ATL: IRMA - Models

[johngaltfla]

Yikes:

That's a WOW only because HWRF has been decent on intensity. 917 hitting there? Holy smokes.

[gatorcane]

[forecasterjack]

12Z ECMWF shows Irma's hurricane force wind gusts spanning the entire width of Florida on Sunday. https://weather.us/model-charts/euro/814-w-261-n/gusts-3h-mph/20170910-1800z.html

[Big Easy Breeze]

So late in the game, any change in directional movement for a relatively decent amount of time, will potentially have some significant impact on landfall. Last few hours, a noticeable more west component of overall WNW movement. Does that have any impact on the models? I don't know.

[Nimbus]

So late in the game, any change in directional movement for a relatively decent amount of time, will potentially have some significant impact on landfall. Last few hours, a noticeable more west component of overall WNW movement. Does that have any impact on the models? I don't know.

In the past when a storm weakens while buking up against a ridge they often wobble west a little and since we just had an ERC this isn't surprising. The problem as I see it is that the turn near Florida comes so late in the forecast.

We might get some clues based on a slowdown in forward speed.

As Irma approaches the trough at the western end of the ridging she should lose steering, might almost stall, maybe make some stair step motions to the NW before tracking off to the north.

Should be some signals the seasoned NHC staff will recognize in the last 24 hours before reaching -80W.

[SouthDadeFish]

Still quite a bit of spread with the 18Z GEFS. The mean looks centered on the middle FL keys and very close to the 12Z deterministic Euro.

[Vdogg]

So late in the game, any change in directional movement for a relatively decent amount of time, will potentially have some significant impact on landfall. Last few hours, a noticeable more west component of overall WNW movement. Does that have any impact on the models? I don't know.

Seems to be hitting the forecast points exactly, I think this more Westerly motion is already baked in to the models.

[weathermimmi]

Can someone with met knowledge talk about this trough, is it possible for it to stay below it or it not effect such a ne turn?

[RL3AO]

Can someone with met knowledge talk about this trough, is it possible for it to stay below it or it not effect such a ne turn?

It'll turn it. The absolute farthest west it would go would be along the west coast of Florida. That's very unlikely though.

[gatorcane]

00Z spaghetti. Note Euro not shown:

[Blown Away]

TVCN moved a little more W... NHC likes to follow so maybe another W shift at 11pm...

[weathermimmi]

I remember Hurricane Elaina who did circles in the gulf as they could not get a handle on the ridges that influence and wondered if this could just surprise everyone

[txrok]

I am trying to figure out which would be worse for FL. Either way is not looking pretty.

If it rides up east coast - half in/half out of water - at least the dirty side would be seaward, but storm would be stronger in center - ie. at coastline.
If eye rides coastline, this could be very tragic - but again - dirty side out

If it runs up middle of FL - then the dirty side will be on the east of the eye - again on the coast.

If these models are accurate - whichever way it goes - this is going to be a catastrophe. I really feel for the FL folks. God bless them.

The only thing I see that could save FL right now - would be if this 'perfect storm' nudges a tad more eastward. Maybe we can push it east with our prayers?

[RL3AO]

I remember Hurricane Elaina who did circles in the gulf as they could not get a handle on the ridges that influence and wondered if this could just surprise everyone

Well 1985 was a long time ago. The science has made incredible strides.

[weathermimmi]

Yes, That really makes me feel old !! LOL

Next questions, she seems to go thru ewr pretty easily, I guess we have no way to know if she will be in the middle of that and hope for weakness?

[gatorcane]

I wonder is these west shifts with the models are done. I remember with Matthew they kept shifting west and almost got to the Palm Beach County coastline only in the end Matthew passed a comfortable distance east of Palm Beach. The storm basically went a little east of the models at 48-72 hours out. Every storm is different but just wondering if we will see something similar here too. SE Florida still seems the target zone for the worst weather from Irma.

[Blown Away]

Few more W shifts not good for Keys but maybe keeps core out of downtown Miami...

[PTPatrick]

So if you look at that last spaghetti map, we are down to about a 50 -60 miles swath from the western Everglades to downtown Miami a center path. Even the western edge of that swath is pretty bad for the urban areas with a storm of Irmas size. So many things to watch. But I will say regardless of what wind does SFL is going to have a storm surge for the ages...

[gatorcane]

SFWMD plot 00Z. Models zeroing in on South Florida:

[jlauderdal]

I wonder is these west shifts with the models are done. I remember with Matthew they kept shifting west and almost got to the Palm Beach County coastline only in the end Matthew passed a comfortable distance east of Palm Beach. The storm basically went a little east of the models at 48-72 hours out. Every storm is different but just wondering if we will see something similar here too. SE Florida still seems the target zone for the worst weather from Irma.

Gator, we will be lucky to avoid anything but a direct hit in se fla