ATL: Ex-INVEST 91L - Models

[AutoPenalti]

I am a little confused with this feature at around 90W... is this just a short-wave low or is this originated from the GOM?

[BobHarlem]

Makes it to the Bahamas with a stronger ridge.





The 12z Canadian still curves north before the Caribbean, but is southwest of the 0z.

[AutoPenalti]

This is going to get nasty, that ridge is too strong...

[TampaWxLurker]

Moving WNW thru the Bahamas at 288 hours out, pressure up to 990mb. Dry air and shear doing a number on it.

[Pelicane]

That is a very unusual cutoff low. Forms in the SE, dips down nearly into the gulf (and presumably picks up a wave with it), and then goes north into the Midwest. Tons of ridging traps it.

[LAF92]

This is going to get nasty, that ridge is too strong...

The only consolation is the pressure is rising hopefully it gets shredded

[chaser1]

I am a little confused with this feature at around 90W... is this just a short-wave low or is this originated from the GOM?

https://i.imgur.com/BVy0udX.gif

With a front draped across South/Central Florida, a deep southwesterly flow is already bending surface winds from the southwest. Then, a 1009 low appears around 204 hrs over Yucatan and it quickly moves NE and deepens to 1006 mb south of W Cuba. The whole mess moves north with that weak LLC coming into the Florida W Coast. The LLC appears to dissipate but the larger mid level low moves northwest into the N GOM

Edit/ Correction-
It appears that once the LLC moves north into W Coast Florida.... it is actually a seperate mid level short wave that drops south (or cuts off) originating from the S. Plains. So, there's a couple things going on here.

[IcyTundra]

This run might be GOM bound with that ridge to the north building westward. With how slow this will be moving we will be watching this system for possibly up to 2 weeks.

[AutoPenalti]

Weakens considerably compared to the 06z

[TampaWxLurker]

Landfall hour +312, middle Keys, pressure 989/995 between last 2 frames.

[BobHarlem]

Landfall middle/upper Florida Keys. (Islamorada/Tavernier)


Then Naples/Marco Island

[Pelicane]

GEFS still seems unimpressed, although there was a bit of a shift south.

[IcyTundra]

12Z GEFS only has a handful of members developing but the ones that do take it through the islands. I think the small vortex that could develop for 91L is giving the GEFS issues because of its low resolution

[kevin]

Landfall occurs after +300 hours. Of all the variables, models are often worst with shear forecasts. So whether this'll be a TS or a MH at that stage is highly uncertain. I expect future runs to vary from a weak TS to a high-end MH. What today's models do show with more certainty is a more southern short-term track which as a result places the islands (and potentially the SE CONUS) at a higher risk. If it forms, 91L will likely be a hurricane when it reaches the islands. What state it'll be in by the time (and if) it reaches the US is very dependent on potential landfalls and many other factors. Still it's just one model cycle for an invest. Everyone from the Caribbean to Newfoundland should keep an eye on this one.

[BobHarlem]

exits Florida around Melbourne, somehow stronger (granted that path does take it over Lake O). Looks like another landfall is possible. (edit: Myrtle Beach, Delmarva, and then long island) East coast Rider, effectively.

[SFLcane]

All fun in games with this dollar store version of Irma but that fact we have gotten to this point is a little nerve recking if it sticks .

[Stratton23]

12z GEFS isn’t aggressive, but definitely shifted south, with a couple members very far south , like just north of SA, interesting days ahead with this one

[MEANINGLESS_NUMBERS]

Landfall hour +312, middle Keys, pressure 989/995 between last 2 frames.

I don't think they even bring in the lawn furniture for 995 down there.

[IcyTundra]

12z GEFS isn’t aggressive, but definitely shifted south, with a couple members very far south , like just north of SA, interesting days ahead with this one

GEFS runs at a lower resolution than the GFS. It is looking like this is going to be a pretty small system. I am skeptical of the lack of development from most GEFS members to say the least.

[LAF92]

It feels like the GFS operational and ensembles are completely lost.