2022 Global Model Runs Discussion (Out thru day 16)

[Cpv17]

12Z EPS very bullish, same for GEFS

https://uploads.tapatalk-cdn.com/20220821/a458fa5d0f5d80bd9a2ea3123ee70580.jpg

https://uploads.tapatalk-cdn.com/20220821/0bb12595109c6146d4db6f13b60b156f.jpg


Sent from my iPhone using Tapatalk

So basically everything that comes off Africa is OTS according to the EPS.

[sma10]

Major hurricane to strike Houston/Galveston Sept. 8th. No doubt about it, the 12Z GFS is always right at 384 hrs. Ridge to the north weakening a little. Yep, right to Houston. Going fill up my four 5-gal gas cans now and buy all the water in Kroger.

Let's not be hasty.
The first, and most important, question is: do you have vacation plans?

[Blown Away]

12Z EPS very bullish, same for GEFS

https://uploads.tapatalk-cdn.com/20220821/a458fa5d0f5d80bd9a2ea3123ee70580.jpg

https://uploads.tapatalk-cdn.com/20220821/0bb12595109c6146d4db6f13b60b156f.jpg


Sent from my iPhone using Tapatalk

So basically everything that comes off Africa is OTS according to the EPS.

It changes every model run and will continue until this TW reaches @60W in @8 days.

[NotSparta]

https://www.tropicaltidbits.com/analysis/models/gfs-ens/2022082112/gfs-ememb_lowlocs_atl_46.png

Very intense ensemble support on the 12z GEFS. Note the blue high pressure anomalies anchored around FL and to the east. Should keep these moving to the west in the short term.

That's not high pressure anomalies, the blue shading just represents lower spread in pressure values (so more confidence)

[skyline385]

12Z EPS very bullish, same for GEFS

https://uploads.tapatalk-cdn.com/20220821/a458fa5d0f5d80bd9a2ea3123ee70580.jpg

https://uploads.tapatalk-cdn.com/20220821/0bb12595109c6146d4db6f13b60b156f.jpg


Sent from my iPhone using Tapatalk

So basically everything that comes off Africa is OTS according to the EPS.

It changes every model run and will continue until this TW reaches @60W in @8 days.

It does but surprisingly there has been an ongoing trend with the EPS that more members seem to be recurving which is odd cause typically the EPS has a ridge bias.

[skyline385]

https://www.tropicaltidbits.com/analysis/models/gfs-ens/2022082112/gfs-ememb_lowlocs_atl_46.png

Very intense ensemble support on the 12z GEFS. Note the blue high pressure anomalies anchored around FL and to the east. Should keep these moving to the west in the short term.

That's not high pressure anomalies, the blue shading just represents lower spread in pressure values (so more confidence)

Think he was talking about the individual high pressure members in blue located around FL. Like you said, the lower spread would suggest that there is more confidence in the ridging over Florida.

[Hammy]

So basically everything that comes off Africa is OTS according to the EPS.

It changes every model run and will continue until this TW reaches @60W in @8 days.

It does but surprisingly there has been an ongoing trend with the EPS that more members seem to be recurving which is odd cause typically the EPS has a ridge bias.

They're still coming off at a higher latitude--anything that exits close to or north of 15 isn't making it across the Atlantic.

[wxman57]

Major hurricane to strike Houston/Galveston Sept. 8th. No doubt about it, the 12Z GFS is always right at 384 hrs. Ridge to the north weakening a little. Yep, right to Houston. Going fill up my four 5-gal gas cans now and buy all the water in Kroger.

Is that spawning of the central American wave?

I can trace the 850mb vorticity to over central Africa. GFS has it moving off the west coast of Africa Wednesday night.

[aspen]

18z GFS has the same evolution of the second system as prior runs:

1.) A relatively north wave emerges on August 25th

2.) Another wave, this one much further south, emerges within 24 hours

3.) The two waves merge and seemingly form some area of rotation

4.) That southern wave has the dominant vorticity and rotates within the broader envelope. This is what causes it to get drawn north a bit but then return to a lower latitude

5.) A TC develops either during or after the max vorticity gets drawn up north

[Visioen]

Really curious how this will pan out. Gfs with some consistency at least.

[aspen]

GFS has a major heading north of the islands this run. Probably OTS, because not a single run has managed to make landfall north of Florida.

[Carolinagirl18]

GFS has a major heading north of the islands this run. Probably OTS, because not a single run has managed to make landfall north of Florida.

NC will probably get this one.

[SoupBone]

GFS has a major heading north of the islands this run. Probably OTS, because not a single run has managed to make landfall north of Florida.

NC will probably get this one.

If that's the same one from last run, the GFS is all over the place. That last run was headed toward Texas. We need like another week.

[Teban54]

GFS has a major heading north of the islands this run. Probably OTS, because not a single run has managed to make landfall north of Florida.

NC will probably get this one.

If that's the same one from last run, the GFS is all over the place. That last run was headed toward Texas. We need like another week.

384-hour model runs for a wave that has not yet left Africa are not good for tracks, anyway. Irma and Florence are prime examples of this.

The development signal is more important at this stage. Of course, it's entirely possible that models drop development after splash down, but at least this time it's more believable, as the preceding wave helps clear out SAL.

[AJC3]

I know it is from a wave west of the one now just west of the CVs and may be the one recently near 40W: ICON keeps developing a low just E of the L Antilles that I can't find on any of the other models. Anyone else notice this?

I took a look at that 18Z ICON run. It shows a weak spot low near 7N 51W in about 6hr, then gradually spins it up and moves it slowly WNW-NW toward the LA. It appears to come from the ITCZ, just ahead of the wave near 47/48W. There's very little deep convection in that part of the ITCZ right now, so I'd bet the farm it's some sort of bogus feedback issue with the model. TBH, I hardly ever look at the ICON - my first impression was that its output is generally...

[REDHurricane]

18z GFS has the same evolution of the second system as prior runs:

1.) A relatively north wave emerges on August 25th

2.) Another wave, this one much further south, emerges within 24 hours

3.) The two waves merge and seemingly form some area of rotation

4.) That southern wave has the dominant vorticity and rotates within the broader envelope. This is what causes it to get drawn north a bit but then return to a lower latitude

5.) A TC develops either during or after the max vorticity gets drawn up north

Here is my attempt at making a gif highlighting each wave -- the red wave is the current NHC area of interest, the green wave is the northern wave, and the purple wave is the southern wave. The green wave moves off Africa around 00z August 24th, the purple wave comes around 24 hours after; the purple wave moves faster than the green wave and the two end up merging around a week from today.

[Teban54]

18z GFS has the same evolution of the second system as prior runs:

1.) A relatively north wave emerges on August 25th

2.) Another wave, this one much further south, emerges within 24 hours

3.) The two waves merge and seemingly form some area of rotation

4.) That southern wave has the dominant vorticity and rotates within the broader envelope. This is what causes it to get drawn north a bit but then return to a lower latitude

5.) A TC develops either during or after the max vorticity gets drawn up north

Here is my attempt at making a gif highlighting each wave -- the red wave is the current NHC area of interest, the green wave is the northern wave, and the purple wave is the southern wave. The green wave moves off Africa around 00z August 24th, the purple wave comes around 24 hours after; the purple wave moves faster than the green wave and the two end up merging around a week from today.

https://media.giphy.com/media/ylsmxMQCq3AZiT79HB/giphy.gif

If the wave merging happens like GFS suggests, the GEFS and EPS ensemble members that intensify in the middle of the MDR are suspect. One would expect this to result in a more westward track similar to the operationals. Just my amateur guess.

[Blown Away]

Todays GFS/Euro ensembles suggest the most likely outcome is a safe recurve OTS. GFS keeps delaying slightly in the long range today. Especially with the TW’s moving off Africa at a high latitude, very hard to make it across when starting @15N.

[Cpv17]

18z GFS has the same evolution of the second system as prior runs:

1.) A relatively north wave emerges on August 25th

2.) Another wave, this one much further south, emerges within 24 hours

3.) The two waves merge and seemingly form some area of rotation

4.) That southern wave has the dominant vorticity and rotates within the broader envelope. This is what causes it to get drawn north a bit but then return to a lower latitude

5.) A TC develops either during or after the max vorticity gets drawn up north

Here is my attempt at making a gif highlighting each wave -- the red wave is the current NHC area of interest, the green wave is the northern wave, and the purple wave is the southern wave. The green wave moves off Africa around 00z August 24th, the purple wave comes around 24 hours after; the purple wave moves faster than the green wave and the two end up merging around a week from today.

https://media.giphy.com/media/ylsmxMQCq3AZiT79HB/giphy.gif

If the wave merging happens like GFS suggests, the GEFS and EPS ensemble members that intensify in the middle of the MDR are suspect. One would expect this to result in a more westward track similar to the operationals. Just my amateur guess.

I agree. I wouldn’t expect an OTS solution here. Often times when waves are still over Africa or just come off the coast, operationals and ensembles often times have them going OTS and then adjust further south and west as time goes on.

[wxman57]

I feel better now. 18Z GFS keeps the major hurricane out of the Gulf. I'm sure it's correct THIS time. Looking like a storm-free August. No named storm since early July.