2023 - tracking the tropics

[Damage In Tolland]

Here she comes! 

[WxWatcher007]

1 hour ago, WxWatcher007 said:

The NHC has designated our AOI in the eastern Atlantic as Invest 95L. It already has a good look to it, with significant spin and some disorganized convection. 

 

Normally, I am more muted when we're at the invest stage, but not this time. I believe this is the strongest signal we've seen for a long track CV major hurricane in quite some time. 

Why? The environment ahead looks tremendous not just for tropical genesis but significant intensification in the MDR. 

First, it's the moisture. Unlike early August, where SAL and subsidence dominated the MDR, we have a more moist and unstable environment thanks to the presence of much stronger preceeding waves scouring out the SAL. 

Look at the dramatic rise in instability in the MDR since August. It's more than enough, as we've seen. 

Obviously the thermodynamic environment is excellent. We have strong SSTs and OHC through the MDR and basin. 

With a strong ridge building in over the Atlantic, wind shear should initially be low. That alone is enough for TC genesis. There is a long runway of low shear in the MDR.

(Edit: there are low trades initially, which means easterly shear, but I don’t think this will disrupt progression much after a few days)

However, what sets this apart from other setups, especially in recent years, is that it looks like the orientation of the steering pattern is going to create ideal conditions for ventilation. 

From Eric Webb

Folks, that's big time. All systems seem poised to allow for TC genesis, followed by an increasing level of organization and eventually, intensification. 

It's reflected on the guidance consistently. Each operational model has a strong system nearing the Antilles.

 

 

With a strong ridge over the Atlantic, the Antilles have to watch very closely, including Puerto Rico. Once this gets to the Antilles, as you can see above there is a lot of guidance that tries to round this around the ridge. All bets are off then, as we turn our attention toward the East Coast steering pattern relative to the Atlantic ridge. 

Climo always favors OTS at this stage, but given the presence of strong ridging showing up on the guidance, this may be one that we're watching for a while, especially as guidance tends to underplay the strength of ridging. This is also where we need to watch the orientation of troughing in the eastern US, but that'll be at least 7-10 days away. 

At the very least, this is likely to be a threat to the Antilles and a significant ACE producer. 

In my estimation, 95L has the best chance to be the strongest TC in the basin this season. 

 

 

13 minutes ago, WinterWolf said:

Out to sea is always favored…the odds are always very high of that happening. 
 

Don, what makes you sure this turns into a big dog?   Is it the modeling that gives you that confidence? Or are you seeing something else? 

 

[Torch Tiger]

12 minutes ago, Damage In Tolland said:

Here she comes! 

and there she goes, way way OTS

[WinterWolf]

21 minutes ago, WxWatcher007 said:

 

 

Ahh ok…thank you for the explanation.  Didn’t read above before I posted, so missed your reasoning, my mistake. Makes sense. 
 

Edit: I went back to look for your post with the explanation Don, which said you posted it an hour ago, and I couldn’t find it?  Was it from the tropics page perhaps? 

[WxWatcher007]

29 minutes ago, WinterWolf said:

Ahh ok…thank you for the explanation.  Didn’t read above before I posted, so missed your reasoning, my mistake. Makes sense. 
 

Edit: I went back to look for your post with the explanation Don, which said you posted it an hour ago, and I couldn’t find it?  Was it from the tropics page perhaps? 

Yeah I started the thread on the invest on the main tropics page. 

[Typhoon Tip]

What we want to see is a switch in the sign of the angular momentum fields, from positive to negative...  (everyone's lost!  muah hahahaha) as the TC is approaching PR

Essentially ... the positive aspect keeps the TC chugging west across the MDR, because the STR is stronger to the N (in theory ...) with less perforated troughs enticing early polarward motion.  Also keeping shearing kinematics low. ...Then, the AAM up and decides to flip negative, which bottoms the flow out over Tennesse-ish, while there is at least a transient -NAO or even tendency there in, over the western limb of the N. Atl domain.   That former provides a 'weakness' that pulls the system parabolically NW toward the EC, and thereafter, between it and the ridge/tendency NE,  a steering conduit between also is an accelerating wind as you move N in latitude.   

That's the idealized super structure. There's probably wiggle room, but as long some 70 ... 80+% of that total relay of players are on the stage, you can say you have a good set up.   Cyclones can hit the key slot - or has a chance to ... - and moving quickly by the time it's crossing over the shelf waters S of LI, the rest can be history.

 

[Damage In Tolland]

Here we go!

[FXWX]

2 hours ago, Damage In Tolland said:

Here we go!

There's a lot of work to be done before I would be mildly interested in this setup producing any New English issue.  Believe it or not, our significant hits actually have a pretty solid footprint for trouble in place by day 10.  This one, in my opinion, does not.  Still time to change but I'm not a fan of the large-scale layout at this time.

[Diggiebot]

8 minutes ago, FXWX said:

There's a lot of work to be done before I would be mildly interested in this setup producing any New English issue.  Believe it or not, our significant hits actually have a pretty solid footprint for trouble in place by day 10.  This one, in my opinion, does not.  Still time to change but I'm not a fan of the large-scale layout at this time.

I think any New England hurricane will be sneaky. The large scale setup never looks good for a NE hurricane let’s be real. If we get one it will just happen and shock everyone not on this forum. 

[FXWX]

41 minutes ago, Diggiebot said:

I think any New England hurricane will be sneaky. The large scale setup never looks good for a NE hurricane let’s be real. If we get one it will just happen and shock everyone not on this forum. 

All righty then... it's settled.  New England gets hit by a sneaky hurricane that no one saw coming... your second sentence could not be any more inaccurate...

[STILL N OF PIKE]

1 hour ago, FXWX said:

There's a lot of work to be done before I would be mildly interested in this setup producing any New English issue.  Believe it or not, our significant hits actually have a pretty solid footprint for trouble in place by day 10.  This one, in my opinion, does not.  Still time to change but I'm not a fan of the large-scale layout at this time.

Urinating on weenie dreams with actual weather pattern discussion

[WinterWolf]

Ya it’s always a one in a million up here…and we’ll still be counting another miss two weeks from now.  Great place to live …very little atmospheric damage up this way. 

[Diggiebot]

7 hours ago, FXWX said:

There's a lot of work to be done before I would be mildly interested in this setup producing any New English issue.  Believe it or not, our significant hits actually have a pretty solid footprint for trouble in place by day 10.  This one, in my opinion, does not.  Still time to change but I'm not a fan of the large-scale layout at this time.

I think this setup looks better than most but it’s still a reach. Most likely a recurve. 

[Diggiebot]

I remember Matt noyes doing an analysis of all the points a NE hurricane passed through and this storm is hitting them all. 

[Torch Tiger]

better chance of a cold, snowy winter than that hurricane hitting us.  IOW ain't happening

[MJO812]

I doubt the next storm in the Atlantic has a chance to reach the coast .

 

It's trough season 

[Typhoon Tip]

Sandy was 'hinted' 2 weeks in advance 

Gloria 1985 modeling, though more primitive to ^, was placing players in position around the 7 day long range guidance.

Oh, what I would give to have today's technology in place on or around September 12 1938.

There's a bit of 'probability art' .  What is meant by that philosophy, you create an initial day 10 probability that is relative to perhaps 3 main factors:

seasonal pattern trend (is that favorable?);

the general state of the MDR cyclone parameters;

model performs in that time window - which believe it or not, you can have times when a day 10 chart isn't entirely without use.  

Each of those have complex positive and negative argument points (typically), and this season is no different. 

The season pattern trend, having that consummate ridge west trough east, was above average ... might be good on paper for the EC risk assessing, but it's not IF that pattern represents a -AAM hemisphere - which it did.  The MDR flow structure hasn't been very favorable for long tracks that don't succumb to early polarward turns.  HOWEVER, just this recent few days and throughout this upcoming week, the AAM has/is shifting phase - albeit likely temporary. The models are responding in kind to their own thinking with that structure, because they are bringing TC all the way across.  Not sure we can disconnect that behavior from the +AAM.. 

The general state of the MDR parametric layout is good..  SAL is minimal.  Shear in a +AAM tends to be mitigated. Ample OHC. I also like the fact that Invest 95L is situated along the 10 and not 20 during these early chapters of it's life story - whatever that turns out to be, this gives it a little wiggle roam for the unavoidable beta displacement that will take place once it gets its act together.  Said motion would bring it farther N where it can then be/risk picked up and turned, should the longitude nature of the flow start to break down earlier. All and all, this is likely the best category it's got going for it - for now.

Model performance has that relativity aspect.  The initial approach to this should be that guidance beyond day 7 is intrinsically less reliable. However, as those events in history have shown, there are those rare circumstances whence longer term performance average has a relative work-ability.  In this situation regarding 95L, I suggest the basin in time, is split.  The next 96 to 120 hour have above normal dependability, ... because the behavior proposed by guidance fits the super synoptic aspects associated with +AMM hemispheric state ('super' meaning the more abstract/emergent tendencies.  Longitudinal flow types tend to favor longitudinal results... ).   However, there is pattern delta just beyond that range removes that reliance ... falling like sailing a ship off the edge of the world. It has to do with the reintroduction of more curved flow types - models are highly susceptible to run-to-run variance - almost no reliance.

*I actually like the idea that we get a week of +AAM hemisphere followed by -AAM. The former delivers the TC west, the latter induces the turn (enthusiasts hope) in the right timing. The specifics of when/where/how/after that all happens?  That's where the dice really roll.    

 

[cleetussnow]

1 hour ago, Typhoon Tip said:

Sandy was 'hinted' 2 weeks in advance 

Gloria 1985 modeling, though more primitive to ^, was placing players in position around the 7 day long range guidance.

Oh, what I would give to have today's technology in place on or around September 12 1938.

There's a bit of 'probability art' .  What is meant by that philosophy, you create an initial day 10 probability that is relative to perhaps 3 main factors:

seasonal pattern trend (is that favorable?);

the general state of the MDR cyclone parameters;

model performs in that time window - which believe it or not, you can have times when a day 10 chart isn't entirely without use.  

Each of those have complex positive and negative argument points (typically), and this season is no different. 

The season pattern trend, having that consummate ridge west trough east, was above average ... might be good on paper for the EC risk assessing, but it's not IF that pattern represents a -AAM hemisphere - which it did.  The MDR flow structure hasn't been very favorable for long tracks that don't succumb to early polarward turns.  HOWEVER, just this recent few days and throughout this upcoming week, the AAM has/is shifting phase - albeit likely temporary. The models are responding in kind to their own thinking with that structure, because they are bringing TC all the way across.  Not sure we can disconnect that behavior from the +AAM.. 

The general state of the MDR parametric layout is good..  SAL is minimal.  Shear in a +AAM tends to be mitigated. Ample OHC. I also like the fact that Invest 95L is situated along the 10 and not 20 during these early chapters of it's life story - whatever that turns out to be, this gives it a little wiggle roam for the unavoidable beta displacement that will take place once it gets its act together.  Said motion would bring it farther N where it can then be/risk picked up and turned, should the longitude nature of the flow start to break down earlier. All and all, this is likely the best category it's got going for it - for now.

Model performance has that relativity aspect.  The initial approach to this should be that guidance beyond day 7 is intrinsically less reliable. However, as those events in history have shown, there are those rare circumstances whence longer term performance average has a relative work-ability.  In this situation regarding 95L, I suggest the basin in time, is split.  The next 96 to 120 hour have above normal dependability, ... because the behavior proposed by guidance fits the super synoptic aspects associated with +AMM hemispheric state ('super' meaning the more abstract/emergent tendencies.  Longitudinal flow types tend to favor longitudinal results... ).   However, there is pattern delta just beyond that range removes that reliance ... falling like sailing a ship off the edge of the world. It has to do with the reintroduction of more curved flow types - models are highly susceptible to run-to-run variance - almost no reliance.

*I actually like the idea that we get a week of +AAM hemisphere followed by -AAM. The former delivers the TC west, the latter induces the turn (enthusiasts hope) in the right timing. The specifics of when/where/how/after that all happens?  That's where the dice really roll.    

 

Sandy was well modeled 8 days out, never mind hinted at!  

[ineedsnow]

20/60 is a Benchmark for New Engalnd hurricanes if I remember correctly 

[MJO812]

5 minutes ago, cleetussnow said:

Sandy was well modeled 8 days out, never mind hinted at!  

That was when the Euro was great 

[ineedsnow]

[Typhoon Tip]

22 minutes ago, cleetussnow said:

Sandy was well modeled 8 days out, never mind hinted at!  

Yeah, and the word 'hinted' was a conservative usage, too. 

I'd say by day 12 lead even it seemed all the major players were unavoidably going to be put into position. This was both modeled to be so, ...but the trend/abstractions ( the 'super synopsis' aspects), gave the allusion to the event.  Thus, combining the more rational/materialized solution set ( modeling... extended or not!) with that... 

... the thing about probability chi-test shit, it's maybe something to do with the 'chi-square test' - which is among the 'non-parametric test' ... The definition of those where they don’t make as many assumptions about the data. The common statistical assumptions can be violated...  Sounds like something useful in the present context...

But whatever, Sandy was just going to happen.  It was a matter of ironing out details

[WinterWolf]

3 hours ago, Torch Tiger said:

better chance of a cold, snowy winter than that hurricane hitting us.  IOW ain't happening

Why do you give me a weenie, when I said something similar in regard to this TC? We all know the odds are always very low of a TC strike up here…and when others/me say that, you throw a weenie?  Makes no sense? 

[FXWX]

7 hours ago, Diggiebot said:

I remember Matt noyes doing an analysis of all the points a NE hurricane passed through and this storm is hitting them all. 

You can hit all the benchmarks you want, if the door Infront of the system is not open it doesn't matter.  Go back and look at the 500 mb before all of our previous hits!!!  When they were going through the check points the pattern ahead of them was already evolving in a threatening way... 

[kdxken]

46 minutes ago, WinterWolf said:

Why do you give me a weenie, when I said something similar in regard to this TC? We all know the odds are always very low of a TC strike up here…and when others/me say that, you throw a weenie?  Makes no sense? 

He has a thing about weenies.

[Typhoon Tip]

1 hour ago, FXWX said:

You can hit all the benchmarks you want, if the door Infront of the system is not open it doesn't matter.  Go back and look at the 500 mb before all of our previous hits!!!  When they were going through the check points the pattern ahead of them was already evolving in a threatening way... 

Yeah ...my write up above may have been a bit too long for the attention .. but 95L has this (bold).  The probabilities for this system seems to seesawed quite a bit, with these first 4 or 5 days at higher than normal confidence, and then abruptly dropping to no confidence beyond. 

There's two domain spaces ( obviously...).  The tropics.  Then, outside the tropics.   When a system is in the tropics, there's a predictive "event horizon" so to speak..  Can't see over the boundary, which occurs along the track where accurate spatial and spatial temporal timing (both) of westerly mechanics begin to interact.  

The jet is active around 50 N across the continent, ...modeled to be that way from ~ day 5 or 6, out to the end of the run.  However, the models are positioning waves from S of Alaska to the N Atlantic, with poor continuity.  So long as that remains so, there's virtually no way to assess how a 95L's future will interact with the westerlies.  

Just in general audience ... for every system that long tracked and ended up 60 naut mil N of PR through the key slot, ultimately to make a destiny with an EC landfall, there have been 99 that curved harmless out to sea - figuratively speaking - or turned back W and smacked Florida.  

[Torch Tiger]

2 hours ago, WinterWolf said:

Why do you give me a weenie, when I said something similar in regard to this TC? We all know the odds are always very low of a TC strike up here…and when others/me say that, you throw a weenie?  Makes no sense? 

Yes of course it's low odds, but you said there have been no major hurricane strikes since 1938 which is false.

[WinterWolf]

2 hours ago, Torch Tiger said:

Yes of course it's low odds, but you said there have been no major hurricane strikes since 1938 which is false.

What “major” hurricane hit us in SNE since ‘38?   Major being Category 3 and up? Gloria and Bob weren’t even close to majors when they hit us.  And Carol and Diane and the others in the 50’s I don’t believe were majors when they hit up here either. Sandy wasn’t even classified as tropical, and hit in Jersey.  But enlighten me if any were Cat 3’s when hitting us, because maybe I’m wrong as you claim? 

[Damage In Tolland]

Definitely this is one to keep a close eye on. Some pieces are starting to come together slowly 

[WinterWolf]

Just now, Damage In Tolland said:

Definitely this is one to keep a close eye on. Some pieces are starting to come together slowly 

Still far enough out there that things can’t be ruled out, but we need to see the door opening as FXWX said.