulf of Mexico, thus enhancing snowfall totals in the Southern Great Lakes.
Above, another 6 hours further, the storm begins to what may be collapsing, and the rain/snow line pushes up. However, most areas remain in an area of snow.
Above, still 6 hours further, the storm becomes defined in the Ohio Valley, bringing rain with it. Still, back in the Midwest, a band of heavy snow is thought to be occurring in North Illinois, with widespread light to moderate snow over the entire Midwest.
Finally, in the final 6 hours, the low moves off. The Midwest remains in the snow, and it slowly decreases in intensity throughout the next 18-24 hours.

Another analysis will be posted next.

Notice

Because I have seen so many people looking for a Snow Day Meter, I will make one.

Also, the Midwest Snowstorm page is closed and will now revert back to the Winter Storm Central.

The Snowday Meter will launch sometime late this month.

In-Depth Cold Outbreak Analysis

This is an in-depth analysis of an expected cold outbreak to the United States.

The first images shown are from the GFS model.

So in the first image above, we can see the jet stream setting up in the Siberian Express format. The jet stream takes a dive in the West Coast, straying south and keeping both them and the North cold.

The above image is of the projected jet stream position.

Step-By-Step GFS Midwest Storm Analysis

In this special analysis, we will use images provided by the EMC.

So, first out, on the below image, is about 12 hours out. We can see the precipitation moving into the Great Lakes and Midwest.

The low pressure will be in South Illinois at that time, weakening to possibly the weakest degree before it moves into the Ohio Valley. Precipitation should be most abundant in the West Midwest at that time.

6 Hours later, the snow finally shoots into the Great Lakes. The low will be in S. IL still, but more there and present. However, the heaviest precipitation will have already moved into the Ohio Valley.

Another 6 hours later, the low has progressed into the far south Ohio Valley, also bringing along the heaviest snows with it. Lingering snow will continue in the West Great Lakes.

Finally, the two lows combine on the East Coast while lingering snow ends in the West Great Lakes but continues in the Ohio Valley.