ATL: IRMA - Models

[BYG Jacob]

18z GFS... 96 hours... @17N/55.1W... NHC 96 hour position is 17N/56.5W

Its gonna have Irma plow through a ridge again isn't it?

[AxaltaRacing24]

18z GFS... 96 hours... @17N/55.1W... NHC 96 hour position is 17N/56.5W

Its gonna have Irma plow through a ridge again isn't it?

Most likely. Not like that's going to magically change now.

[meriland29]

it looks like she is booking it more NW, the gap between 12z and 18z getting wider as she heads more N.

[SouthFLTropics]

If that trough digs as much on this run as the Euro showed it is really going to pump up the ridge North of Puerto Rico.

[BYG Jacob]

18z GFS... 96 hours... @17N/55.1W... NHC 96 hour position is 17N/56.5W

Its gonna have Irma plow through a ridge again isn't it?

Most likely. Not like that's going to magically change now.

Sigh, oh GFS.

[Blown Away]

GFS a little slower than Euro, so we will see if Wxman57's idea that the ridge will build in day 11-12??

[Ken711]

How much we much will recon help with the track once it begins?

[RL3AO]

Central US trough stronger this run when looking at 500 mb and PV.

[meriland29]

I don't see why she would be making a solid NW turn seeing the map, but then again, I am not a pro-met, but I do understand enough to be scratching my head...

[SouthFLTropics]

18z GFS at 114 vs. 12z Euro at 120

[AxaltaRacing24]

Still slightly north of the 12z position but more ridging in place. How do we get to NE this time?

[SouthDadeFish]

One interesting difference between the 18Z GFS and 12Z Euro is the upper-level low NW of Irma. The EC moves that off much quicker to the west by 120 h, whereas the GFS keeps it closer. The associated cyclonic flow due to this cutoff likely helps push Irma just a bit NE of the Euro position. It would also have an effect on the ridge to the NW too. Something to keep an eye on as we go forward. This could have a big impact on the track of the TC relative to the Antilles.

[RL3AO]

I don't see why she would be making a solid NW turn seeing the map, but then again, I am not a pro-met, but I do understand enough to be scratching my head...

Look at the tilt of the trough and ridge. WNW movement makes perfect sense. Now, that doesn't mean I think the GFS is right.

[AxaltaRacing24]

[Blown Away]

If you click the previous GFS runs you can see the trough moves slightly W with each run...

[AxaltaRacing24]

Lots of red

[SouthFLTropics]

12z Euro at 144 Hours vs. 18z GFS at 138 Hours

[SouthFLTropics]

Hours 144 to 168 will be very telling. Does the trough cut off or does it lift out as fast as what the Euro showed earlier.

[AxaltaRacing24]

12z Euro at 144 Hours vs. 18z GFS at 138 Hours

The GFS ridge is stronger yet the system is still that much farther north? That is what I am skeptical about.

[RL3AO]

Shades of 5 sigma height anomalies with SE US through. Much stronger and SW this run. I think the GFS is still too far north through 5 days.