Cat 4 likely, Cat 5?

[MGC]

How often do NHC discussions bring up the possibility of a hurricane reaching Cat 5? Hardly ever this far out. While it is certainly possible for Frances to reach Cat 5 I have my doubts as a Cat 5 cane is a fairly rare occurance. Frances should certainly reach Cat 4. This hurricane is going to make millions of people nervous and Franches will be the story of the week next week. Sure is looking like a EC threat.......MGC

[Air Force Met]

IT's real rare that they would say something like that. I think they are concerned....and perhaps Charley has made them a little gun-shy.

[canegrl04]

They have good reason for bringing it up. There is no shear in her path,and the SST's are going to be 86 degrees for a good portion of the Atlantic from the Islands,to the waters off Florida,and in the Gulf

[B-Bear]

I think they have reason to be concerned. They initially were calling for slow and steady intensification, due to a dry environment. But Frances didn't care. She exploded DESPITE the dry environment. And now she doesn't have one single factor predicted to inhibit her development other than eye wall cycling. Although I'm scared for the people that will have to deal with her, I'm excited to be able to watch this happen. Only the laws of physics will limit this storm's power, it seems.

[wx247]

It looks to be a monster... no matter the cat. it is when it hits land.

[Stormsfury]

One of the issues here is that once Frances begins to recurve back WEST, historically, conditions seem to become favorable for some rapid intensification b/c of several factors ... and there generally isn't anything that hinders storm development ...

See ...

Andrew
Isabel
etc.

SF

[Hyperstorm]

One of the issues here is that once Frances begins to recurve back WEST, historically, conditions seem to become favorable for some rapid intensification b/c of several factors ... and there generally isn't anything that hinders storm development ...

See ...

Andrew
Isabel
etc.

SF

Excellent point, Stormsfury. If the hurricane is in a westerly course by the time it approaches Florida, it will most likely remain a powerful storm. We can also add to your list...Allen, Gilbert in the Caribbean...Floyd, Gert, Edouard and so many others in the Atlantic. Westerly heading storms tend to strengthen or remain extremely strong until they start recurving, or approach strong UL winds.

Rather concerning point for Florida...

[hurrmia]

that area east of miami is very warm water no tropical system have pass by their yet so water are round 85 to 90

[Stormchaser16]

I still think because of the rapid intensification it is POSSIBLe and i stress possible, that it may peak well before landfall and could actually weaken before landfall, like Lily,Isabel and Floyd(namely isabel and floyd since that is closer to where Frances is now)

[lilbump3000]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

[btangy]

I think the NHC is very wary of the SHIPS/GFDL intensity forecasts, and going with their instinct that Frances will go through a rapid phase of deepening.

http://grads.iges.org/pix/hurpot.html

Potential intensity plots show it moving into a higher area of pot. intensities, so in general, conditions are becoming even more favorable if shear stays at bay (which it is apparently doing so).

[crazycajuncane]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

I was going to post the same thing lilbump! We got really lucky that the tropical system the week before Lili cooled off the waters. The system that hit the week before.... I forget the name.... hit exactly a week before and sucked a lot of juice. This storm on the other hand has no one driving in front him but warm waters.

[B-Bear]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

I was going to post the same thing lilbump! We got really lucky that the tropical system the week before Lili cooled off the waters. The system that hit the week before.... I forget the name.... hit exactly a week before and sucked a lot of juice. This storm on the other hand has no one driving in front him but warm waters.

I find your avatar disturbing. )

[PurdueWx80]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

I was going to post the same thing lilbump! We got really lucky that the tropical system the week before Lili cooled off the waters. The system that hit the week before.... I forget the name.... hit exactly a week before and sucked a lot of juice. This storm on the other hand has no one driving in front him but warm waters.

There have been several studies which show Lili's weakening had very little to do with "cool" waters. The waters weren't actually that cool, and were very much capable of supporting a Cat 3 or 4. Most of the weakening had to do with either shear or dry air being entrained into the system. Isidore was only a tropical storm when she made landfall - TStorms really don't do much to disturb the surface water. Just wanted to clear this up.

[spaceisland]

If ever an environment could be devised by models for Cat 5 development, wouldn't it look just like the current picture for Frances? ie high SST's, low shear, little land interaction, no other systems concurrent or having traveled the projected path...

... It seems reasonable to at least suggest the possibility of a Cat 5 when there isn't anything to prevent it... and a Cat 5 is rare primarily because this set-up is so rare... Right?

[Hyperstorm]

If ever an environment could be devised by models for Cat 5 development, wouldn't it look just like the current picture for Frances? ie high SST's, low shear, little land interaction, no other systems concurrent or having traveled the projected path...

... It seems reasonable to at least suggest the possibility of a Cat 5 when there isn't anything to prevent it... and a Cat 5 is rare primarily because this set-up is so rare... Right?

Actually, that's only half-true. There have been COUNTLESS times when conditions do appear to be VERY FAVORABLE, but systems fail to strengthen to their maximum potential intensity. The reasons are not well understood at this time, hence many research investigations are being conducted currently to determine that sometime in the future.....hopefully.

[NorthGaWeather]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

I was going to post the same thing lilbump! We got really lucky that the tropical system the week before Lili cooled off the waters. The system that hit the week before.... I forget the name.... hit exactly a week before and sucked a lot of juice. This storm on the other hand has no one driving in front him but warm waters.

There have been several studies which show Lili's weakening had very little to do with "cool" waters. The waters weren't actually that cool, and were very much capable of supporting a Cat 3 or 4. Most of the weakening had to do with either shear or dry air being entrained into the system. Isidore was only a tropical storm when she made landfall - TStorms really don't do much to disturb the surface water. Just wanted to clear this up.

It had alot to do with Dry air entrained and cool waters. Several NOAA scientists really believe that theory while others say it was shear. All three played a role and yes cooler waters played heavily on this as Lili was likely a Cat 5 before it weakend. Recon found that 211 MPH gust just above the surface and something over 225 a few thousand feet up.

[PurdueWx80]

Speaking of one of them systems. Central Lousiana would have been done for if it wasnt for the tropical storm before Lili. Lili weakened because of the waters that were cooled off of the coast of louisiana, other than that she would have been a cat. 4 coming into louisiana.

I was going to post the same thing lilbump! We got really lucky that the tropical system the week before Lili cooled off the waters. The system that hit the week before.... I forget the name.... hit exactly a week before and sucked a lot of juice. This storm on the other hand has no one driving in front him but warm waters.

There have been several studies which show Lili's weakening had very little to do with "cool" waters. The waters weren't actually that cool, and were very much capable of supporting a Cat 3 or 4. Most of the weakening had to do with either shear or dry air being entrained into the system. Isidore was only a tropical storm when she made landfall - TStorms really don't do much to disturb the surface water. Just wanted to clear this up.

It had alot to do with Dry air entrained and cool waters. Several NOAA scientists really believe that theory while others say it was shear. All three played a role and yes cooler waters played heavily on this as Lili was likely a Cat 5 before it weakend. Recon found that 211 MPH gust just abover the surface and something over 225 a few thousand feet up.

I mostly agree with you - it was a combination of all three. The most recent study I've read shows that only 27% of the weakening can be attributed to shear and slightly cooler waters, most of that being shear though. That leaves a lot of room for dry air (and other things?). My thesis involves preparing MODIS high-res PWV data for an assimilation into the 4-km WRF, and Lili is one of our case studies. We'll also be using GPS and SSM/I PWV data as well. Should be interesting to see what our results are.

[spaceisland]

If what Hperstorm says is true... that there have been countless times when conditions appeared very favorable, but full development did not take place, then it just becomes more clear that additional research, as suggested, is very necessary. Development or lack thereof is a matter of physics, not chance, so there must still be major factors which we just do not yet comprehend! (and which we must clearly try to unravel).

[frankthetank]

I think the mystery of storms and why they seem to do strange and unpredictable things is what keeps many, like me, so addicted to weather....so many variables at play...02cents