December 21st-24th, 2022 | Plains/MW/GL/OV Winter Storm

[Sentinel]

32 minutes ago, cperry29 said:

GFS is at least workable. CMC on the other hand, sticking to the cutter idea.

CMC and GFS are on 2 different planets. 

It all comes down to the AK shortwave. 

[Ohiobuckeye45]

Just now, Ohiobuckeye45 said:

the cold air is slow as molasses on the UK compared to other models 

same time stamps

 

[SOMOSnow]

2 minutes ago, Ohiobuckeye45 said:

this is 3 systems combined (2 for plains) 2 for NE

Wb has some different totals with kuchera. Always interesting to see differences. 

[Ingyball]

Shift the Ukie about 100-150 miles south and I think that's a realistic track.

 

 Anyways I just went and took a look at ICON soundings over Kansas and oh boy, we're talking about a saturated DGZ that's 12-13k feet deep. That's 25 to 30-1 ratio type stuff. Would be a heck of a storm.

 

 

 

 

 

 

 

 

 

 

Edited December 17, 2022 by Ingyball

[SOMOSnow]

0z UK to hour 144. These are 10:1. Looks pretty potent so far. 👇❄️

Edited December 17, 2022 by SOMOSnow

[Ohiobuckeye45]

6 minutes ago, SOMOSnow said:

Wb has some different totals with kuchera. Always interesting to see differences. 

yours is also capturing a third wave on the 26th in some places

[SOMOSnow]

To offer more perspective on 0z UK, here is the final 6 hours of snowfall at 10:1. It's getting it as the ratios there will be much higher than that. 

[SOMOSnow]

Just now, Ohiobuckeye45 said:

yours is also capturing a third wave on the 26th in some places

Oh ok yea I tried to run thru Christmas day. Good catch. 

[Iceresistance]

14 minutes ago, Pghsnow said:

Perfect for me! 

[Ohiobuckeye45]

[Ohiobuckeye45]

mean

[Ohiobuckeye45]

I'm surpised those of you west havent resurfaced the 19th-20th thread

Edited December 17, 2022 by Ohiobuckeye45

[SOMOSnow]

1 minute ago, Ohiobuckeye45 said:

I'm surpised those of you west havent resurfaced the 19th-20th thread

I will 

[Ingyball]

4 minutes ago, Ohiobuckeye45 said:

Member 7 please!

[SOMOSnow]

0z GEFS mean to hour 177. Again, just 10:1 ratios. Mean actually gives me a little more snow than 18z gefs did even with a much bigger hit from 18z gfs op. I like to lean on ensemble means this far out as I feel that's a more consistently reliable indicator or where things likely stand. Sorry that this cuts off far NE. 

[Iceresistance]

2 minutes ago, SOMOSnow said:

I will 

All because you are probably the only member here other than @Ingyball for flurries being impacted with snow on that event, lucky you!

[Iceresistance]

4 minutes ago, Ingyball said:

Member 7 please!

I'll second that order!

[SOMOSnow]

7 minutes ago, Iceresistance said:

I'll second that order!

Same. Or 20. 

[Ohiobuckeye45]

the KMA is coming in as a hybrid bowling ball/apps runner, there will be huge totals in the OV once its completed running 

 

 

 

[SOMOSnow]

0z GEFS mean through hour 192 at 10:1 ratios. 30 members here fwiw. I forget why. I read up in it before if I recall correctly..

Edited December 17, 2022 by SOMOSnow

[Ohiobuckeye45]

[SOMOSnow]

0z Canadian ensemlle mean 10:1 through 192 is improved slightly for most spots vs 12z. 

[Snow____]

7 hours ago, MesoscaleBanding said:

Where's @FortySixAnd32, @Snow____ & @snowlover2?

https://media4.giphy.com/media/tmPgV8TrMjh0XeWrRq/200.gif

Is it that time of year again? 

Edited December 17, 2022 by Snow____

[Sentinel]

My 2 Cents:

From what I can see, it appears that the TPV (see below) is being affected by a shortwave in Alaska which is impacting the tropospheric circumpolar vortex (TCV - Please see picture below for additional assistance as I explain), which in turn is altering how the TPV itself is manifesting, thus changing the baroclinic zones and allowing for bombogenesis near the Midwest rather than the EC. So.. let me break that down. 

The TPV is known as the Tropopause Polar Vortex. We will get to this in a minute, however, let's start with the TCV.  The TCV is a large rotating column of air which is loosely wound around the Poles. In our case, we are affected by the one rotating around the North Pole. This loosely rotating column of air is centered on the North Pole and can reach as far South as the Southern United States, though this Southern boundary tends to fluctuate between Canada and the Southern US (this is a bird's eye view explanation. There are some very technical and intricate features which I am glancing over). 

That being said, let's get into the TPV. The TPV is what most people think of when the Polar Vortex is mentioned (ie media, public, etc). What a TPV actually is, is a lobe within the TCV. Basically, It is a HP System which forms within the rotating column of air that is the TCV. When this lobe develops, it is normally what is responsible for an Artic Air Intrusion into the United States. The thing about TPVs is that they are rather susceptible to other energies within the TCV. 

In this particular case, the TPV is being affected by a vigorous piece of energy over Alaska. This piece of energy (a shortwave) is still poorly sampled and -as mentioned previously- is in no man's land Alaska. The difference in the current models appear to be attributed to this shortwave feature. What appears to be happening is that the models which are keeping the shortwave less vigorous are thereby keeping the TCV with less perturbation (or ridges and troughs - ie more zonal). This zonal flow allows the TPV to settle further into the center of the country. In other words - the more zonal flow changes the momentum and thus where the artic air intrusion first begins. In turn, this changes the baroclinic zone and therefore where the Low-Pressure System eventually sets up. (Baroclinicity/Baroclinic Zone is the temperature difference over a short distance which allows for the formation of Low Pressure Sytems)

With regards to the GFS, the shortwave over Alaska is significantly more energized. This, in turn, injects not only more energy into the TCV, it also changes the momentum. It's physics. Think of it like this: If a vehicle is traveling at a relatively slow rate of speed, turning the steering wheel will produce a much gentler turn. Whereas, if a vehicle is moving at a high rate of speed, cutting the wheel will produce a more dramatic effect/turn. With the GFS, the vehicle is way over the speed limit. With some of the other models, the vehicle is traveling much slower. 

One more note - there are a plethora of studies on how TPV affects downstream weather (IE, the Lower 48). All of them, however, come to 2 conclusions.

1) Stick to Ensembles as they are better versed to handle the spread caused by the dynamics of this particular weather phenomena.

2) TPV interactions are notorious for forecast busts, especially 6+ days out. 

NOTE: The Graphic included below illustrates the TCV . The air is rotating around the North Pole and the red bold line are the outer edges of the TCV. The Green which shows within the blue is an example of a TPV. This is a good illustration of how the TPV can be -and is- affected by the TCV and other energies within the TCV.

Remember - Weather is the physics of the interconnected atmosphere of the planet we live on. Everything is intertwined.  

[Pros3lyte]

2 minutes ago, Uscg Ast said:

My 2 Cents:

From what I can see, it appears that the TPV (see below) is being affected by a shortwave in Alaska which is impacting the tropospheric circumpolar vortex (TCV - Please see picture below for additional assistance as I explain), which in turn is altering how the TPV itself is manifesting, thus changing the baroclinic zones and allowing for bombogenesis near the Midwest rather than the EC. So.. let me break that down. 

 

The TPV is known as the Tropopause Polar Vortex. We will get to this in a minute, however, let's start with the TCV.  The TCV is a large rotating column of air which is loosely wound around the Poles. In our case, we are affected by the one rotating around the North Pole. This loosely rotating column of air is centered on the North Pole and can reach as far South as the Southern United States, though this Southern boundary tends to fluctuate between Canada and the Southern US (this is a bird's eye view explanation. There are some very technical and intricate features which I am glancing over). 

 

That being said, let's get into the TPV. The TPV is what most people think of when the Polar Vortex is mentioned (ie media, public, etc). What a TPV actually is, is a lobe within the TCV. Basically, It is a HP System which forms within the rotating column of air that is the TCV. When this lobe develops, it is normally what is responsible for an Artic Air Intrusion into the United States. The thing about TPVs is that they are rather susceptible to other energies within the TCV. 

 

In this particular case, the TPV is being affected by a vigorous piece of energy over Alaska. This piece of energy (a shortwave) is still poorly sampled and -as mentioned previously- is in no man's land Alaska. The difference in the current models appear to be attributed to this shortwave feature. What appears to be happening is that the models which are keeping the shortwave less vigorous are thereby keeping the TCV with less perturbation (or ridges and troughs - ie more zonal). This zonal flow allows the TPV to settle further into the center of the country. In other words - the more zonal flow changes the momentum and thus where the artic air intrusion first begins. In turn, this changes the baroclinic zone and therefore where the Low-Pressure System eventually sets up. (Baroclinicity/Baroclinic Zone is the temperature difference over a short distance which allows for the formation of Low Pressure Sytems)

With regards to the GFS, the shortwave over Alaska is significantly more energized. This, in turn, injects not only more energy into the TCV, it also changes the momentum. It's physics. Think of it like this: If a vehicle is traveling at a relatively slow rate of speed, turning the steering wheel will produce a much gentler turn. Whereas, if a vehicle is moving at a high rate of speed, cutting the wheel will produce a more dramatic effect/turn. With the GFS, the vehicle is way over the speed limit. With some of the other models, the vehicle is traveling much slower. 

One more note - there are a plethora of studies on how TPV affects downstream weather (IE, the Lower 48). All of them, however, come to 2 conclusions.

1) Stick to Ensembles as they are better versed to handle the spread caused by the dynamics of this particular weather phenomena.

2) TPV interactions are notorious for forecast busts, especially 6+ days out. 

NOTE: The Graphic included below illustrates the TCV . The air is rotating around the North Pole and the red bold line are the outer edges of the TCV. The Green which shows within the blue is an example of a TPV. This is a good illustration of how the TPV can be -and is- affected by the TCV and other energies within the TCV.

Remember - Weather is the physics of the interconnected atmosphere of the planet we live on. Everything is intertwined.  

Awesome! Thanks for breaking it down so well. These kinds of posts are the main reason I frequent weather forums!