Major Winter Storm To Affect Much Of The U.S. Next Week

Hi everyone. In the last day or so, all major forecast models have come to a consensus that a major winter storm will affect a wide swath of the country during next week. However, there are major differences among the models with regards to where the storm will track. With that in mind, today I am going to take a look at how the storm will form and why it's going to be such a major storm. In addition, I will mention my personal opinion on what I think is going to happen with this storm, and potential impacts for Lake Orion.

Disclaimer: The first three sections deal with in-depth weather terminology, though I have attempted to make everything as simple as possible through helpful graphics. The final two sections are much more similar to my normal blogging style.

How The Storm Will Form:

Essentially, two pieces of energy in the upper level of the atmosphere are going to combine over the Western U.S., which is the basis for the storm. This is shown in the image below from the NAM model. I have circled the two individual pieces of energy for the sake of simplicity.

However, this is not a perfect phase between the two pieces of energy. As represented by the blue circle on the GFS model in the image below, a lot of upper-level energy is left behind in the Southwest U.S. The fact that so much energy is left behind means that the storm is not as strong as it could possibly be if a more aggressive phase took place. The energy that does phase is shown by the red circle in the image below (this is the energy that was represented by the blue circles in image one.

Why It Will Be Such A Major Storm:

Despite the storm likely not being as strong as it could possibly be, this is still likely to be a major winter storm. I will use the image below from the NAM model to try and explain why. First, look at the blue polygon I placed over the Texas Panhandle, Oklahoma, and Kansas. This polygon is meant to draw attention to the strongy baroclinic zone over the region in the polygon, which is represented on the map by the tightly packed blue and red lines. Basically, the baroclinic zone represents the temperature gradient...and a strong baroclinic zone favors a strengthening system. In this case, the baroclinic zone is obviously very strong which favors a strengthening system.

Second, look at the curved green lines I have drawn which extend from the Gulf of Mexico up into the Ohio Valley. These lines were made to draw your attention to the excellent moisture feed extending from the Gulf of Mexico up into the Northern U.S. ahead of the storm. Southerly low level winds will bring up warm, moist air from the Gulf of Mexico into the Northern U.S. The low level wind direction is shown on this map, and in case you do not know what it looks like...I circled one of the symbols in black in Southwest Louisiana. The wind blows from the direction of the part of the line without any bars on it...for example, in Southwest Louisiana, the wind is blowing from the SSW. The take home message is that the storm will be able to tap into the moist air and produce a lot of precipitation as a result.

Factors Affecting The Storm Track:

There are different factors that I believe will (a) prevent the storm from cutting too far west for SE Michigan to get a significant snowstorm and (b) also prevent the storm from tracking way to the south like previous storms. However, a miss to the south and east is still more likely for SE Michigan than a miss to the north and west. I'll explain more in a bit, but first, let's look at some images to show what I'm talking about.

The image below from the GFS model shows a 1048mb high pressure system located just north of Montana as the storm is getting its act together. As a rule, storms track around high pressure systems, and since this is a very strong high pressure system, it will likely prevent the storm from tracking too far west and giving SE Michigan a rain storm. A storm track through Chicago, for example, is unlikely in my opinion because of this strong high pressure system.

On the other hand, the image below, also from the GFS model, shows why I don't believe the storm will track way to the south like previous systems over the last month. The reason I believe this storm will track further north is because the height field is more amplified than with previous storms. This is showcased by the black line located in between the red lines that I drew for visual effect. The fact that the black line is amplified means the storm will be able to move to the north, although, as I mentioned earlier, some of the northward movement will be limited by the strong Canadian high pressure system. The simplest way to put it is that it's a balancing act between opposing forces, which is part of the reason why the storm track is so sensitive.

My Personal Track Preference For This Storm:

First, it is necessary to discuss the storm tracks of the latest GFS & ECMWF runs, as my storm track will be in comparison to those. The GFS tracks the storm from Memphis, TN to Lexington, KY to Pittsburgh, PA before transferring energy to the coast. The GFS shows little to no snow for most of SE Michigan. The ECMWF, on the other hand, tracks the storm from Little Rock, AR to Indianapolis, IN to Cleveland, OH. This is historically a great winter storm track for SE Michigan and this time would be no different, as the ECMWF shows all of SE Michigan getting over 1' of snow.

My personal preference at this time, due to the factors I mentioned above, is for a storm track that is in between the extremes shown on the ECMWF and GFS. The likely result of this track for SE Michigan would be a decent winter storm, although not to the extent of that shown on the ECMWF. Someone will almost certainly get over 1' of snow from this storm, but with my predicted storm track, that someone would likely be to the south of SE Michigan.

In Conclusion:

A major winter storm will affect a large portion of the U.S. in the middle of next week. Depending on the track, SE Michigan could get any variety of weather, ranging from cloudy skies with no snow, to a major snowstorm, to a crippling ice storm, to a dreary rainstorm.

At this time, I believe it is more likely the SE Michigan will be to the north of any snow (cloudy skies) as opposed to getting a dreary rainstorm. I also believe a snowstorm is more likely than an ice storm. All four possibilities are in play however. If I had to rank them, I would probably rank them in the following order: (1) Snowstorm, (2) Cloudy Skies, (3) Ice Storm, (4) Rain Storm. The most probable snow days that could occur from this storm are on Wednesday, February 2nd, and Thursday, February 3rd.

In conclusion, I believe at this time that a decent winter storm is becoming more likely for SE Michigan. If everything goes right, it could be a very major winter storm for SE Michigan. Despite the remaining uncertainty, this is easily the best chance for a major winter storm for SE Michigan since December 12th, 2010.

Stay tuned to the blog as I will likely have more posts and/or videos up throughout the weekend. As always, thanks a lot for taking the time to read, and please feel free to leave questions/comments in the comments section below.