2021 Global Model Runs Discussion (Out thru day 16)

[LarryWx]

12Z GFS is the 5th run in a row taking this same 9/10-11 emerging AEW into the Caribbean ~9/18 as a result of it staying weak. This wave is what is causing the convection at the Lesser Antilles on the far right in this image:

[LarryWx]

3 potential systems on the Canadian.

https://i.imgur.com/Ujj3015.png

The one in this 12Z CMC at 17N, 44W, is the same 9/11 AEW and is much stronger and further out I think than on any other CMC run. It is moving almost due west then.

[jlauderdal]

3 potential systems on the Canadian.

The canadian is the new gfs

[toad strangler]

3 potential systems on the Canadian.

https://i.imgur.com/Ujj3015.png

The canadian is the new gfs

Nah. that's a parade of just AEW's. Entirely plausible.

[aspen]

3 potential systems on the Canadian.

https://i.imgur.com/Ujj3015.png

The canadian is the new gfs

Nah. that's a parade of just AEW's. Entirely plausible.

A parade of AEWs that could develop into 1-3 named storms. The westernmost wave would be in the high OHC, 29-30C SST waters north of the Greater Antilles and in the Bahamas, while the easternmost wave seems to come off at a low latitude and could get decently far west.

[LarryWx]

12Z GFS is the 5th run in a row taking this same 9/10-11 emerging AEW into the Caribbean ~9/18 as a result of it staying weak. This wave is what is causing the convection at the Lesser Antilles on the far right in this image:

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

Just like the prior run, the 12Z Euro has a sharp far E Atlantic recurve though not as early as the 0Z, which went quickly back into Africa.
This is still evolving as the Euro had it come off Africa way up at 20N a few days ago. Now it is down to 16N and that's still 5 days out. So, far from set in stone yet. It may still recurve sharply, but if it stays weak near Africa, it likely wouldn't sharply recurve.

[CyclonicFury]

The wave exiting Africa around September 11 may be one to watch for development. As usual, the ECMWF likely develops it too quickly (inland over Africa as part of a model bias), but this could develop pretty close to the Cabo Verde Islands. It will have peak season climo favoring it. Could be something similar to Rene last year.

[LarryWx]

 And for the first time now we have a substantial split on the 12Z EPS, the sharp recurvers and those left behind moving mainly westward just past 30W, which means lots of uncertainty/this is still evolving:

[LarryWx]

12Z EPS end of run: None of these below 30N are from the wave moving off ~9/11 and instead are from followups:

[AlphaToOmega]

The GEFS and ECENS ensembles show development of Invest 91L, another Gulf of Mexico storm, and another Cape Verde storm all within the next few days. I think it is time for people in the tropics to be alert about these systems.

[Clearcloudz]

The GEFS and ECENS ensembles show development of Invest 91L, another Gulf of Mexico storm, and another Cape Verde storm all within the next few days. I think it is time for people in the tropics to be alert about these systems.

A lot of sinking air in the Atlantic going on right now while larry is avoiding it. Everything else seems to have a lid on it at the moment. However something to watch going into next week is were heading into MJO phase 3 which lines with climo peak.

[SFLcane]

12Z EPS end of run: None of these below 30N are from the wave moving off ~9/11 and instead are from followups:

https://i.imgur.com/yZ2MAwt.png

An uptick in week 3 continues to look likely. Most of those lows in the long range EPS appear to be heading NW and out to sea.

[aspen]

I’m not buying the Euro’s solution of the 9/10 wave emerging at like 20N and going due north the minute it hits open water.

[SFLcane]

In terms of steering the CMC, EPS, GEFS and CFSv2 and IMME all support the developments of blocking in the Atlantic. For now it’s best not to jump on any particular solution at this point but it definitely garners attention since we are in peak climo season.

[SFLcane]

I have found that models have a tough time handling the time period immediately after a significant hurricane, especially in the open ocean, especially with upwelling and such. My guess is that once Larry clears, the playing field will reset and we'll get a better understanding of what's to come.

[IcyTundra]

The Euro has a known bias to shoot out tropical waves coming off of Africa at too high of a latitude. Looking at the NOAA Historical Hurricane Tracks site there have been very few storms that have formed that came off of Africa that far north.

[Category5Kaiju]

I’m not buying the Euro’s solution of the 9/10 wave emerging at like 20N and going due north the minute it hits open water.

Maybe it’s a TD10 redux ? Idk, although it’s the time of year when TSs can be named very close to the Cape Verde islands

[AlphaToOmega]

That soon-to-be tropical wave deserves to be mentioned in the next TWO.

[IcyTundra]

I expect two new areas of interest to be added to the TWO in the coming days. The AEW emerging on 9/11 probably has higher odds of developing than the area in the W Carribean but both should be watched closely.

[Category5Kaiju]

Ok, so the most recent GFS run has only Olaf develop in the EPAC with the EPAC and Atlantic quiet with no discernable, sustained cyclone developing afterwards until the 22nd of September. That's just weird to say the least.