ATL: HERMINE - Models

[USTropics]

00z UKMET shows no development until the Bahamas as well:

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NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 138 HOURS

FORECAST POSITION AT T+138 : 23.1N  74.8W

  VERIFYING TIME     POSITION     STRENGTH        TENDENCY
  --------------     --------     --------        --------
 12UTC 26.08.2016  23.5N  76.3W     WEAK        LITTLE CHANGE

[tarheelprogrammer]

Getting sheared by Fiona on this run.

Yeah just cannot escape Fiona and her presence.

[USTropics]

90L catches up pretty quickly as well:

[SouthDadeFish]

00Z GFS really amplifies the upper-tropospheric ridge over the E CONUS and an anticyclonic wave breaking event begins around hour 120. This then causes an upper-level low to retrograde to the SW impinging southerly shear over 99L once it is near the Bahamas. The aforementioned ridge is significantly more amplified than in previous runs, thus so is the shear from the upper-level low. Nonetheless, the shear isn't too large to prevent genesis altogether on it's own. We'll see if this anticyclonic wave breaking even actually happens...

[Blown Away]

Amazing the consistency of the GFS track run after run...

[JtSmarts]

00Z GFS really amplifies the upper-tropospheric ridge over the E CONUS and an anticyclonic wave breaking event begins around hour 120. This then causes an upper-level low to retrograde to the SW impinging southerly shear over 99L once it is near the Bahamas. The aforementioned ridge is significantly more amplified than in previous runs, thus so is the shear from the upper-level low. Nonetheless, the shear isn't too large to prevent genesis altogether on it's own. We'll see if this anticyclonic wave breaking even actually happens...

Sounds like a very complex scenario is unfolding between (Fiona, 99, 90) and the other atmospheric players on the field.

[Hurricaneman]

Here's my thinking, I think this gets going in a similar area to Erin in 1995 and the Euro seems to be making it stronger every run while the GFS is weaker every run so if I'm a betting man I would go with something similar to Erin in 1995 just not as strong in the GOM

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[Bocadude85]

Well something moves over South/Central Florida in the 216 hour time frame. The GFS has been very insistent on moving whatever this becomes into Florida.

[SouthDadeFish]

00Z GFS shows a much different upper-tropospheric pattern than it did 24 hours ago. Here is the forecast from the most recent 00Z run valid at 12Z Aug 27:

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Compared the forecast from yesterday's 00Z run:

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Previously, an upper-level anticyclone dominated the upper-tropospheric flow near 99L, but now a trough is forecast to impose slightly stronger southerly shear. This difference is possibly one reason why development is no longer forecast in the SW atlantic from the deterministic GFS. These differences are to be expected with a 156/180 hour forecast

[WeatherEmperor]

Well something moves over South/Central Florida in the 216 hour time frame. The GFS has been very insistent on moving whatever this becomes into Florida.

It also keeps 99l north of hispanola. Curious what tonights intensity guidance will show

[LarryWx]

Getting sheared by Fiona on this run.

Yeah just cannot escape Fiona and her presence.

Maybe Fiona is getting her frustrations out for the Euro forecasting debacle of the 2010 version of her (Euro made her a cat 4-5 on several runs hitting US GOM coast but she only ended up as a TC that didn't even make it into the GOM) by making sure she has influence over other systems.

[WeatherEmperor]

00z Canadian coming in much weaker. Has barely a TD in the NW Bahamas before turning NE and slowly gaining strength. Joins the Euro and Gfs with showing barely anything

[p1nheadlarry]

None of the models saw Katrina becoming what she diid this far out,just saying.

She came across as a sleeerp once she left TD10 status.I am watching 99L just from past experience's when they blossom early in the MDR they like to be fish I would bet 50/50.I think Ivan was one of the few that made the track as a cane at a low lat. all the way then turned.

If it ramps up north of Hispaniola/PR, it could be a typical seaboard straddler for the late Aug/early Sep part of the season.

[WeatherEmperor]

It seems so strange to me that near the peak of the season none of the global models really do much with this near the Bahamas. This was one of the areas that most pro mets kept harping on being the most favorable areas to watch for development this season and now magically when a tropical system enters the picture mother nature decides to be unfavorable in this typical development hotspot? Just amazes me

[Hammy]

It seems so strange to me that near the peak of the season none of the global models really do much with this near the Bahamas. This was one of the areas that most pro mets kept harping on being the most favorable areas to watch for development this season and now magically when a tropical system enters the picture mother nature decides to be unfavorable in this typical development hotspot? Just amazes me

I personally think it's a combination of lingering Nino effects and the fact that the MJO's unfavorable phase is camped out over the Atlantic at the moment. I think if we get a similar setup in two weeks or so, it'll probably end up a much stronger system.

[p1nheadlarry]

It seems so strange to me that near the peak of the season none of the global models really do much with this near the Bahamas. This was one of the areas that most pro mets kept harping on being the most favorable areas to watch for development this season and now magically when a tropical system enters the picture mother nature decides to be unfavorable in this typical development hotspot? Just amazes me

I personally think it's a combination of lingering Nino effects and the fact that the MJO's unfavorable phase is camped out over the Atlantic at the moment. I think if we get a similar setup in two weeks or so, it'll probably end up a much stronger system.

We could potentially see a favorable MJO for both primary peak (Sep 10) and secondary peak (Oct 20), that would be interesting. Can't be coincidental, can it

[AtlanticWind]

I wouldn't go crazy over what the models show one day , as if you go back about a week on the gfs it showed nothing
Forming thru the end of the month. Things can change quickly and models are not that great with tropical formation .
It is best to follow the invest and see if shows signs of organizing,and just look to models for SOME guidance.

[USTropics]

ECMWF 00z run has an open wave moving north of PR towards the Bahamas at 96 hours:

[USTropics]

The GFS ensembles really backed off on development of 99L as well:



00z GEFS run:


compared to the 18z run:

[Hammy]

Is there -any- model support remaining that develops this? I'm personally thinking it's a done deal now that nothing comes of it.