Long Range Discussion 20(20) (Ha!)

Potential January 8th storm:

Pros

*Developing west based -NAO
*Possible 50/50 Low

Cons

*-PNA
*No polar jet interaction or northern stream phasing which risks the coast being too warm



Potential January 12th storm:

Pros

*Full phase with northern and southern jets
*Established west based -NAO
*Developing +PNA
*Colder air mass than possible 8th storm

Cons

*Pacific continues to be an issue, and no guarantees the PNA comes to fruition. This would derail a phase and keep colder air away from the coast

The EURO shows a very ominous coastal low off the coast for the 8th. It actually shows a phase due to a pseudo +PNA ridge that evolves ahead of a shortwave coming into the west coast. That’s one way to make things super interesting!

If these two pieces of energy can phase/merge cleanly probably looking at a MAJOR snowstorm for the area.  This is close but they don't phase cleanly. However, don't even think the models will figure this out for several days. Even with a non clean phase it could still drop sig snow for the area.


Note the pictures and how in the second the trough completely goes negative.

DO NOT UNDERESTIMATE THE POWERS OF THE SNOW QUARTERT !! AND THE NAO / AO COUPLET LOL!!
You have a potent PAC JET screaming off the Tibetan Plateau and you are starting to see kinks in the JET as it approaches the NAMER. The heights are spilling off of a very strong block in the AO/NAO region towards the AK region. The SW are just going to rolling in every 4-5 days like a perfectly spaced traffic pattern as you try to turn out of the schools parking lot at dismissal time. The NAO is purely West based and looking at analogs we have 2009,2010,1977, 1995 dare I say analogs for such a block. The models will come around as they move up in time. Buckle up.peeps its going to be fun tracking ~4 day possible storms. As I have said since early Dec, you don't need Polar Arctic Air for snow but rather air that is just cold enough period. Hopefully everyone can cash in but no crying, you have a better winter already than the last 2!

I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

@heehaw453 wrote:I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

With the incoming anomalous setup occurring in the coming days it’s only a matter of time before we get slammed. Once the PAC straightens itself out, the pattern will scream HECS potential.

The 1/11-/12 period looks to have better wave spacing and is a window of opportunity for now. It's very hard to nail anything down as there are just too many short waves flying around to say this is the one. I do think though the upper air pattern is more favorable during that time.

@heehaw453 wrote:I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

We have the ukie and navy model on board. The UKie has been pretty consistent so far with this making it into our area

@heehaw453 wrote:The 1/11-/12 period looks to have better wave spacing and is a window of opportunity for now.  It's very hard to nail anything down as there are just too many short waves flying around to say this is the one.  I do think though the upper air pattern is more favorable during that time.

Agree

I’m not writing off any potential before 1/10 yet. Keep in mind models won’t have proper sampling of all this PAC energy until just a few days before the storm would affect us. We could see drastic changes in model runs for some events, including the one on 1/7.

@heehaw453 wrote:I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

That piece of energy that is up on Maine or SE Canada that suppresses the heights and the storm into the Mid Atlantic breaks off from the Alaska Low and traverses all of CAN. Have to see if that is real in the next few days or not. That Vort is in la la land.
11/12th
15/16th

EPS - just south

@amugs wrote:

@heehaw453 wrote:I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

That piece of energy that is up on Maine or SE Canada that suppresses the heights and the storm into the Mid Atlantic breaks off from the Alaska Low and traverses all of CAN. Have to see if that is real in the next few days or not. That Vort is in la la land.
11/12th
15/16th

EPS - just south

I agree with you. It's common though to have energy thrown around from up north during the -NAM state. I think they'll be northern energy, but it's a question of where it sets up. I think in 36 hours we'll know a lot better. But most model ensembles insist on this bad setup.

@sroc4 wrote:

@amugs wrote:

@heehaw453 wrote:I'll give the 1/9 threat until Wednesday 0Z before I write it off.  This vortex to the north cannot be on top of the southern short wave at that latitude for this storm to have any chance to affect this area.  It must be behind the storm to give the southern short wave room to come up or far enough north (Central Quebec) such that there is room. If it can get behind it and tug it westward then this would be a MAJOR storm for us.  If there is no northern stream interaction then it would probably be a minor event.  

This is one shortwave out of many that will roll through here in the next several weeks with an increasingly better PAC and -AO/-NAO.  Not to be discouraged if this low chance event misses.

That piece of energy that is up on Maine or SE Canada that suppresses the heights and the storm into the Mid Atlantic breaks off from the Alaska Low and traverses all of CAN. Have to see if that is real in the next few days or not. That Vort is in la la land.
11/12th
15/16th

EPS - just south

It literally traverses N Canada across the Hudson Bay and runs into the block.  The block treats it like a tennis racket and tennis ball and smacks it strait south into northern NE which prevents our pot system from coming up.

Yup

In my earlier post I incorrect said 1/7. 1/9 is the date to follow, along with 1/12 to 1/13.

So much energy! The pattern before 1/15 offers plenty of energy but very little in the way of Pacific ridging (PNA/EPO). The time frame after 1/15 it looks like we'll see Pacific ridging come into the fold.

One of the more robust -NAO patterns we have seen in awhile on the latest GEFS. Very strong signal near 1/12 with an established -AO/-NAO.



Keep an eye on these trends. Today's GEFS amplified the H5 pattern to show deeper trough and higher heights along the west coast.





​​​​​​​

I raised the SCI from 5% to 10% for January 12th after seeing today's 12z EPS. Anytime there is a ridge bridge between the west coast and arctic that spells trouble for east coast snowstorms. And by trouble I mean Godzilla! Madonne what a look.

Mean zonal winds at 10 hPa in the Stratosphere have reversed to westerly and will enter a 15 day stretch of keeping to that direction. A major SSWE will displace the Strat off the pole and is cause for the upcoming anomalous -AO/-NAO pattern. There is a chance for a second warming event in the middle of the month, which would split the PV into two pieces which would mean great things for the month of February. However, as you can see zonal winds try to return back to easterly after the 15-day stretch. I would not look out so far just yet. These maps changed drastically by the day.

@Frank_Wx wrote:I raised the SCI from 5% to 10% for January 12th after seeing today's 12z EPS. Anytime there is a ridge bridge between the west coast and arctic that spells trouble for east coast snowstorms. And by trouble I mean Godzilla! Madonne what a look.

That's dramatically better than 1/9.  The 12th period has my full interest too.

I know the models have backed off the storm threat for 1/12, but believe me this upper air pattern is suggestive of a storm.  It's all about wave spacing.  This trailing northern piece over MN with the ridge is what you want to see. The reason they have backed off the storm is the northern piece just over Michigan which prevents the trough from rounding the corner by squashing the heights and flattening it out.

With the -AO state you get these spinning vortexes coming down from the arctic very frequently. They are sometimes the reason you gets 1'+ of snow and sometimes the reason you get OTS with suppression. Still a very viable threat IMO, but it's going to come down to wave spacing.

1/ I pointed this out in the yesterday's blog. I don't recall ever seeing the maximum of positive polar cap geopotential anomalies successfully complete a "U" shape in the stratosphere before. I know this is complicated but potentially very significant. pic.twitter.com/tPDuykTgvg

— Judah Cohen (@judah47) January 5, 2021

This screams Polar Vortex Disruption that could have 30-60 days affects if it lasts this long

Some exciting model runs today. The event on 1/12 or 1/13 is legit and has to be watched closely. I’m keeping the SCI at 10% for now, but could raise it tomorrow.

The event on 1/9 is not going to pan out.

Also, the mobile version of this forum is so much better than trying to use the desktop version on your phone. It only took me three years to figure that one out.

Today's 12Z Euro is a bit more what I was hoping for. Don't care how the run finishes or thermals at this point. The northern stream this time phases in with the southern trough and there is no suppression. It has the making of a big one.

@Frank_Wx wrote:Also, the mobile version of this forum is so much better than trying to use the desktop version on your phone. It only took me three years to figure that one out.

Mobile version, meaning there's an app?

@essexcountypete wrote:

@Frank_Wx wrote:Also, the mobile version of this forum is so much better than trying to use the desktop version on your phone. It only took me three years to figure that one out.

Mobile version, meaning there's an app?

No app.

But if you’re on the desktop version using your phone, in the bottom right of the page you should see a mobile version option. If you’re already using mobile version then in the upper right you should see a menu where you can select web version. But mobile >>> web

What happens when mainstream media tries to report the weather? You get bizarre, ridiculous headlines like this

https://www.washingtonpost.com/weather/2021/01/05/polar-vortex-split-cold-snow/?outputType=amp