ATL: IRMA - Models

[MidnightRain]

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.

The buzz has caught on, especially after Harvey. If I were you I would start taking full preparations by tomorrow, like you said the rush is about to happen.

[Alyono]

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.

the Florida east coast is about as surge prone as the Caribbean. Remember, in the 1926 hurricane, the people did not die due to the surge on Miami Beach. They did because they tried to walk across the causeway in the eye and did not make it across. Biscayne Bay would be an issue, but not sure as much so as if it would come in on an Andrew track

[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

A good comparison would be todays models to 2005s
And then 2005s to 1992s with Andrew lots have changed my friend

[GCANE]

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.

From what I am seeing on Helicity forecast, tornadoes could be severe up to West Palm Beach.

[Frank P]

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.

12z GFS hit south Fl, then started going NNE and exited to the Atlantic near Canaveral up to the GA/SC border...

[FixySLN]

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

Yup, I 100% follow your logic and if we were 48 hours out from landfall I wouldn't have even bothered to bring it up. I just can't be convinced to drink the proverbial koolaid this early. I see the trend as well, I just think they're "early" and we'll see some changes in the next 48 hours. My guess is a fast moving system that makes it's way up the coast after nipping SE FL. Tomm. night should prove to be interesting. I'll keep my foot handy in case it needs to be inserted into my mouth. Hope our friends in SE Florida are being safe and smart either way.

[Digital-TC-Chaser]

may actually be more likely than not if it avoids mountains

It's hard not to think of the Labor Day hurricane when you watch that model run. It's happened before.

nothing like the Labor Day hurricane though. That was basically a large tornado in terms of its size. This one is gigantic! This is a large, WPAC typhoon moving in

Not playing this down, but how many times has the GFS shown sub 900mb on plots
in the Wpac this season. No typhoon has so far.

[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?

Previous runs were landfalling on the GOM coast.

Now correlating real well with Euro.

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

I have a feeling the next Euro run will stay off shore of FL and move a landfall further north to NC.

[JPmia]

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.

This topic belongs in the discussion thread, but that is definitely a risk. It is undergoing repairs right now to upgrade it for Hurricanes. It hasn't been upgraded in a long time. It is a big deal and not talked about much.

[bella_may]

When is the next Euro? 11pm?

[Kohlecane]

Just a question but when will we start seeing amounts of surge projected?

[SouthDadeFish]

18Z HWRF is about half a degree north of 12Z run through 57 hours. It also brings Irma up to a cat 5 in about 48 hours.

[Evil Jeremy]

When is the next Euro? 11pm?

Starts around 1:40am

[robbielyn]

When is the next Euro? 11pm?

2am tomorrow

[Kohlecane]

When is the next Euro? 11pm?

145am EST

[Steve]

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.

I have a feeling the next Euro run will stay off shore of FL and move a landfall further north to NC.

It may indeed. But recall its ensembles were appreciably farther west. And it has been following them pretty routinely. I think there's a better shot that it actually landfalls in South Florida than goes farther east, but I don't have the sampling data nor would I be smart enough to read it anyway.

[RL3AO]

Just a question but when will we start seeing amounts of surge projected?

When watches are issued - probably about 72 hours before landfall.

[eastcoastFL]

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.

Imo the only way we see a failure in the dyke is if it were to be a Harvey type situation where the storm dumps over 50 inches of rain on the lake. This storm should be moving swift enough to not let that happen.

[bohaiboy]

Just a question but when will we start seeing amounts of surge projected?

Guidance for generic storms from NOAA based on Cat 1-5 http://noaa.maps.arcgis.com/apps/MapSer ... ad&entry=1

[RL3AO]

STAY ON TOPIC. TALKING ABOUT DIKE FAILURES HAS NOTHING TO DO WITH THE MODELS.