ATL: IRMA - Models

[TheStormExpert]

I know the GFS has overestimated troughs for years now, but has this new upgraded version of it done so even more?

[CourierPR]

Listen to alonyo, he is more credible than that gfs run..hopefully he is wrong, o doubt it

What is Alyono saying?

[Bamagirl2408]

I'm calling BS, it has Irma heading wnw which it's not, it's still heading at a decent pace due west.

Post #3970 on discussion board from Michele B shows satellite loop of wnw movement.

It is barely north of west. On last update moved .2 north .7 west

[emeraldislenc]

This model does not look good for NC. Let!s see what happens the next few days.

[ava_ati]

I can't believe the GFS continues to trend east, when the NHC and the UKMET is trending west... Very strange indeed.

Not really, gfs gets a win sometimes, nhc track has been rock solid on irma, follow it

The exact point I was trying to make.

[Bamagirl2408]

Listen to alonyo, he is more credible than that gfs run..hopefully he is wrong, o doubt it

What is Alyono saying?

He doubted validity due to this run taking it north of islands which seems unlikely.

[AJC3]

This is insane. No one know where it's going. I had hoped by tonight we would have some clarity.

Any increase in forecast confidence witll be SMALL and INCREMENTAL. There will be no epiphany in the forecast track with a singular model run. In the context of the global models, their respective ensembles, and their consensuses, or more appropriately, THEIR LACK THEREOF...there is no such thing as GOOD, BAD, BETTER, or WORSE news based on a single model run. We're simply too far out. All options from just west of Florida to just east, and everything in between, are equally plausible at this point, and will very likely remain so for several more days.

At this point, potential land interaction with the large islands of the GA is a much bigger caveat than at which longitude Irma eventually turns north.

[TheStormExpert]

Listen to alonyo, he is more credible than that gfs run..hopefully he is wrong, o doubt it

What is Alyono saying?

That this GFS run is likely garbage.

[AxaltaRacing24]

Listen to alonyo, he is more credible than that gfs run..hopefully he is wrong, o doubt it

What is Alyono saying?

That this GFS run is likely garbage.

I highly doubt it even goes that north of the islands. What was the GFS doing?

[MatthewsRevenge]

NHC has the cone (of uncertainty) extending to west FL and the east GC. I don't expect NHC to suddenly change because UK and 18z GFS has this going east to the Carolinas. I'm guessing since this storm is so widespread, they're hitting at all angles to see where it would stick. Euro did too for a while before it went back west. GFS has been going back and forth throughout all of this.

[txrok]

This is insane. No one know where it's going. I had hoped by tonight we would have some clarity.

there is no clarity with hurricanes.

[AutoPenalti]

Just saw the GFS run, just lol.

Still siding with the Euro although I feel that it's still a bit West biased.

We'll see.

[tolakram]

NHC has the cone (of uncertainty) extending to west FL and the east GC. I don't expect NHC to suddenly change because UK and 18z GFS has this going east to the Carolinas. I'm guessing since this storm is so widespread, they're hitting at all angles to see where it would stick. Euro did too for a while before it went back west. GFS has been going back and forth throughout all of this.

Remember the cone is a fixed size updated yearly based in average NHC forecast errors. It;s a little smaller every year but during the year it is a fixed size, a circle placed around the forecast point.

[HDGator]

Question for the experts regarding Irma's pressure vs. the models.

The 12Z Euro initialized Irma with 962mb and maintained it around 960mb until deepening at 144 hours to 938mb.
The 18Z GFS initialized Irma with 926mb and continued deepening it to 900mb at 90 hours and down to 885mb at 120 hours.

This seems like a pretty large discrepancy for the uneducated.

Do the global models account for beta drift? Would this explain the large rightward drift of the GFS vs. Euro?

Most recent recon had Irma at 920mb. Does this affect future model initialization and tracks?

[MatthewsRevenge]

NHC has the cone (of uncertainty) extending to west FL and the east GC. I don't expect NHC to suddenly change because UK and 18z GFS has this going east to the Carolinas. I'm guessing since this storm is so widespread, they're hitting at all angles to see where it would stick. Euro did too for a while before it went back west. GFS has been going back and forth throughout all of this.

Remember the cone is a fixed size updated yearly based in average NHC forecast errors. It;s a little smaller every year but during the year it is a fixed size, a circle placed around the forecast point.

Good point.

[Sanibel]

Edit

[gatorcane]

18Z NAVGEM noticeably north of NHC through hour 72. Maybe NAVGEM goes east of Florida again.

[AutoPenalti]

Looks like the consensus slips slightly east...

Image please?

[CourierPR]

Looks like the consensus slips slightly east...

There doesn't appear to be any model consensus at this point.

[WeatherHoon]

For those asking where it's going or getting hung up on each model run, you're better off just referring to NHC's cone.