ATL: ISAIAS - Models

[ronjon]

You meant the 12z ICON...

[HurricaneFrances04]

Not even windshield wiping. Models have shown a NW track and the invest kept speeding west. If anything, it's finally capitulating to what the Euro showed days ago.

[Hypercane_Kyle]

12z GFS consolidating faster, further north compared to previous runs.

[tolakram]

Been years since last post, so hello everyone! From Orlando and see the first cone came out and shows it coming into Florida. Is this something we should worry about meaning a MH.

No, this won't become a major.

Even pro mets will qualify their statements some level of humility, regardless of how sure they are. Do not make, and everyone please do not take seriously deterministic statements like this. The question of should I be worried should always be answered the same way: You should be prepared already (as you should be every season), and then keep an eye on it. No model has done very good this year, even 5 days out. Last Tuesdays run of the Euro showed Hannah as a wave into the Texas coast.

There is no way to know at this time how strong the storm will be, or the exact path.

[Blown Away]

12z GFS consolidating faster, further north compared to previous runs.

Also moving faster which hopefully keeps intensity down, but may mean a farther W track.

[Shell Mound]

12z GFS consolidating faster, further north compared to previous runs.

The key is that the 12Z run shows greater organisation within the next day and a half vs. previous runs, thus breaking the earlier trend toward a weaker system. This could also mean the difference between a system that gets sheared apart by the TUTT vs. one that manages to “create its own environment” on account of its being more organised by the time it nears Puerto Rico and the USVI. Additionally, note that the latest run shows the southern vortex becoming dominant and then pirouetting northward as the old, northern vortex gets absorbed.

Edit: shear vectors look much more favourable by day three vs. earlier runs as the system enters the southeastern Bahamas.

[toad strangler]

A hair more defined at 102 hrs than 6z on the GFS

[aspen]

12z GFS is the strongest GFS run in a while, but it still tries to kill off PTC-9 in the Bahamas by day 4/5.

[Blown Away]

12z GFS slightly faster and comes closer to SFL, but continues to show at best a TD/Minimal TS.

[SFLcane]

There was no 06z HWRF or HMON.

[toad strangler]

CRAWLING on 12z GFS

[Siker]

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 24 HOURS
FORECAST POSITION AT T+ 24 : 15.3N 61.1W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 29.07.2020 24 15.3N 61.1W 1006 36
0000UTC 30.07.2020 36 16.7N 63.7W 1004 40
1200UTC 30.07.2020 48 18.0N 66.5W 1003 46
0000UTC 31.07.2020 60 18.9N 68.6W 1002 46
1200UTC 31.07.2020 72 20.0N 70.6W 1002 45
0000UTC 01.08.2020 84 20.8N 73.6W 1002 44
1200UTC 01.08.2020 96 21.9N 75.5W 1003 40
0000UTC 02.08.2020 108 23.3N 76.8W 1001 45
1200UTC 02.08.2020 120 24.9N 77.7W 996 47
0000UTC 03.08.2020 132 26.5N 78.1W 990 51
1200UTC 03.08.2020 144 28.1N 78.5W 985 53

[Shell Mound]

12z GFS slightly faster and comes closer to SFL, but continues to show at best a TD/Minimal TS.

Interestingly enough, the circulation remains rather symmetrical for nearly four days—seemingly sufficient to “split the (weak) TUTT”:

[TheStormExpert]

12z GFS consolidating faster, further north compared to previous runs.

I’ll believe the GFS when it starts gaining latitude or at least changes its heading.

[jconsor]

 https://twitter.com/yconsor/status/1288144014923968519

[toad strangler]

12z poofing this right of the SE FL Coast @126hrs

[SFLcane]

Even a TS in the Bahamas is playing with fire as those waters are extremely warm.

[gatorcane]

12z poofing this right of the SE FL Coast @126hrs

Yet the model shows a very favorable upper-level wind pattern that sets up as it approaches SE Florida. Hot water, slow moving, system. Hmmm...

[Shell Mound]

https://twitter.com/yconsor/status/1288144014923968519

Personally, I would blend (combine) the GFS-Parallel, HAFS-B, and HWRF/HMON for intensity and the ECMWF/EPS for the synoptic pattern, then put them all together.

[SFLcane]

Recon almost to PT9.