ATL: IRMA - Models

[ronjon]

The real scary thing to us Floridians, besides the fact that we'll likely have a major hurricane hitting the state, is that a difference of 20-30 miles in track or small changes in angle of approach will have such devastating consequences. And lets be honest, no model can predict that with any certainty.

[Frank P]

I remember the early Katrina models showed it curving up in the big bend of Florida. Not buying it

and those models shifted well within 5 days of landfall... never forget watching each model, run after run, shift west... regardless, nothing in the models YET that lets me think that is in the works for Irma.. and that's why we stayed glue to the forums and model runs...

[FixySLN]

I have a hard time buying that NW drive after the Southern Florida landfall. Wouldn't it be more likely that it run back up North through east coast looking for some more energy? Especially taking the cold air into consideration...Nags Head/Va Beach braces for whatever is left of her.

*Disclaimer*

I'm no Met...I don't even like making "predictions". I sometimes post my thoughts for others to see and am in NO way a voice of experience or professionalism.

It's got to go west at some point anyway. Aric was showing the cutoff down in the lower MS Valley which acts to draw it up and pinwheel it back while a surface high from Canada comes down from the north. Straight physics that even under the last run where it went back out and came in near GA/SC Border, it came up and hooked west toward southern Indiana. ECMWF shows it as well but it comes in farther north and on a NW heading through the SE US toward WV/SE Ohio.

More 18Z runs should be out soon.

You may very well be correct, though I have to say I hope not. Historically, the majority of early September systems with a northern jog prior to Florida landfall tend to continue on a NNE track. The exceptions to this rule have been systems making landfall south of Miami and continuing into the Gulf. They can do anything unpredictable at anything regardless of what's going on...we're all just guessing at this point. I'm just using past precedent as reference. Hope it isn't taken as arrogance, argumentative, or ignorant.

[hurricaneCW]

If this run verified to a tee, 3 of the most populated counties in Florida would be almost destroyed, specifically by the western side of the eye wall, and a lot of the population of the immediate areas are lower income around the lake and unfortunately loss of life may be record breaking; god forbid the dyke failed...

I think "destroyed" is a bit much. Not likely to see Cat 5 damage over a three county area.

Storm surge could be massive though with a hurricane of this strength and size, and Florida is as flat as it gets.

[plasticup]

How could it maintain that intensity once it landfalls?

Florida is flat, wet, and not that different from the ocean.

I'm being a little facetious, but only a little. The everglades and such aren't as terrible for a hurricane as the Costa Rican mountains.

[bella_may]

I remember the early Katrina models showed it curving up in the big bend of Florida. Not buying it

That was 12 years ago.

Ok and? We've had plenty of surprise storms since then. Nothing is certain at this point especially since that trough could not be a big of a factor as originally thought

[Steve]

264 hours and Jose is nose-diving in the direction of the D.R. as a large trough passes by overhead to the North. By 288 it's blowing up and in the general position to follow what Irma had done several days ago. No way do I believe the run at this point, but it's a very scary repeat setup.
https://www.tropicaltidbits.com/analysi ... 0&ypos=400

[Ken711]

How could it maintain that intensity once it landfalls?

Florida is flat, wet, and not that different from the ocean.

I'm being a little facetious, but only a little. The everglades and such aren't as terrible for a hurricane as the Costa Rican mountains.

Understood. But if you are considering built up areas like cities, it just seems difficult to see.

[AdamFirst]

So how about the end of that GFS run...sends future Jose in a cyclonic loop and slingshots it west toward the Bahamas...

[GCANE]

Inside 144 hrs now with a little bounce back east.
IMHO, this is going to start to gel now.
At DMAX.

[Evil Jeremy]

This is going to become a statewide evacuation disaster. This the worst case scenario, a catastrophic hurricane running up the spine of the state. If impacts start Saturday, then Hurricane Watches will be issued, at the earliest, Thursday morning, for the Keys/SFL. Today I saw the first signs of the public taking notice, with propane hard to find, water sold out at the supermarkets, and busy gas stations. Tomorrow forward will be a madhouse at the stores. If the GFS and ECMWF are showing the same scenario tomorrow night, I'll need to take a look at my evacuation options.

[Ken711]

Inside 144 hrs now with a little bounce back east.
IMHO, this is going to start to gel now.
At DMAX.

You mean an east trend?

[ronjon]

With the GFS run, Key Largo and Homestead would likely be inundated with massive storm surge. The metro areas would sustain high wind damage but surge may be small. Lake O dike could fail which could cause catastrophic flooding for those communities around the lake. Further north, wind damage, heavy rainfall, and tornadoes would be major impacts all the way up to JAX.

[Steve]

I have a hard time buying that NW drive after the Southern Florida landfall. Wouldn't it be more likely that it run back up North through east coast looking for some more energy? Especially taking the cold air into consideration...Nags Head/Va Beach braces for whatever is left of her.

*Disclaimer*

I'm no Met...I don't even like making "predictions". I sometimes post my thoughts for others to see and am in NO way a voice of experience or professionalism.

It's got to go west at some point anyway. Aric was showing the cutoff down in the lower MS Valley which acts to draw it up and pinwheel it back while a surface high from Canada comes down from the north. Straight physics that even under the last run where it went back out and came in near GA/SC Border, it came up and hooked west toward southern Indiana. ECMWF shows it as well but it comes in farther north and on a NW heading through the SE US toward WV/SE Ohio.

More 18Z runs should be out soon.

You may very well be correct, though I have to say I hope not. Historically, the majority of early September systems with a northern jog prior to Florida landfall tend to continue on a NNE track. The exceptions to this rule have been systems making landfall south of Miami and continuing into the Gulf. They can do anything unpredictable at anything regardless of what's going on...we're all just guessing at this point. I'm just using past precedent as reference. Hope it isn't taken as arrogance, argumentative, or ignorant.

Not at all man, great post. That's what I'm used to seeing too which is why the western component even when GFS had it going into Detroit or Ontario when it landfalled much farther north many runs ago seems so strange. But all the models have that sweep west. If you look at the ensembles or any of the spaghetti plots, it's almost all of them. Upper pattern on the continent I guess. We look more for early season storms to go that route and not in September like you said.

Last we checked in on the NAVGEM, it hit SW FL. It's out to 36 hours and has Irma at 17.75N 61.5W
https://www.tropicaltidbits.com/analysi ... s=0&ypos=0

HWRF is also running and is fairly close to the 12Z model at 42 hours:
https://www.tropicaltidbits.com/analysi ... s=0&ypos=0

[GCANE]

Inside 144 hrs now with a little bounce back east.
IMHO, this is going to start to gel now.
At DMAX.

You mean an east trend?

Previous runs were landfalling on the GOM coast.

Now correlating real well with Euro.

I am pretty sure this nails it +/- 50 miles.

[GeneratorPower]

With the GFS run, Key Largo and Homestead would likely be inundated with massive storm surge. The metro areas would sustain high wind damage but surge may be small. Lake O dike could fail which could cause catastrophic flooding for those communities around the lake. Further north, wind damage, heavy rainfall, and tornadoes would be major impacts all the way up to JAX.

Why are you claiming the dike will fail? No evidence.

[Frank P]

18Z GFS was not an East trend at all, especially up towards GA...

[Kohlecane]

I remember the early Katrina models showed it curving up in the big bend of Florida. Not buying it

Very true but that was 12 years ago models are better now then 2005

[hohnywx]

How could it maintain that intensity once it landfalls?

Florida is flat, wet, and not that different from the ocean.

I'm being a little facetious, but only a little. The everglades and such aren't as terrible for a hurricane as the Costa Rican mountains.

Understood. But if you are considering built up areas like cities, it just seems difficult to see.

https://en.wikipedia.org/wiki/Brown_ocean_effect

[Steve]

So how about the end of that GFS run...sends future Jose in a cyclonic loop and slingshots it west toward the Bahamas...

Bearing down on Long Island, Connecticut, Rhode Island and Massachusetts at 360 hours and landfalls there on a due North heading at 372 hours. That looks like a Category 3 as well.
https://www.tropicaltidbits.com/analysi ... 418&fh=372