Tropical Wave in Central Atlantic (Is Invest 91L)

[Iceresistance]

I really hope that this is not Ian 2.0, Ian's origin also came from a TW from Africa and was a sleeper wave until it reached the Caribbean. Except that this time, there is no Outflow shear from Fiona.

Wind shear is very low in the Eastern Caribbean
Little to no dry air or SAL
No Cold Water Trail from Ian, OHC (Ocean Heat Content) is still very high.

We could have another monster hurricane in the Caribbean from this system. But where it will go? That is anyone's question right now.

[Category5Kaiju]

Just...watch this steal Julia from the far Eastern AOI

[SFLcane]

 https://twitter.com/bryannorcrosstv/status/1576563688835891203

[SFLcane]

 https://twitter.com/yconsor/status/1576566149986541572

[SFLcane]

I really hope that this is not Ian 2.0, Ian's origin also came from a TW from Africa and was a sleeper wave until it reached the Caribbean. Except that this time, there is no Outflow shear from Fiona.

Wind shear is very low in the Eastern Caribbean
Little to no dry air or SAL
No Cold Water Trail from Ian, OHC (Ocean Heat Content) is still very high.

We could have another monster hurricane in the Caribbean from this system. But where it will go? That is anyone's question right now.

It’s still very early but as of right now there is 0 indication this will be the case. Ensembles for now keep a strong ridge in place and drive it west into CA. The Caribbean might be active but the hope is Ian was it for the Conus.

[cycloneye]

 https://twitter.com/yconsor/status/1576567072573693952

[ColdMiser123]

https://twitter.com/yconsor/status/1576566149986541572?s=46&t=eZqcy-naF5bOl1H9ewfd7g

This is a great point and visualization of the GEFS ridge bias compared to the GEPS/EPS. Likely that this does go south of the US into central America, given the ridge in place.

However, I wouldn't rule out a track farther north, the trend has been to slow down the trough associated with the remnants of Ian to bring it farther southwest at a given forecast stamp, and as a result, we have been progressively trending toward weaker ridging in the west Caribbean. Something to watch.

[kevin]

These are not the type of AOIs you want to see this time of year. October storms entering the WCar have a tendency to blow up into big ones. If we get a hurricane this season stronger than Fiona or Ian this is the region where it will happen. And no matter where it makes landfall, pretty much the entirety of CA coast is quite densely populated and we've seen what kind of damage + loss of life that can cause (Eta and Iota recently). So my hurricane heart is excited for another potential storm to track, but on the other hand I also hope it won't become as big as some of those GEFS members are showing. Guess I can't change it either way so best just to sit and wait.

[ColdMiser123]

That trend also appears to be in place across the west Caribbean due to ensembles picking up on a stronger than forecast Orlene across the east Pacific as well.

[jconsor]

Great point here ColdMiser! Can you elaborate on how you feel a stronger than forecast Orlene in the E. Pacific would influence the upper pattern in the W. Atlantic/Caribbean and potential for a further north track?

https://twitter.com/yconsor/status/1576566149986541572?s=46&t=eZqcy-naF5bOl1H9ewfd7g

This is a great point and visualization of the GEFS ridge bias compared to the GEPS/EPS. Likely that this does go south of the US into central America, given the ridge in place.

However, I wouldn't rule out a track farther north, the trend has been to slow down the trough associated with the remnants of Ian to bring it farther southwest at a given forecast stamp, and as a result, we have been progressively trending toward weaker ridging in the west Caribbean. Something to watch.

https://i.imgur.com/GfT9Kn8.gif

[jconsor]

Thanks for posting this, cycloneye! Below is the entire Twitter thread for full context.

Quick summary:
I'd recommend being wary of GEFS members showing a potential path northward for the system entering the Caribbean middle of this week. 

IMHO, *if* it fails to become a TS with a well-defined circulation before the latitude of the Dominican Republic (~70W), it looks most likely to be a straight W/WNW tracker like the Tampico Hurricane in 1933, Janet in 1954, Joan in 1988 and Iris in 2001, heading into Central America or southern Mexico.  However, if it manages to develop sooner, especially on approach to the Windward Islands, the picture becomes much more complicated.

 https://twitter.com/yconsor/status/1576561961671614464




 https://twitter.com/yconsor/status/1576567072573693952




 https://twitter.com/yconsor/status/1576569989946933248




 https://twitter.com/yconsor/status/1576573038429995008

https://twitter.com/yconsor/status/1576567072573693952

[Category5Kaiju]

Also something to keep in mind, but the theme of this year, especially since at least early September, has strongly favored troughing. Hence all but one of our hurricanes so far, Earl, Fiona, and Ian, recurved at some point in their lives instead of getting shoved westward throughout.

[ColdMiser123]

Great point here ColdMiser! Can you elaborate on how you feel a stronger than forecast Orlene in the E. Pacific would influence the upper pattern in the W. Atlantic/Caribbean and potential for a further north track?

https://twitter.com/yconsor/status/1576566149986541572?s=46&t=eZqcy-naF5bOl1H9ewfd7g

This is a great point and visualization of the GEFS ridge bias compared to the GEPS/EPS. Likely that this does go south of the US into central America, given the ridge in place.

However, I wouldn't rule out a track farther north, the trend has been to slow down the trough associated with the remnants of Ian to bring it farther southwest at a given forecast stamp, and as a result, we have been progressively trending toward weaker ridging in the west Caribbean. Something to watch.

https://i.imgur.com/GfT9Kn8.gif

The mountains of Mexico should take care of the vast majority of Orlene's vorticity, however a stronger Orlene initially could lead to there being more being left over in the Gulf later on, lowering heights overall in that region, not entirely sure if the Euro is fully capturing this effect or not, since the 6z run initialized it as a 1002 mb low.

Which also goes to the point you were making about the steering flow potentially becoming complicated if the wave becomes stronger earlier on.

[ScottNAtlanta]

Looking at N Atlantic winds and analysis at U Wis. it looks like the shear it is under isn't going to get any worse than now as it diminishes west. It also has a vorticity signature 500mb all the way down. While rather weak at the surface, it is still there. There is also lots of diffluent upper air flow which is helping thunderstorms form, as well as lower level convergence. This looks a lot healthier than most of the waves in this area this season as far as dry air goes.

[ColdMiser123]

The GFS did a reasonable job with Orlene's intensity with its approach into Mexico, and it has a resulting stronger shortwave trough over Texas, which contributes to the weaker ridging over the GOM/west Caribbean relative to the Euro in the short term.

[cheezyWXguy]

Is today my birthday? So much pro-met content in this thread, and we’re only on page two. Really appreciate the insight you guys are providing. The posts here, pro and otherwise, are what I come to s2k for

[pcolaman]

Had a question, I have a cruise planned for the 17 the out of N.O. We are heading to Cozumel and Yucatan Progresso that week. How do we stand as far as tropical development the week of the 17th. ? You think our trip might be in trouble?

[gatorcane]

Curious what the 12Z guidance does given the enhanced convection we are seeing. Based on this guidance, we might see an invest tag today.

[South Texas Storms]

Had a question, I have a cruise planned for the 17 the out of N.O. We are heading to Cozumel and Yucatan Progresso that week. How do we stand as far as tropical development the week of the 17th. ? You think our trip might be in trouble?

Too early to have any confidence in the forecast that far out. I do think that the northwest Gulf is likely done with tropical threats for the year. The Caribbean and the eastern Gulf looks to remain under an elevated threat over the next few weeks though.

I think this system will likely remain in the Caribbean and make an eventual landfall over Central America in a little over a week. Can't rule out a track farther north into the Gulf. But right now, that risk looks low.

[mantis83]

Had a question, I have a cruise planned for the 17 the out of N.O. We are heading to Cozumel and Yucatan Progresso that week. How do we stand as far as tropical development the week of the 17th. ? You think our trip might be in trouble?

Too early to have any confidence in the forecast that far out. I do think that the northwest Gulf is likely done with tropical threats for the year. The Caribbean and the eastern Gulf looks to remain under an elevated threat over the next few weeks though.

I think this system will likely remain in the Caribbean and make an eventual landfall over Central America in a little over a week. Can't rule out a track farther north into the Gulf. But right now, that risk looks low.

agreed