Jan/Early Feb Medium/Long Range Discussion Part 3

[Bob Chill]

13 minutes ago, psuhoffman said:

No you’re right. The pac jet has been on roids lately. Ever since 2016. Best theory I’ve read is the expanded Hadley cell is compressing the jet and amplifying it.  So now when the jet extensions happen it’s not just warm it’s an ungodly torch across the whole continent.  
 

The problem is that’s still the loading pattern for our best snow pattern. We need those jet extensions to get to the canonical -nao -epo look that leads to most of our truly snowy periods.  That awful pattern starts the chain reaction and wave breaking that leads to what we want. But lately we waste a big chunk of the better pattern when it comes because it’s so warm leading in. So warm that often the SER just links with the -nao and it does us no good at all. 

Thought provoking.... It's safe to say based on observation that the long range models are being tricked by this. Always quick to break it down in the long range only to back off an add a week as time rolls lol. Ish has been stuck on repeat lately lol. 

Brings up another thought. Maybe March being more wintry is a byproduct of this. Wavelengths all over the NH go through a transition and shortening period in late Feb thru March. Pac jet behavior included. Worth a look. I'm expecting a notable part of March to be more of a lion than lamb now. If we're going to keep having the same problems midwinter, maybe we keep getting the same bonus period late. 

[CAPE]

21 minutes ago, psuhoffman said:

Pac jet extensions are going to happen every winter. This isn’t some crazy rare thing. But lately we take weeks to recover. That’s the part that’s killing us and historically it’s not normal. Some of the best analogs to this winter a jet extension just like that set off the chain reaction that lead to a snow run. Usually a -pna comes before a blocking regime!  But the snow wasn’t a month later. It’s was days to maybe a week at most later. We didn’t take weeks to recover. That’s what really killing is lately, the progression that historically leads to our best snow pattern is torching the continent so bad that we end up wasting most of the good pattern when it comes!  

The primary jet core is actually retracted at this point-

 

Right at the end of run the jet core is strengthening/starts to extend. Roll that forward and that ridge axis should be positioned further eastward along the west coast of N America.

 

 

[CAPE]

Simplified explanation- The left exit region of the jet core = strong speed divergence, so low pressure at the surface and an h5 trough. Ridge out in front. If the desired result is a +PNA, we want an extended jet to shift the trough/ridge eastward some. If it extends too much, trough approaches west coast and PNA ridge shifts into central US. Delicate balance.

[aldie 22]

0 weeks of winter in December 1 week in January 1 week in February and 1 week in March? Ok so 8-10" in January 15-20" in February and 30" in March...solid 3 weeks worth of winter 

[Bob Chill]

1 hour ago, CAPE said:

Simplified explanation- The left exit region of the jet core = strong speed divergence, so low pressure at the surface and an h5 trough. Ridge out in front. If the desired result is a +PNA, we want an extended jet to shift the trough/ridge eastward some. If it extends too much, trough approaches west coast and PNA ridge shifts into central US. Delicate balance.

Always a dam delicate balance lol. I don't like how intrusive the extensions are. The more I think about it the more it makes sense given the last 6 years of so. That balance is off for some reason as psu posted earlier. I'm going to pay much closer attention as lr guidance is consistently underestimating the extent of the intrusion. Feb is a deep winter month so may this time it progresses more traditionally.

Maybe this is part of the new March effect. When wavelengths shorten,  maybe the pac jet backs off of roids and ends up popping a correct +PNA instead of a convoluted flow ridge like we keep seeing. Idk man. Our problems seem more consistent to me as enso doesn't seem to change things all that much irt the ripping pac jet. Honestly, "traditional patterns" are becoming untraditional. Winter forecasts are consistently being upended. Even people who get US temps and snow right don't get it they way they explained but it verifies anyway lol

[CAPE]

12 minutes ago, Bob Chill said:

Always a dam delicate balance lol. I don't like how intrusive the extensions are. The more I think about it the more it makes sense given the last 6 years of so. That balance is off for some reason as psu posted earlier. I'm going to pay much closer attention as lr guidance is consistently underestimating the extent of the intrusion. Feb is a deep winter month so may this time it progresses more traditionally.

Maybe this is part of the new March effect. When wavelengths shorten,  maybe the pac jet backs off of roids and ends up popping a correct +PNA instead of a convoluted flow ridge like we keep seeing. Idk man. Our problems seem more consistent to me as enso doesn't seem to change things all that much irt the ripping pac jet. Honestly, "traditional patterns" are becoming untraditional. Winter forecasts have been consistently being upended. Even people who get US temps and snow right don't get it they way they explained but it verifies anyway lol

The NPAC jet is ever-present and upstream so it has a major influence on the pattern. If it is stronger now/ going forward, then it will run the show even more. Frequent and longer lasting HL blocking episodes would help to mitigate the Pacific issues. We need a 1960s-like streak lol.

[Weather Will]

I am going to remain optimistic for February.  Looking at the GFS on the 6th, it may be above normal in Canada, but cold enough....edited to add WB 6Z GEFS.

[Chris78]

I wouldn't sleep on next Sunday 

[Maestrobjwa]

2 hours ago, psuhoffman said:

No you’re right. The pac jet has been on roids lately. Ever since 2016. Best theory I’ve read is the expanded Hadley cell is compressing the jet and amplifying it.  So now when the jet extensions happen it’s not just warm it’s an ungodly torch across the whole continent.

BADley cells. That's what they are...BADley. I am growing to detest those wretched things! Boo. BOOOO Hadley...BOOOOOOOO!

[WxUSAF]

4 minutes ago, Chris78 said:

I wouldn't sleep on next Sunday 

GFS is verbatim an example for Hoffman’s book with a perfect track at peak climo with a torched boundary layer.

 

[Terpeast]

11 minutes ago, WxUSAF said:

GFS is verbatim an example for Hoffman’s book with a perfect track at peak climo with a torched boundary layer.

 

For now it’s way too warm, but there’s a cold high lurking to the north. It won’t take much of a favorable trend to flip this into our favor

[Heisy]

Wxusaf,

12z OP GFS has the progression you pointed out. It’s also been on the weeklies too. The ridge migrates east and then eventually into the right places. We will torch a few days between now and then but whatever. Roll second image up in time we probably have a decent pattern





.

[brooklynwx99]

24 minutes ago, WxUSAF said:

GFS is verbatim an example for Hoffman’s book with a perfect track at peak climo with a torched boundary layer.

 

i don't think this would have snowed in 1873 with this antecedent airmass

[brooklynwx99]

3 minutes ago, Heisy said:

Wxusaf,

12z OP GFS has the progression you pointed out. It’s also been on the weeklies too. The ridge migrates east and then eventually into the right places. We will torch a few days between now and then but whatever. Roll second image up in time we probably have a decent pattern





.

yeah you're getting that trough to roll under the ridge and lead to wave breaking. it's moving forward in time and is supported by extended guidance so it seems legit for now

[osfan24]

5 minutes ago, brooklynwx99 said:

i don't think this would have snowed in 1873 with this antecedent airmass

I think his point is the air mass wouldn’t have been that torched in the past during late January, especially when it was very cold a week prior.

[brooklynwx99]

1 minute ago, osfan24 said:

I think his point is the air mass wouldn’t have been that torched in the past during late January, especially when it was very cold a week prior.

i'll have agree to disagree on that one

[jayyy]

Please stop posting garbage in the long range thread. There is a banter thread

Sent from my SM-A515U using Tapatalk

No offense, but you’re probably the last person that should be telling people where to post their banter / panic room rants. If you’re going to take a shit in every thread, then don’t bash others for trying to be optimistic. Think it’s fair that you either both are allowed to “post garbage” or you both take it elsewhere.

[jayyy]

I think his point is the air mass wouldn’t have been that torched in the past during late January, especially when it was very cold a week prior.

I’m from a place that’s much colder and snowier than here, and I can for sure tell you that temps in the 50s and above have without a doubt occurred after deep freezes, even in mid winter. That’s nothing new, ESPECIALLY for our CWA. However, there is a point to be made on the opposite side of that IE: it’s taking longer to get cold once unfavorable patterns break down.

My thought is that it doesn’t take as long this time because cold air is finally on this side of the globe and there’s been cold / snow to our north and up in Canada. Yes, it’ll melt and get warm up there too, but I don’t think we take weeks on end to get cold again. Colder air, while locked away up north, won’t be on the other side of the globe and we will be in mid winter, not early winter. I might be wrong, but that’s my hunch.

[psuhoffman]

57 minutes ago, brooklynwx99 said:

i don't think this would have snowed in 1873 with this antecedent airmass

I couldn’t disagree more. We used to get lots of little flaws snow events in horrible patterns. Why do you assume that pattern would produce that level of torch 50 yrs ago?  From my experience it didn’t. As recently as 2010 we had the exact same pattern and lt didnt torch the continent that bad! The pac jet is stronger now and is leading to worse air masses. 

[brooklynwx99]

4 minutes ago, psuhoffman said:

I couldn’t disagree more. We used to get lots of little flaws snow events in horrible patterns. Why do you assume that pattern would produce that level of torch 50 yrs ago?  From my experience it didn’t. As recently as 2010 we had the exact same lagger and lt when torch the continent that bad! The pac jet is stronger now and is leading to worse air masses. 

even if you slice the positive anomalies in half, you don't want a +6C airmass heading into any kind of snowfall event. it likely wouldn't work regardless. for as many flawed snow events, we also got a shit ton of rain, but nobody cares about the 8/10 times that it rained in these kinds of patterns

fair, I get your overall point, but that's not a setup that would have worked in a long time. it's too warm leading in

[Terpeast]

So this might go in banter or panic room because this is purely unscientific conjecture…

But if the pac jet is getting stronger with a hadley cell squeeze no matter in a nina or nino, what should we root for? 

More ninas where the jet doesn’t get as super extended as in ninos, but still extended enough to stick a pna ridge in the west? 

Last time we tried that though, we got a +PNA but the downstream trough dug right underneath into baja, and the pna ridge just flopped over right on top of us. Maybe that was just a one off?

I know in ninas we get an Aleutian ridge which is usually kiss of death for us, but it shouldnt take much of an extension to push that ridge over the top into AK and drive more cold air down here? It can’t be that hard

[fujiwara79]

For early February, The GFS keeps spitting out solutions that look more like mid April.  Cut-off lows that spin around aimlessly in the Rockies, giving them a pasty wet "spring snow" while the rest of the country is showery.  Looks like a spring pattern.  Yuck.

[WxUSAF]

 

[DarkSharkWX]

nice recovery

[Daniel Boone]

1 hour ago, fujiwara79 said:

For early February, The GFS keeps spitting out solutions that look more like mid April.  Cut-off lows that spin around aimlessly in the Rockies, giving them a pasty wet "spring snow" while the rest of the country is showery.  Looks like a spring pattern.  Yuck.

With the Strat deal , there's going to be wonky solutions upcoming. 

[clskinsfan]

1 hour ago, Terpeast said:

More ninas

I will never root for a NINA. Never. Maybe ENSO neutrals will be the winner for us going forward?

[TSG]

1 hour ago, fujiwara79 said:

For early February, The GFS keeps spitting out solutions that look more like mid April.  Cut-off lows that spin around aimlessly in the Rockies, giving them a pasty wet "spring snow" while the rest of the country is showery.  Looks like a spring pattern.  Yuck.

 

13 minutes ago, Daniel Boone said:

With the Strat deal , there's going to be wonky solutions upcoming. 

Might be memory bias on my part but I think it was doing similarly weird things late Dec/early Jan when this past week's pattern was coming over the horizon. And we did get a couple massive mid-continent storms/cutters before the current cold

[Ralph Wiggum]

3 hours ago, Chris78 said:

I wouldn't sleep on next Sunday 

 

[psuhoffman]

58 minutes ago, clskinsfan said:

I will never root for a NINA. Never. Maybe ENSO neutrals will be the winner for us going forward?

Neutrals since 2000 have pretty bad. 5/6 below normal snow. 

[Jebman]

2 hours ago, jayyy said:

No offense, but you’re probably the last person that should be telling people where to post their banter / panic room rants. If you’re going to take a shit in every thread, then don’t bash others for trying to be optimistic. Think it’s fair that you either both are allowed to “post garbage” or you both take it elsewhere.

I deleted it then took it to banter. I should know better. Back to model disco.