Re: Long Range Thread 25.0

[heehaw453]

Synoptically AccuWeather is spot on with the threat area.  Unfortunately there's not cold air in good supply, so my guess is the blue shaded area will dramatically change with the next update.

https://cms.accuweather.com/wp-content/uploads/2023/01/SnowPotLtNxWkEastChan5Jan.jpg?w=632

[sroc4]

So I've been monitoring the MJO forecasts because there has been enthusiastic talk about it finally coming out in the favorable phases of 8 and propagating from 8-1-2 which would be great for a trough in the east and multiple snow threats.  But as Im about to show the trend since the 2nd of the year has been less and less amplitude with time, and perhaps not even coming out in 8 at all.  The trend for when it comes out of the center is more towards the 8-1 line just outside the center/null phase. My concern would be if this trend conts then the MJO really wont actualy pulse out of the circle of death COD.  

NOTE:  First Euro MJO forecast Then GFS.  And if you need a refresher or are unsure exactly what the MJO is click the link below.  

https://www.njstrongweatherforum.com/t511-what-is-the-mjo-really

EURO




GFS








Now two things:
First this is only the trend Im pointing out here.  In general the greater the amplitude the more influence the MJO can have on the atmosphere.  The less amplitude equals less influence on the big picture potentially allowing other things to over-ride its effects.  Less amplitude doesn't mean that it wont have an effect.  It's always the sums of all the parts.  For the recod the further away from the center of these graphs equals greater amplitude; the closer to the circle the less the amplitude.  Inside the Circle equals null phase.  

Second, over the past couple few weeks, the La Nina cold SSTA in the trop Pac have been very slowly beginning to warm POTENTIALLY hinting that the La Nina may actually be weakening.  That said maybe if the MJO does comes out in phases 8-1-2 there may be a positive outcome regarding cold and snow chances, despite it being with very little amplitude, because the La Nina background state "may" be letting up a bit....at least with regards to the SSTA in the ENSO.  But we need to be cautious with this.   As I have stated in a prev. post there have been a couple of potential times since last winter that the Trop Pac has hinted at the possible weakening of the La Nina, but those attempts have been mere head fakes.  Every time the SSTA begin to warm mother nature has said "nah...not yet."  






Currently the SOI(https://www.longpaddock.qld.gov.au/soi/) continues to crank away in the upper teens and 20's.  This tells me the atmosphere is not yet out of that Background Nina state.  Is the subtle warming of the trop Pac so far this month compared to Dec and November another head fake or is this finally the true end to 3 consecutive mod La Nina's?  Time will tell.  As you can see below; however, Nino region 3.4 has taken another significant cold dip after seemingly on the rise.  

[sroc4]

One final thing. These are the EPS and GEFS 12z runs today valid for the very end of their runs depicting the 22nd. Again the LR has looked great only to find reality sucking. Euro looks great, GFS ehh. Lets see what both of these look like in a week or so. How will it evolve?

[heehaw453]

This maybe why AccuWeather has the snow threat the way they do for now.  With this setup there's a chance.  We don't know how quickly the ULL develops.  If it develops less rapidly due to less stream interaction then this setup will produce snowfall.  If there is no 50/50 low or that H is not as robust forget about it.  If the storm rapidly intensifies while over MO or TN forget about it.  But if it doesn't and there is this setup then there will be snowfall especially over the interior.  Yes thread the needle, but not 0 chance either.

[amugs]

"If it walks like a duck, quacks like a duck, it's a duck." Models reversing & now showing a stretched #PolarVortex/wave reflection that brings colder weather to eastern North America. #MachineLearning model (has some timing issues) but has trended colder in East US for late Jan. pic.twitter.com/WMeVpJm6kv

— Judah Cohen (@judah47) January 8, 2023

[sroc4]

Euro added a little wrinkle for late week. Possibly two waves. First one torches but gets the front through, followed by a second wave that rounds base of the trough and rides the front. Almost like two storms from same trough. Not too worked up but something to watch I suppose.

[sroc4]

Euro added a little wrinkle for late week. Possibly two waves. First one torches but gets the front through, followed by a second wave that rounds base of the trough and rides the front. Almost like two storms from same trough. Not too worked up but something to watch I suppose.

First time seeing the SOI in single digits in quite some time. Id like to see it lower though for like 5days. Throw in a few negative numbers. That said perhaps a few more days in single digits could imply the atmosphere is easing up a little. Perhaps.

[heehaw453]

Euro added a little wrinkle for late week. Possibly two waves. First one torches but gets the front through, followed by a second wave that rounds base of the trough and rides the front. Almost like two storms from same trough. Not too worked up but something to watch I suppose.

Yep.  That's been showing up as a possibility but I doubt it because the trough isn't a good negative tilt and there's not a 50/50 to slow things down.  My thought is the energy slides off the coast similar to a frontal passage.  Maybe some mood flakes though?

[sroc4]

Euro added a little wrinkle for late week. Possibly two waves. First one torches but gets the front through, followed by a second wave that rounds base of the trough and rides the front. Almost like two storms from same trough. Not too worked up but something to watch I suppose.

Yep.  That's been showing up as a possibility but I doubt it because the trough isn't a good negative tilt and there's not a 50/50 to slow things down.  My thought is the energy slides off the coast similar to a frontal passage.  Maybe some mood flakes though?

Don’t get me wrong simply going by how this winter has gone so far it’s hard to make any kind of argument that this will work. I certainly realize that. But I sticking with my theme from yesterday regarding optimism, when looking at this set up there are two things that seem different.

First if you run the 500mb vort maps back and forth on a look you see that on all three majore models the timing of the Pac energy behind our ridge seems to suggest amplification of our ridge as our first wave of LP passes well to the west. This gets the frontal boundary to the coast. Now exactly where we’ll still a bit of differences. Because the ridge is amplifying this will allow that second wave of energy to drop into the base to generate a second wave of LP along the boundary.  




If you look at the EPS mslp maps you can see this take place between hrs 108 and 114. Literally a group of LP pops. There is still a large spread so take it with a grain of salt. But again if timing of ridge amplification and secondary LP along the boundary is right it’s possible.






The second thing I’m looking at that MAY indicate there could be a slight differ outcome is that SOI data. I mentioned above for the first time in a long time we have a single digit. If you look at the 500mb height anomaly maps of the Pacific Basin, over the next 5-7days there appears to be higher height anomalies showing up consistently in the area of Darwin Australia when compared to Tahiti. I have been monitoring this and the absolute SOI values all season and I can tell you there have been negatives over Darwin almost the entire season; certainly over the past month. This appears to be a significant change for this upcoming 5-7day time frame from the past month. If the 500mb anomaly maps are correct then the SOI value will persist in at least single digits if not lower which MAY affect how the atmosphere behaves down stream. It may mean nothing and we more likely than not still end up with oogatz out of this. But if you are looking at this set up from the optimistic side of the box, there are a couple of things to keep an eye on here. We are officially under 4-5.5 days from this event so it’s not like it’s long term.  we’ll see. We track.

[heehaw453]

You bring up good aspects sroc.  Personally I lost interest in this one once the 50/50 was off the table. That was our shot IMO to get some front end stuff especially if the H was 1038+. I was also seeing some possibility of energy running out ahead of the system to tap into that air mass before the warmup.  But let's see if models continue to latch onto this idea.  Will be nice to catch a break.

[MattyICE]

So would we want to see even more initial amplification on the front end to help slow the trough down a bit as it hits the coast? Allowing secondary energy to consolidate at the base? I feel like several models hint at this but most likely to far NE of us as the ridge rolls eastward as the next PAC storm knocks on the door.

[heehaw453]

So would we want to see even more initial amplification on the front end to help slow the trough down a bit as it hits the coast?  Allowing secondary energy to consolidate at the base?  I feel like several models hint at this but most likely to far NE of us as the ridge rolls eastward as the next PAC storm knocks on the door.

Matty from my perspective I don't see anything in the 50/50 area to slow a developing storm down and I don't see a good leaning negatively tilted trough to throw good moisture back to the coast after the initial Low passes on by.  If the ULL blew up more than that could tilt the trough more.

[Wheezer]

Appreciate the analysis even when an event isn't exceptional. A lot of us lurkers still want to learn the nuts and bolts of the meteorology behind it

[sroc4]

So would we want to see even more initial amplification on the front end to help slow the trough down a bit as it hits the coast?  Allowing secondary energy to consolidate at the base?  I feel like several models hint at this but most likely to far NE of us as the ridge rolls eastward as the next PAC storm knocks on the door.

Prob that and/or well timed ridge amplification which would allow the secondary wave to dig and amplify out ahead and the primary wave be there to prevent overamplification along the coast.   Its interesting to to me to see how the Pac energy initially triggers the Ridge amplification out ahead, but once its hits the WC, and likely interacts across the Rockies triggering vertical turbulence do to the upsloping on the west side and down sloping on the east, which then triggers the collapse of the ridge.  Again this doesn't seem to happen until the energy comes ashore west of the ridge.  When the NE Atlantic is less than ideal, the timing of these things out west seems critical.

[heehaw453]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

[sroc4]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

Man Euro looks inviting.  So close, so very close.....Damn you models.  Why do you tease us so??????

https://images.weatherbell.com/model/ecmwf-deterministic/conus/vort500_z500/1673265600/1673740800-mBaBckdrSPg.png

[amugs]

EURO says I'll hold back the energy, weaken the primary and transfers most of the energy to the secondary which comes of VA/NC border and deepens. It has enough separation and time as the front swings on in to produce snow to the NW of NYC Metro.
Interesting set up and have seen these trailing vorts blow up before after the front moves through. Timing and space are crucial to this. And you see a Banana High forming as well to help reinforce the cold air.


Brooklynwx from 33nrain map

[heehaw453]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

Man Euro looks inviting.  So close, so very close.....Damn you models.  Why do you tease us so??????

https://images.weatherbell.com/model/ecmwf-deterministic/conus/vort500_z500/1673265600/1673740800-mBaBckdrSPg.png

 I'm not getting sucked in again   Too much of emotional roll coaster  Who am I kidding though 

[heehaw453]

Right here the ULL closes off.  If it closes off and deepens before hitting the coast then watch out.  Then someone between DC-BOS would be getting 6"+ of snow.

[docstox12]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

Man Euro looks inviting.  So close, so very close.....Damn you models.  Why do you tease us so??????

https://images.weatherbell.com/model/ecmwf-deterministic/conus/vort500_z500/1673265600/1673740800-mBaBckdrSPg.png

One of them has to be CP.

[sroc4]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

Man Euro looks inviting.  So close, so very close.....Damn you models.  Why do you tease us so??????

https://images.weatherbell.com/model/ecmwf-deterministic/conus/vort500_z500/1673265600/1673740800-mBaBckdrSPg.png

One of them has to be CP.

After crawling around the bushes and the weeds, fortunately undetected, over at OTI hearing some of the conversation over there I have no doubt Doc....no Doubt.  LOL.  But shhhhhh.  Please don't tell him I was over there hiding out in the bushes.  I would like to stop by again and perhaps say hello and have a coconut cocktail.  Hopefully he's not too mad at me and my perpetual optimism.  I cant help it.  It is my minds way of dealing with the "madness of my misery" from lack of cold and snow.

[heehaw453]

We need to see better ensemble support for closed off ULL around OBX/Va Beach.  This is D4+ so if it's real the next 24 hours there will probably be much better ensemble support than what we got now which is too much spread.

[heehaw453]

GFS ULL disorganized and doesn't close off. GFS scenario the energy just gets pushed out to sea. Note the difference between Euro top and GFS bottom. Euro has a slightly better ridge and less trough interference to the west that probably makes the difference. I think next 24-36 hours the sh#t either real or it's not.  I say no until I see more consensus as that damn PAC flow is a thorn in rear.

[sroc4]

GFS ULL disorganized and doesn't close off. GFS scenario the energy just gets pushed out to sea. Note the difference between Euro top and GFS bottom. Euro has a slightly better ridge and less trough interference to the west that probably makes the difference. I think next 24-36 hours the sh#t either real or it's not.  I say no until I see more consensus as that damn PAC flow is a thorn in rear.

Also notice the trough is a bit faster to hit the west coast on the GFS compared to the Euro.   The trough on the EC is open and positive tilted.  Oogatz if that's the result for sure.  I will say over the years the GFS's bias has been that's its a progressive model FWIW.   I agree there is no way Im jumping the gun on this one.  Tamping down our ridge at inopportune times has been a major Achilles heal all winter, so until I see it play out otherwise that's my expectation...for now...too.  Most of the southern energy comes on shore tomorrow so 12z tomorrow and def 00z over night Tuesday should have solid data input.

[heehaw453]

We got the Icon on board with one hell of an ULL deepening  

[Frank_Wx]

Really nice look on the 18z EURO. It feels like we're gaining some momentum. Would love to see the 00z GFS step toward this idea tonight

[jmanley32]

The Canadian model shows well what sroc was talking about.  You get the ULL to close off at that latitude.  That would blow up surface low pressure and slow it down.  W/out a complete close off of the ULL I can't see something like this as the Atlantic flow is too progressive.  I would want to see a more negatively tilted trough too.

Man Euro looks inviting.  So close, so very close.....Damn you models.  Why do you tease us so??????

https://images.weatherbell.com/model/ecmwf-deterministic/conus/vort500_z500/1673265600/1673740800-mBaBckdrSPg.png

One of them has to be CP.

Duh the tweeker right up front lol, just playing CP, but from how upset you get it's the first one that hit me lmao.

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