ATL: IRMA - Models

[BucMan2]

Robbielyn- Assuming the path stays the same as of today, my thinking would be that we would get at most some squally weather
from the outer bands with winds 20-25 mph. Of course ant deviation west could change that in a heartbeat. But that is the way I see at
this moment. Of course that is my opinion, but as always check with your local weather service for updated info

[p1nheadlarry]

According to some posters, some TV Mets and social media posters have used that as their validation for apathy earlier today.

Localized conditions can be sketchy on the global and even mesoscale models. But it's possible that a farther shift west toward the keys would cut back on the potential structural damage in Miami/Miami Beach. The Everglades and Big Cypress won't really knock anything back substantially, but every mile inland does absorb some of the energy. I'm not wishing or hoping for a track farther west, but a hit on the SW Tip of FL might be slightly better than a hit on the southern tip or over on the SE Coast as it relates to population centers and specifically Miami up to West Palm Beach. Cat 2/3 effects are generally preferable to Cat 4/5 where you jump from extensive to catastrophic structural damage. Consider that Florida is less than 100 miles across at Miami's latitude and roughly about 110 miles from Hollywood across to Naples. Depending on the size of the eye and inner core at landfall, at some point west things start improving for the SE FL Coast.

What's been concerning to me is intensification in the FL Straits. Many models have shown some of the lowest pressures in the 4 day period on approach to FL Landfall. How big and how wide the inner bands go will make a difference if it's deepening. Consider metro Miami has roughly 5 million people. Naples has probably 35,000 in that general area. Ft. Meyers/Cape Coral close to 300k and maybe 700-800k people up toward Sarasota which I think is a bit far north and west for landfall but is just being used for comparison purposes. There's a lot of high end real estate on both sides of the state, but there is substantially more on the SE Coast than the SW Coast.

One thing I haven't really seen talked about is the topography of southern Florida. Factor in the shallow water of the everglades and Lake Okeechobee and I don't think Irma will weaken the same way it would if it came ashore in a different location. Was it Andrew or Katrina that maintained strength or actually strengthened a little when it came inland?

Katrina.

Maybe. Andrew made landfall at 926 mb on Elliott Key, 922 after Homestead.

[p1nheadlarry]

Has Savannah ever been hit wirh a 3 or 4?

Yes. However it was 119 years ago.

[otowntiger]

I live in Hernando county 40 mi nw of Tampa. if current nhc or euro track verifies, what conditions wind wise would we get over here and how many inches of rain? I haven't been able to watch bay news 9 to find out. I love that channel. bucman? or Ronjon?

Go to this website: https://weather.us/forecast/xl and type in the name of your town. You'll be able to see forecast wind speeds, rainfall amounts, and lots of other stuff from all the models so you can compare easily.

That's a really cool website! thanks for sharing!

[MatthewsRevenge]

The cone at 5pm is at the tip of southern NC but almost all of SC is covered by this cone now (don't think it was at 2 pm). I'm guessing NHC is going with what Euro is seeing?

[forecasterjack]

I live in Hernando county 40 mi nw of Tampa. if current nhc or euro track verifies, what conditions wind wise would we get over here and how many inches of rain? I haven't been able to watch bay news 9 to find out. I love that channel. bucman? or Ronjon?

Go to this website: https://weather.us/forecast/xl and type in the name of your town. You'll be able to see forecast wind speeds, rainfall amounts, and lots of other stuff from all the models so you can compare easily.

That's a really cool website! thanks for sharing!

no problem! feel free to look around at all the other stuff we have, there's a lot! Let me know if you have any questions about the site!

[PandaCitrus]

Something I've noticed in the wind reports in the islands and the damage impacts is Irmas core of nasty winds is confined to the eyewall. Outside of the 30 mile eye is a 10 to 12 mile wide band that contains the cat 4 and cat 5 winds. Outside of this band you quickly drop off to Cat 1 winds and below.

This means you have to think of Irma as a 50 mile wide tornado. Where is that swath going to hit? The models that have it going up the spine of the state would effect the least amount of people with the strongest winds. The current euro is a worst case scenario. It puts 6 million people in that swath.

[otowntiger]

As a whole, the 12Z Euro ensembles shifted a touch west through 5 days. Most are clustered on FL and the FL keys. Numerous ensemble members hit Cuba before heading into the SE Gulf.

Are we at the point now with the very good agreement on the major models that the track is getting pretty solidified? Do you see where it can still shift significantly one way or the other? In my opinion I think the NHC track won't budge unless significant swings happen in the models, which I think are becoming much less likely. Agree?

[MatthewsRevenge]

So the Cat 4 and 5 winds are at the western side of the hurricane? I'm guessing east is where the rain comes (and then the wind gusts that could bring tornadoes)?

[PandaCitrus]

The cat 4 and 5 winds are in a 10 to 12 mile radius around the eye. Strongest should be northeast quadrant. Weakest is southern eyewall which should be 25 to 30 mph less. It gets tricky with mezovorticies like Andrew. Some of the strongest winds were in homestead and florida city in the southwestern eyewall.

[MatthewsRevenge]

The cat 4 and 5 winds are in a 10 to 12 mile radius around the eye. Strongest should be northeast quadrant. Weakest is southern eyewall which should be 25 to 30 mph less. It gets tricky with mezovorticies like Andrew. Some of the strongest winds were in homestead and florida city in the southwestern eyewall.

Ah OK, gotcha.

[Hypercane_Kyle]

Wonder what impact a stronger-than-expected Katia might have on the track of Irma.

[Kingarabian]

18z GFS hours 00->06:

[Kingarabian]

18z GFS initializes a bit more south:

[MatthewsRevenge]

I was gonna say the same thing. GFS seems to be south in 18z.

[Kingarabian]

18z GFS hour 12:



Slower/east of 12z

[Kingarabian]

18z GFS hour 18:

[MatthewsRevenge]

[Kingarabian]

18z GFS hour 24:

[Kingarabian]

18z GFS trend at hour 24: