ATL: TEDDY - Post-Tropical - Discussion

[Spacecoast]

Invest 95L
Current position: 10.7N, 20W
in ~114hrs (12z Tuesday), the GFS has it located @12.52N, 51.8W, traveling 2153 statute miles (assuming straight line)
on 12z Tuesday, Euro has it located @ 14.51N, 41.12W, traveling only 1513 statute miles

According to my calculations, the GFS has it averaging 18.9 mph,vs. the Euro averaging only 13.27mph.

Isn't >18.9 mph rather fast for a hurricane?
What is the typical forward speed for this journey?

[StPeteMike]

Getting Irma feels with these early model runs..

[CrazyC83]

This was a record for Talking Tropics forum but here we are. Now let's see how many pages this thread and the models thread will have.

Something tells me this thread will be a long one and this system will be one that we really have to pay attention to.

[sma10]

Invest 95L
Current position: 10.7N, 20W
in ~114hrs (12z Tuesday), the GFS has it located @12.52N, 51.8W, traveling 2153 statute miles (assuming straight line)
on 12z Tuesday, Euro has it located @ 14.51N, 41.12W, traveling only 1513 statute miles

According to my calculations, the GFS has it averaging 18.9 mph,vs. the Euro averaging only 13.27mph.

Isn't >18.9 mph rather fast for a hurricane?
What is the typical forward speed for this journey?

A due west motion of 15-16 knots is a little quick, but not totally unusual for the eastern/central atlantic

[Blown Away]

Invest 95L
Current position: 10.7N, 20W
in ~114hrs (12z Tuesday), the GFS has it located @12.52N, 51.8W, traveling 2153 statute miles (assuming straight line)
on 12z Tuesday, Euro has it located @ 14.51N, 41.12W, traveling only 1513 statute miles

According to my calculations, the GFS has it averaging 18.9 mph,vs. the Euro averaging only 13.27mph.

Isn't >18.9 mph rather fast for a hurricane?
What is the typical forward speed for this journey?

Common for a TW in the E to Central Atlantic to move @20 mph if it’s in the low level easterlies...

[Cat5James]

Western lobe appears dominant at the moment

[HuracanMaster]

For those who watched Levi's video, the two biggest takeaways I saw was:

1. The potential for Rene to bounce around up and down between ridges in the open Atlantic and mess with a slower more consolidated 95L and draw it N. (12z Euro)
2. The western lobe of 95L fast tracking to the W away from the E lobe and getting underneath a building ridge that would send it towards the Caribbean regardless of Rene's antics. 12z GFS

That's what to watch for first.

From what I see faster movement to the west is already ocurring so GFS may be onto something here [img][img][/img][/img] so, yes serve me # 2 with a side of fries please!

[USTropics]

According to Levi it will go further west if the western lobe detaches or separates quicker (which it already seems to be doing), which would get it west enough to get caught under a ridge and shove it towards the Caribbean. If for some reason it gets tangled up and remains near the other lobe it will be far enough east to be pulled north by a weakness in the ridge by an ULL and Rene that is going to be entangled with it. So far, the GFS seems to be correct. I suppose USTropics could describe it better then I can if he wants

All in all it reminds me of Isaac from 2018 which had a similar setup (ridge NW of it + Florence being north of it and if it was going to move fast enough to get caught under which it did which models also disagreed on).

You pretty much nailed it. This is the process that has been occurring/will continue for the next 24 hours or so. This image is from ~8 hours ago, when we started to see a distinction in the northern and southern wave axis of 95L (highlighted in orange and tilted NW to SE). The northern lobe of vorticity will fracture (blue) and will continue to push towards the WSW. This is being aided by a large, leading moisture surge pushing in from the east associated with the wave axis behind 95L (purple). The southern lob/wave axis (red) should slowly be drawn NW, and as Levi illustrated how close this interacts with the northern lobe will be critical in how far west it can get in the next 24-48 hours. I've included an animation below of this process as well.





In about 60 hours how far west this gets becomes critical. We're talking literally a couple hundred miles will be the difference. To illustrate this, here is the 18z GFS position (which has consistently brought this west), the 00z ECMWF position (which brought this west), and the 12z ECMWF position (which quickly moves this north over the CATL), all for 00z on September 13th. You'll notice it's largely a matter of a few hundred miles that makes the difference of this getting completely under the ridge or not:

[Aric Dunn]

According to Levi it will go further west if the western lobe detaches or separates quicker (which it already seems to be doing), which would get it west enough to get caught under a ridge and shove it towards the Caribbean. If for some reason it gets tangled up and remains near the other lobe it will be far enough east to be pulled north by a weakness in the ridge by an ULL and Rene that is going to be entangled with it. So far, the GFS seems to be correct. I suppose USTropics could describe it better then I can if he wants

All in all it reminds me of Isaac from 2018 which had a similar setup (ridge NW of it + Florence being north of it and if it was going to move fast enough to get caught under which it did which models also disagreed on).

You pretty much nailed it. This is the process that has been occurring/will continue for the next 24 hours or so. This image is from ~8 hours ago, when we started to see a distinction in the northern and southern wave axis of 95L (highlighted in orange and tilted NW to SE). The northern lobe of vorticity will fracture (blue) and will continue to push towards the WSW. This is being aided by a large, leading moisture surge pushing in from the east associated with the wave axis behind 95L (purple). The southern lob/wave axis (red) should slowly be drawn NW, and as Levi illustrated how close this interacts with the northern lobe will be critical in how far west it can get in the next 24-48 hours. I've included an animation below of this process as well.

https://i.imgur.com/23tqWD6.png

https://i.ibb.co/7N8mj2w/45184123.gif

In about 60 hours how far west this gets becomes critical. We're talking literally a couple hundred miles will be the difference. To illustrate this, here is the 18z GFS position (which has consistently brought this west), the 00z ECMWF position (which brought this west), and the 12z ECMWF position (which quickly moves this north over the CATL), all for 00z on September 13th. You'll notice it's largely a matter of a few hundred miles that makes the difference of this getting completely under the ridge or not:

https://i.ibb.co/QvK7nx8/Webp-net-gifmaker-8.gif

just to sort of further this since we have some ASCAT...

The curvature to the western lobe and convection which has some divergent easterly shear would favors the LLC to consolidate farther west especially if the Convection maintains there and dies off with that surge coming from the east.

given the progression of the western lobe and the sustained convection... it would at the moment appear to be favoring the GFS.

[USTropics]

According to Levi it will go further west if the western lobe detaches or separates quicker (which it already seems to be doing), which would get it west enough to get caught under a ridge and shove it towards the Caribbean. If for some reason it gets tangled up and remains near the other lobe it will be far enough east to be pulled north by a weakness in the ridge by an ULL and Rene that is going to be entangled with it. So far, the GFS seems to be correct. I suppose USTropics could describe it better then I can if he wants

All in all it reminds me of Isaac from 2018 which had a similar setup (ridge NW of it + Florence being north of it and if it was going to move fast enough to get caught under which it did which models also disagreed on).

You pretty much nailed it. This is the process that has been occurring/will continue for the next 24 hours or so. This image is from ~8 hours ago, when we started to see a distinction in the northern and southern wave axis of 95L (highlighted in orange and tilted NW to SE). The northern lobe of vorticity will fracture (blue) and will continue to push towards the WSW. This is being aided by a large, leading moisture surge pushing in from the east associated with the wave axis behind 95L (purple). The southern lob/wave axis (red) should slowly be drawn NW, and as Levi illustrated how close this interacts with the northern lobe will be critical in how far west it can get in the next 24-48 hours. I've included an animation below of this process as well.

https://i.imgur.com/23tqWD6.png

https://i.ibb.co/7N8mj2w/45184123.gif

In about 60 hours how far west this gets becomes critical. We're talking literally a couple hundred miles will be the difference. To illustrate this, here is the 18z GFS position (which has consistently brought this west), the 00z ECMWF position (which brought this west), and the 12z ECMWF position (which quickly moves this north over the CATL), all for 00z on September 13th. You'll notice it's largely a matter of a few hundred miles that makes the difference of this getting completely under the ridge or not:

https://i.ibb.co/QvK7nx8/Webp-net-gifmaker-8.gif

just to sort of further this since we have some ASCAT...

The curvature to the western lobe and convection which has some divergent easterly shear would favors the LLC to consolidate farther west especially if the Convection maintains there and dies off with that surge coming from the east.

given the progression of the western lobe and the sustained convection... it would at the moment appear to be favoring the GFS.

https://i.ibb.co/x7Ntgng/Capture.png

And you can start to see the difference in the 12z ECWMF run. Here is an actual IR satellite image for 00z (about 2.5 hours ago):


Here is the 12z ECMWF high-def IR forecast for 00z:


a) its miscalculated the speed and moisture envelope to the east
b) its miscalculated the amount of convection associated with the western lobe

[Aric Dunn]

You pretty much nailed it. This is the process that has been occurring/will continue for the next 24 hours or so. This image is from ~8 hours ago, when we started to see a distinction in the northern and southern wave axis of 95L (highlighted in orange and tilted NW to SE). The northern lobe of vorticity will fracture (blue) and will continue to push towards the WSW. This is being aided by a large, leading moisture surge pushing in from the east associated with the wave axis behind 95L (purple). The southern lob/wave axis (red) should slowly be drawn NW, and as Levi illustrated how close this interacts with the northern lobe will be critical in how far west it can get in the next 24-48 hours. I've included an animation below of this process as well.

https://i.imgur.com/23tqWD6.png

https://i.ibb.co/7N8mj2w/45184123.gif

In about 60 hours how far west this gets becomes critical. We're talking literally a couple hundred miles will be the difference. To illustrate this, here is the 18z GFS position (which has consistently brought this west), the 00z ECMWF position (which brought this west), and the 12z ECMWF position (which quickly moves this north over the CATL), all for 00z on September 13th. You'll notice it's largely a matter of a few hundred miles that makes the difference of this getting completely under the ridge or not:

https://i.ibb.co/QvK7nx8/Webp-net-gifmaker-8.gif

just to sort of further this since we have some ASCAT...

The curvature to the western lobe and convection which has some divergent easterly shear would favors the LLC to consolidate farther west especially if the Convection maintains there and dies off with that surge coming from the east.

given the progression of the western lobe and the sustained convection... it would at the moment appear to be favoring the GFS.

https://i.ibb.co/x7Ntgng/Capture.png

And you can start to see the difference in the 12z ECWMF run. Here is an actual IR satellite image for 00z (about 2.5 hours ago):
https://i.imgur.com/PbRClvO.png

Here is the 12z ECMWF high-def IR forecast for 00z:
https://i.imgur.com/YDUoX7m.png

a) its miscalculated the speed and moisture envelope to the east
b) its miscalculated the amount of convection associated with the western lobe

and if you look at the Euro IR .. you can clearly see an MLC well inland over western africa. that obviously did not pan out.. and that likely led to the euro tilting the wave axis and favoring the eastern lobe.

[Hurricaneman]

Already has the look of a future major hurricane, the Lesser Antilles need to stay vigilant and hope for the best

[us89]

You pretty much nailed it. This is the process that has been occurring/will continue for the next 24 hours or so. This image is from ~8 hours ago, when we started to see a distinction in the northern and southern wave axis of 95L (highlighted in orange and tilted NW to SE). The northern lobe of vorticity will fracture (blue) and will continue to push towards the WSW. This is being aided by a large, leading moisture surge pushing in from the east associated with the wave axis behind 95L (purple). The southern lob/wave axis (red) should slowly be drawn NW, and as Levi illustrated how close this interacts with the northern lobe will be critical in how far west it can get in the next 24-48 hours. I've included an animation below of this process as well.

https://i.imgur.com/23tqWD6.png

https://i.ibb.co/7N8mj2w/45184123.gif

In about 60 hours how far west this gets becomes critical. We're talking literally a couple hundred miles will be the difference. To illustrate this, here is the 18z GFS position (which has consistently brought this west), the 00z ECMWF position (which brought this west), and the 12z ECMWF position (which quickly moves this north over the CATL), all for 00z on September 13th. You'll notice it's largely a matter of a few hundred miles that makes the difference of this getting completely under the ridge or not:

https://i.ibb.co/QvK7nx8/Webp-net-gifmaker-8.gif

just to sort of further this since we have some ASCAT...

The curvature to the western lobe and convection which has some divergent easterly shear would favors the LLC to consolidate farther west especially if the Convection maintains there and dies off with that surge coming from the east.

given the progression of the western lobe and the sustained convection... it would at the moment appear to be favoring the GFS.

https://i.ibb.co/x7Ntgng/Capture.png

And you can start to see the difference in the 12z ECWMF run. Here is an actual IR satellite image for 00z (about 2.5 hours ago):
https://i.imgur.com/PbRClvO.png

Here is the 12z ECMWF high-def IR forecast for 00z:
https://i.imgur.com/YDUoX7m.png

a) its miscalculated the speed and moisture envelope to the east
b) its miscalculated the amount of convection associated with the western lobe

It also appears to have miscalculated the strength of Paulette. A stronger Paulette probably means a weaker Rene, which likely makes an early northward turn less likely for 95L.

[Aric Dunn]

Great pass ..

This is showing almost exaclty what the GFS was has been showing the last few runs. and what has been discussed here earlier...

The Surge has forced the vorticity farther west.. it can bee seen in the latest satellite loops as well.

this opens the door for the islands to be directly impacted..

after that the window is open from South of Cuba to the SE US.



https://i.ibb.co/bbwGXdB/20200911-0259- ... W-96pc.jpg

[Aric Dunn]

Great pass ..

This is showing almost exaclty what the GFS was has been showing the last few runs. and what has been discussed here earlier...

The Surge has forced the vorticity farther west.. it can bee seen in the latest satellite loops as well.

this opens the door for the islands to be directly impacted..

after that the window is open from South of Cuba to the SE US.

https://i.ibb.co/hHdcDTp/Capture.png

https://i.ibb.co/bbwGXdB/20200911-0259- ... W-96pc.jpg

brand new one.. a couple hours newer than the last.

showing even more organization with the west lobe.



https://www.fnmoc.navy.mil/tcweb/dynami ... .045pc.jpg

[bob rulz]

Apologize if this isn't the right thread, but I thought this was noteworthy. The active tropical wave train has been wreaking havoc on the Sahel region of Africa, particularly Senegal.

https://www.cnbc.com/2020/09/10/record- ... hocks.html

This was all before this wave passed as well - you can see some really intense rainfall over Senegal as this splashes down.

[FireRat]

Apologize if this isn't the right thread, but I thought this was noteworthy. The active tropical wave train has been wreaking havoc on the Sahel region of Africa, particularly Senegal.

https://www.cnbc.com/2020/09/10/record- ... hocks.html

This was all before this wave passed as well - you can see some really intense rainfall over Senegal as this splashes down.

Jeez man, they got clobbered hard with what they are calling 'unprecedented' rainfall in the area! This goes to show just how active the wave train is and how the Cape Verde season is trying hard to get going!

Thanks for posting, it's good to know how they are doing in Africa. These waves are incredible this season, and 95L certainly added to their woes.

[us89]

Up to 70/90

3. A tropical wave is located a few hundred miles south of the Cabo
Verde Islands and is producing a large area of disorganized showers
and thunderstorms. Development of this system is forecast, and a
tropical depression is expected to form within the next few days
while the system moves generally westward at 15 to 20 mph across
the eastern and central tropical Atlantic.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

[Do_For_Love]

lol wrong thread - meant to post in the Paulette thread. I'll just say that like everyone else I'm keeping an eye on this storm and waiting to see what path it takes and how the intensity shapes up.

[cycloneye]

95L INVEST 200911 1200 11.0N 25.0W ATL 25 1008