ATL: IRMA - Post-Tropical - Discussion

[Hurricaneman]

How intense do you guys think this could become before it just isn't scientifically possible for it to get any stronger? I mean there has to be a threshold right. Have there been any thesis or papers written considering how physically possible it is for a cyclone to become?

There is such a thing as maximum potential intensity: http://wxmaps.org/pix/hurpot.html

Quite scary that according to these maps the MPI is between 135 and 150 knots at Irma's current location. And she is at 155 and strengthening...

I can't fathom if this realizes its potential in the straits that would be a complete disaster of epic proportions

[NDG]

The eye wall currently has winds similar to a moderate EF-4 tornado. 185 mph is ridiculous.

I believe tornadoes are rated based upon the gusts (please correct me if wrong). Thus, the winds are EF5 strength now

And what makes it bad in a hurricane is that those winds are constant for a longer period of time, so more structures end up failing under those conditions.

[jhpigott]

How intense do you guys think this could become before it just isn't scientifically possible for it to get any stronger? I mean there has to be a threshold right. Have there been any thesis or papers written considering how physically possible it is for a cyclone to become?

There is such a thing as maximum potential intensity: http://wxmaps.org/pix/hurpot.html

Quite scary that according to these maps the MPI is between 135 and 150 knots at Irma's current location. And she is at 155 and strengthening...

Just thinking the same thing. Irma (at least as far as wind speed is concerned) has busted thru the "maximum potential intensity" for her current location. UGH . . .

[dukeblue219]

How intense do you guys think this could become before it just isn't scientifically possible for it to get any stronger? I mean there has to be a threshold right. Have there been any thesis or papers written considering how physically possible it is for a cyclone to become?

There is such a thing as maximum potential intensity: http://wxmaps.org/pix/hurpot.html

Quite scary that according to these maps the MPI is between 135 and 150 knots at Irma's current location. And she is at 155 and strengthening...

There's always localized effects and data/model uncertainties of course. But, yes, this is partly why it's unlikely the storm will maintain this strength for long since it's already running full-bore for its environment.

Not that it matters if you get hit by 150mph or 180mph sustained winds anyway....

[Langinbang187]

There is such a thing as maximum potential intensity: http://wxmaps.org/pix/hurpot.html

Quite scary that according to these maps the MPI is between 135 and 150 knots at Irma's current location. And she is at 155 and strengthening...

There's always localized effects and data/model uncertainties of course. But, yes, this is partly why it's unlikely the storm will maintain this strength for long since it's already running full-bore for its environment.

Not that it matters if you get hit by 150mph or 180mph sustained winds anyway....

I mean both 150 and 180 are going to be asbolutely catastrophic but given the choice I'm definitely taking 150.

[Michele B]

for sofla and even people that care to watch online...fyi, max mayfield former nhc director is employed by channel 10 so after you catch general hospital tune into pics from gas stations, publix and home depot

Local 10 Special #HurricaneIrma coverage starts at 3pm today @WPLGLocal10, immediately following @GeneralHospital

Prolly catch online if you are not in east coast area.

[Michele B]

The eye wall currently has winds similar to a moderate EF-4 tornado. 185 mph is ridiculous.

I believe tornadoes are rated based upon the gusts (please correct me if wrong). Thus, the winds are EF5 strength now

And what makes it bad in a hurricane is that those winds are constant for a longer period of time, so more structures end up failing under those conditions.

Yes, husband has become very "fatalistic" over this whole storm.....

[Janie2006]

How intense do you guys think this could become before it just isn't scientifically possible for it to get any stronger? I mean there has to be a threshold right. Have there been any thesis or papers written considering how physically possible it is for a cyclone to become?

I've forgotten the threshold, well, as we currently know it anyway, but I do know that the threshold is higher in the Pacific than it is in the Atlantic.
The only storm I can really currently compare Irma to is Gilbert.

I think the threshold is 200, if that. *Think* is the operative verb here.

[jlauderdal]

for sofla and even people that care to watch online...fyi, max mayfield former nhc director is employed by channel 10 so after you catch general hospital tune into pics from gas stations, publix and home depot

Local 10 Special #HurricaneIrma coverage starts at 3pm today @WPLGLocal10, immediately following @GeneralHospital

Prolly catch online if you are not in east coast area.

btw, if you have roku there is an app called local news now, i was able to watch houston coverage with that app, you can watch numerous local news outlets through country

[znel52]

Irma is the strongest tropical cyclone on planet Earth so far this year is it not?

[GCANE]

The latest GFS has this moving just off shore of FL at about 910 mb until landfall just south of Savannah.
Off course this will change, but a scenario like this would pretty much destroy the coast.
Not just wind and water, but tornadoes as well.

[Blinhart]

The question now is how low the pressure will get and how high will the winds get? Will it get below 900 mb? Will the winds reach 200 MPH?

[Shuriken]

I hear you, Shuriken, but I've never seen a storm maintain that level of intensity for very long, in 60 years of "watching" them.

Allen, David, Mitch. They all went "hard" cat-5 and stayed that way for long periods of time without further eyewall replacement cycles. (And Isabel, even though it bounced around a lot in intensity, never underwent another EWRC after achieving a huge eye.) The structure of these storms, especially those with larger eyes, becomes quite stable and impervious to otherwise deleterious atmospheric effects.

I'm just glad to think it WILL weaken. I HOPE it weakens!

Without the introduction of shear, I do not expect Irma to weaken prior to proximity to Puerto Rico (and, if she doesn't begin gaining latitude very shortly, is going to run over that island). There's no reason for it to.

(One thing that can weaken an unsheared cat-5 over hot water is too much of a good thing: occasionally seen in WPAC and GoM storms such as Ike, is this tendency to slow down and grow to ginormous size while the central core sputters. A hurricane "on the move" with a subtropical high to the north shunting it along does not fall into that category.)

[Extratropical94]

Irma is the strongest tropical cyclone on planet Earth so far this year is it not?

It is. The last TC this strong in terms of wind speed was Super Typhoon Meranti last year.

[Falling Soil]

Here I am sitting in Miami.. praying to God for help.. with the latest vortex message that says 160 knots and 926 mb.. Question: When one of these is available, does the NHC only use this or do they still use satellite, etc. in addition to these?

URNT12 KNHC 051705
VORTEX DATA MESSAGE AL112017
A. 05/16:38:10Z
B. 16 deg 53 min N
058 deg 53 min W
C. 700 mb 2440 m
D. 160 kt
E. 054 deg 14 nm
F. 138 deg 151 kt
G. 054 deg 15 nm
H. 926 mb
I. 9 C / 3066 m
J. 18 C / 3052 m
K. 13 C / NA
L. CLOSED
M. C24
N. 12345 / 7
O. 0.02 / 1 nm
P. AF309 0811A IRMA OB 21
MAX FL WIND 151 KT 054 / 15 NM 16:33:00Z
MAX OUTBOUND FL WIND 148 KT 299 / 16 NM 16:44:30Z
CNTR DROPSONDE SFC WIND 180 / 4 KT
MAX FL TEMP 19 C 062 / 7 NM FROM FL CNTR

[wxmann_91]

I hear you, Shuriken, but I've never seen a storm maintain that level of intensity for very long, in 60 years of "watching" them.

Allen, David, Mitch. They all went "hard" cat-5 and stayed that way for long periods of time without further eyewall replacement cycles. (And Isabel, even though it bounced around a lot in intensity, never underwent another EWRC after achieving a huge eye.) The structure of these storms, especially those with larger eyes, becomes quite stable and impervious to otherwise deleterious atmospheric effects.

Allen went through a bunch of ERC's in the Caribbean (it fluctuated in intensity a lot - check the BT).

David slammed into Hispaniola shortly after it attained Cat 5 status.

Mitch upwelled itself to death.

Isabel, even, went through a couple, though it stabilized with a big eye again each time.

[WAcyclone]

Latest microwave:

[dukeblue219]

SUMMARY OF 200 PM AST...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...16.9N 59.1W
ABOUT 180 MI...290 KM E OF ANTIGUA
ABOUT 185 MI...295 KM ESE OF BARBUDA
MAXIMUM SUSTAINED WINDS...185 MPH...295 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...926 MB...27.34 INCHES

[Shuriken]

The eye wall currently has winds similar to a moderate EF-4 tornado. 185 mph is ridiculous.

I believe tornadoes are rated based upon the gusts (please correct me if wrong). Thus, the winds are EF5 strength now

And what makes it bad in a hurricane is that those winds are constant for a longer period of time, so more structures end up failing under those conditions.

185mph is a mid-range EF3 tornado. EF4 begins at 208mph.

http://www.spc.noaa.gov/faq/tornado/ef-scale.html

[Chris90]

The question now is how low the pressure will get and how high will the winds get? Will it get below 900 mb? Will the winds reach 200 MPH?

I didn't think Irma was going to get as strong as it currently is, so at this point, I'm thinking 200 mph might actually be a possibility. Recon recently measured a 160kt sfmr, so it looks like the winds may still possibly be on the increase.
Absolutely crazy. I still can't believe this storm is putting down the winds it is, especially at this pressure.