GOM: Support Most Intense Hurricane?

[StormScanWx]

I was thinking this morning about how Gilbert in '88 was the most intense Atlantic hurricane until Wilma in '05. Both reached peak intensity in the northwest Carribean Sea, right?

My question is could the Gulf of Mexico support a system stronger than Wilma, the most intense Atlantic hurricane? I thought sometimes SSTs in the GOM are, in fact, warmer than the Carribean, so why hasn't this happened? (yet?) (and by no means am I wishing this to happen, just curious)

Thanks!

-SSW

[x-y-no]

I think it's possible with just the right conditions. Even though the warm layer is generally shallower in the Gulf than in the Caribbean, there's plenty of energy there in the loop current.

Consider the intensification of Katrina from Cat. 1 to Cat. 5 in the Gulf. That wasn't as impressive as Wilma's rapid intensification, but it probably involved pumping at least as much energy into the storm. Put that much energy into a somewhat smaller system (Katrina was really big) and you've got a good chance of getting a rival for the record.

As for why it hasn't happened - I think it's to do with that "with just the right conditions" caveat. Perfect conditions are just not as common in the Gulf as in the Carib.

[Ptarmigan]

The Maximum Potential Intensity (MPI) in the Gulf of Mexico can support a strong hurricane. In fact, for Hurricane Katrina, the MPI was 810 mb with winds around 250 mph. Derek Ortt can explain it better. Wilma formed in water within its MPI, same with Rita. Katrina had a lot more potential.

[wxmann_91]

I remember analyzing Katrina loops, and it was apparent that Katrina, though in very hot water, didn't have much time to strengthen. The initial bout of northerly shear and the ERC took some time away that Katrina could've strengthened. Right after it had that "annular" look (yes I know it never was annular), around 6-18Z on Aug 28, westerly shear and dry air to the west had already began to impact the storm. It had only a 12 hr timeframe to clear that eye from the prior ERC, and mature in the strongest stage.

With better timing, or perhaps had Katrina bombed east of S FL, it would've been a massively intense hurricane. Definitely could've gone sub-900.

Now, onto the question, I think there is a reason why the W Caribbean has thus far fostered stronger hurricanes than the GOM. Simple answer: geography. First of all, the GOM is at a higher latitude, meaning a greater chance of being impacted by shear from midlatitude cyclones. Second of all, the GOM is landlocked. A storm that crosses FL has to first reorganize its inner core before reintensifying, which can take precious time. Third, the stronger steering currents in the GOM will take a strong hurricane across land quicker than in the weak steering currents of the Caribbean. Fourth, the GOM is near a large land mass, the CONUS, meaning that if a hurricane gets too large, it will ingest dry continental air. Not the same for Caribbean (or WPAC for that matter), where nearby landmasses are either islands or relatively small. Finally, the Loop Current, where the high heat potential is, is relatively small. The shelf waters leading to the W Coast of FL and the Gulf Coast extend far out. Thus, a greater chance that storms will hit the shelf waters and start weakening. The waters along the Caribbean coastline are deep, meaning a wider and larger area of extremely high heat potential for storms to tap.

[x-y-no]

I agree, wxmann_91.

Conditions for Katrina were favorable but not optimal. Hard to imagine but she could have been substantially worse.

[Ptarmigan]

I remember analyzing Katrina loops, and it was apparent that Katrina, though in very hot water, didn't have much time to strengthen. The initial bout of northerly shear and the ERC took some time away that Katrina could've strengthened. Right after it had that "annular" look (yes I know it never was annular), around 6-18Z on Aug 28, westerly shear and dry air to the west had already began to impact the storm. It had only a 12 hr timeframe to clear that eye from the prior ERC, and mature in the strongest stage.

With better timing, or perhaps had Katrina bombed east of S FL, it would've been a massively intense hurricane. Definitely could've gone sub-900.

Now, onto the question, I think there is a reason why the W Caribbean has thus far fostered stronger hurricanes than the GOM. Simple answer: geography. First of all, the GOM is at a higher latitude, meaning a greater chance of being impacted by shear from midlatitude cyclones. Second of all, the GOM is landlocked. A storm that crosses FL has to first reorganize its inner core before reintensifying, which can take precious time. Third, the stronger steering currents in the GOM will take a strong hurricane across land quicker than in the weak steering currents of the Caribbean. Fourth, the GOM is near a large land mass, the CONUS, meaning that if a hurricane gets too large, it will ingest dry continental air. Not the same for Caribbean (or WPAC for that matter), where nearby landmasses are either islands or relatively small. Finally, the Loop Current, where the high heat potential is, is relatively small. The shelf waters leading to the W Coast of FL and the Gulf Coast extend far out. Thus, a greater chance that storms will hit the shelf waters and start weakening. The waters along the Caribbean coastline are deep, meaning a wider and larger area of extremely high heat potential for storms to tap.

Very true. The Caribbean does not have any large landmasses and also hurricanes can feed off the moisture from the Pacific. Hurricane Katrina was menacing on August 28th, but then it sheered apart the next day. If it had become a major hurricane off the coast of South Florida, then I think Katrina had the chance to even be stronger than it was.

[StormScanWx]

The Maximum Potential Intensity (MPI) in the Gulf of Mexico can support a strong hurricane. In fact, for Hurricane Katrina, the MPI was 810 mb with winds around 250 mph.

Can you elaborate a bit on this part?

Also, this is drifting from the subject, but could someone shed some insight about why it's less likely to have a category five (SSHS) make landfall on the north central Gulf Coast. Just some guesses, but obviously the water depth gets less as you near the coast, and most of the time SSTs aren't AS warm as say the south GOM or the northwestern Carribean.

Thanks to all who reply, I like information threads like these, I learn a lot!

-SSW

[wxmann_91]

The Maximum Potential Intensity (MPI) in the Gulf of Mexico can support a strong hurricane. In fact, for Hurricane Katrina, the MPI was 810 mb with winds around 250 mph.

Can you elaborate a bit on this part?

Also, this is drifting from the subject, but could someone shed some insight about why it's less likely to have a category five (SSHS) make landfall on the north central Gulf Coast. Just some guesses, but obviously the water depth gets less as you near the coast, and most of the time SSTs aren't AS warm as say the south GOM or the northwestern Carribean.

Thanks to all who reply, I like information threads like these, I learn a lot!

-SSW

I'm not Ptarmigan, but yes, Mr. Ortt did say that the GOM at the time of Katrina supported a 810 mb hurricane, or something like that. Here, take a look at this: http://wxmaps.org/pix/hurpot.html

Reasons for weakening at N GOM:
1) Not SST's, Heat Content... is less. Meaning a strong hurricane traversing through those waters will upwell very cool water just beneath the surface, with ease
2) To get there, it has to be steered by a midlatitude cyclone, which can shear it
3) If there's a drought (like there was in 2005-06), a large hurricane can draw in copious amounts of dry, continental air

[Ptarmigan]

Can you elaborate a bit on this part?

Also, this is drifting from the subject, but could someone shed some insight about why it's less likely to have a category five (SSHS) make landfall on the north central Gulf Coast. Just some guesses, but obviously the water depth gets less as you near the coast, and most of the time SSTs aren't AS warm as say the south GOM or the northwestern Carribean.

Thanks to all who reply, I like information threads like these, I learn a lot!

-SSW

Derek Ortt explains it well about MPI. Dry air from landmass and cooler SST near land causes hurricanes to weaken. 2005 was rather dry for America. Southeast Texas was below average in rainfall when Katrina was around. So it would not surprise me if that contributed Hurricane Katrina's weakening.

[Cyclenall]

Hurricane Katrina was menacing on August 28th, but then it sheered apart the next day.

Nope. Not only was there none to hardly any shear affecting Katrina on the 29th, but to say Hurricane Katrina was sheared apart is totally false.

Katrina Image on 29th

Just a lot of dry air affecting the SW side and land interaction.

I believe a system could one day bomb out excessively in the extreme south GOM and compare up to Wilma or Gilbert. It may have to be quite tiny though.

[Ptarmigan]

Nope. Not only was there none to hardly any shear affecting Katrina on the 29th, but to say Hurricane Katrina was sheared apart is totally false.

Katrina Image on 29th

Just a lot of dry air affecting the SW side and land interaction.

I believe a system could one day bomb out excessively in the extreme south GOM and compare up to Wilma or Gilbert. It may have to be quite tiny though.

I meant it appeared sheered off or better yet it appeared not as impressive. I know it wasn't wind sheer that did it. There was little wind sheer that time. And yes, I would not be surprised if there is a hurricane in the Gulf of Mexico that would be like Wilma or Gilbert.

[Cyclenall]

I meant it appeared sheered off or better yet it appeared not as impressive. I know it wasn't wind sheer that did it. There was little wind sheer that time.

It would be a good idea not to use sheared off if it really didn't just to keep the confusion to a minimum.

[Ptarmigan]

It would be a good idea not to use sheared off if it really didn't just to keep the confusion to a minimum.

I made a bad choice of words. It should be ragged instead, not sheered.

[wxmann_91]

Hurricane Katrina was menacing on August 28th, but then it sheered apart the next day.

Nope. Not only was there none to hardly any shear affecting Katrina on the 29th, but to say Hurricane Katrina was sheared apart is totally false.

Katrina Image on 29th

Just a lot of dry air affecting the SW side and land interaction.

I believe a system could one day bomb out excessively in the extreme south GOM and compare up to Wilma or Gilbert. It may have to be quite tiny though.

Look at water vapor loops. There was dry mid-upper level air moving east, into Katrina. That's shear by definition.