Central Atlantic Tropical Wave (Is Invest 91L)

[LarryWx]

The wave that leads to the numerous EPS members on the last 3 runs threatening mainly the Bahamas, the SE/E/Gulf coasts of the US, and Bermuda during the mid to late portions of the first week of Sept. is the prominent one now over Africa near 0 longitude between 10N and 20N. It is forecasted to emerge from Africa on Thursday, 8/27. This is quite robust and already shows curvature. When considering that along with what appear to be generally favorable atmospheric conditions as well as warm SSTs ahead in the MDR and with it being in the heart of the active season during La Nina when many historic storms originated, this one is liable to be a long tracking beast that would be followed for 2 weeks+. We'll see:

[SFLcane]

The wave that leads to the numerous EPS members on the last 3 runs threatening mainly the Bahamas, the SE/E/Gulf coasts of the US, and Bermuda during the mid to late portions of the first week of Sept. is the prominent one now over Africa near 0 longitude between 10N and 20N. It is forecasted to emerge from Africa on Thursday, 8/27. This is quite robust and already shows curvature. When considering that along with what appear to be generally favorable atmospheric conditions as well as warm SSTs ahead in the MDR and with it being in the heart of the active season during La Nina when many historic storms originated, this one is liable to be a long tracking beast that would be followed for 2 weeks+. We'll see:


http://tropic.ssec.wisc.edu/real-time/europe/images/irnm7.GIF

Could be highlighted in the TWO during the next couple of days.

[CyclonicFury]

The ECMWF has suggested this wave will likely be broad and exit Africa at a high latitude, so immediate development may not occur. This wave likely won't start to organize until it is west of 50°W.

The FV3 GFS seems nearly unable to develop tropical waves significantly over the MDR in the long range, so it is not a surprised there is a lack of GFS signal yet.

[sma10]

We'll see how things turn out, but I notice that many of the ensembles depict not only a strong storm, but also a very large one

[LarryWx]

The 18Z GFS has a "landfall" of the African wave being followed here as a weak low near Jacksonville, FL, just after hour 306 on Sept 6 moving westward, which then was followed by more westward movement to the Gulf coast as an even weaker feature that then meets up with a cold front near the MS River on Sep 8. The point of this is to show that westerly steering may be dominating then due to ridging to the north:



Edit: The 18Z GEFS has essentially nothing.

[chaser1]

Larry alluded to several Euro members suggesting an eventual threat to the Bahamas or SE Conus. Well as of this afternoon, the EURO continues to bring Nana closer to the Leeward Islands AND now has additional support from the GEM and ICON as well. I'm fairly confident that this will be La Nana unless some other quick spin-up grabs the name first.

[Hurricaneman]

The fact that the GFS shows a broad low near Jacksonville from this is cause for concern as every other model develops this and a broad low on the GFS could equal hurricane

[SFLcane]

Here it comes! Impressive spin

 https://twitter.com/stuostro/status/1298045381486551040

[SFLcane]

18z EPS develops this upcoming weekend if not sooner.

[WeatherEmperor]

Here is the latest 0z ICON. I am not sure which of the 2 is the wave discussed in this thread




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[sma10]

Here is the latest 0z ICON. I am not sure which of the 2 is the wave discussed in this thread

https://uploads.tapatalk-cdn.com/20200825/b43809565a0b209566481d572ec2f662.jpg


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It's the lead one. Haven't seen trailing development so close behind, might be spurious... We'll see

[WeatherEmperor]

The Canadian has it entering the picture around 7 days and moves it at a slow pace WNW through 10 days





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[cycloneye]

ECMWF is more weaker and more south.

[SFLcane]

 https://twitter.com/andyhazelton/status/1298205809038499840

[SFLcane]

ECMWF is more weaker and more south.

https://i.imgur.com/YOKMWp8.gif

Isaias v2.0

[SFLcane]

Here is the latest 0z ICON. I am not sure which of the 2 is the wave discussed in this thread

https://uploads.tapatalk-cdn.com/20200825/b43809565a0b209566481d572ec2f662.jpg


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Almost a double barreled wave like Isaias.

[SFLcane]

The gfs for now just pure speculation is showing a trof preventing the subtropical ridge from forming to strong. Also this wave is coming off at a fairly high latitude which “ may “ imply a recurve into the open Atlantic sooner rather then later.

We shall see it has to develop first

[AutoPenalti]

The gfs for now just pure speculation is showing a trof preventing the subtropical ridge from forming to strong. Also this wave is coming off at a fairly high latitude which “ may “ imply a recurve into the open Atlantic sooner rather then later.

We shall see it has to develop first

https://i.imgur.com/VzI27Mp.png

Same trough that GFS had developing when Laura was in the MDR? and then disappeared when it got closer to the GA’s?

[SFLcane]

The gfs for now just pure speculation is showing a trof preventing the subtropical ridge from forming to strong. Also this wave is coming off at a fairly high latitude which “ may “ imply a recurve into the open Atlantic sooner rather then later.

We shall see it has to develop first

https://i.imgur.com/VzI27Mp.png

Same trough that GFS had developing when Laura was in the MDR? and then disappeared when it got closer to the GA’s?

Yep, lol. climatologically the ridge weakens in September so we shall see.

[toad strangler]

Euro shows a trough as well, albeit a little bit later than 192