ATL GUSTAV: Tropical Depression - Discussion

[cheezyWXguy]

No, it isn't. It's probably just not getting picked up by radar. It is still fully intact on my radar.

It's definitely a weaker side. There's some significant southerly shear. I don't think this will restrengthen to a Cat 5, it might restrengthen a little to a mid-strong Cat 4 or remain relatively steady state. Nothing to sneeze at regardless, still a very strong hurricane.

give it time the southerly inflow is still impacted by cuba 50 miles to the south. she will wrap just fine with this "significant southerly wind shear" she did 8 hours ago.

Yeah i agree...btw didnt the RI that occurred today take place under almost 20kt of shear? If so, Im not so sure this is going to have a problem ascending to cat5 tomorrow. It wont be no Katrina at peak, but I think a stronger than Katrina landfall is possible. I must say though, before it crossed cuba i was considering the fact that it may be developing concentric eyewalls. However, it appears whatever outer eyewall it had before is now gone, likely dissipated by land, with the inner core remaining strong. I do not think that an ewrc will take place before landfall, because a slower/steadier deepening seems more likely tomorrow. Im predicting a peak of about 140 or 145 kt, before slowly weakening down to 120-130kt at landfall.

[wxmann_91]

No, it isn't. It's probably just not getting picked up by radar. It is still fully intact on my radar.

It's definitely a weaker side. There's some significant southerly shear. I don't think this will restrengthen to a Cat 5, it might restrengthen a little to a mid-strong Cat 4 or remain relatively steady state. Nothing to sneeze at regardless, still a very strong hurricane.

give it time the southerly inflow is still impacted by cuba 50 miles to the south. she will wrap just fine with this "significant southerly wind shear" she did 8 hours ago.

With the highest heat content in the basin, Gustav did not reach Cat 5, this was b/c of the shear. No reason to see why a similar scenario will not pan out this time.

WRT to Hyperstorm's post, I'm not convinced this will weaken that rapidly, but I recall Lili back in 2002 which had a similar cloud pattern (almost no outflow on the S/SW Quads). NHC says shear might decrease in 18 hr, we'll see how that turns out.

[Hyperstorm]

This system will HAVE to accelerate its forward speed if it's going to make landfall as a Category 4 as forecast. Right now, upper-level winds on the southern side are starting to approach the system and will impede this system maintaining Category 4 intensity for much longer. You can see on water vapor loops the upper-level shield moving northward VERY rapidly toward the system. That will be GREAT news if I wake up tomorrow morning to a Category 3 or LOWER. That is VERY possible with the way the upper-level winds are impinging heavily on the southern side.

This system is reminding me of the structure/side of Dennis as it was making landfall in 2004. IMO, this is the kind of system we will see in Louisiana - Category 2 or minimal 3 with a similar size to Dennis. Still, something dangerous, but not catastrophic/widespread as some make it seem to be.

In any case, PREPARE for the WORST, but I'm seeing some good things tonight. God Bless all in its path...

I guess the perfect circular CDO and cold cloudtops show its going to weaken significantly overnight.

I can sense your sarcasm.

When a VERY powerful hurricane loses its eye like this system did in such a short amount of time and the southern edge is being impeded by southerly shear which is throwing dry air into it, you WILL see a VERY sharp pressure rise. We saw a very similar situation in 2002 with Hurricane Lili.

I will not be at all surprised if the pressure in this system is now in the 960s and going higher...

[wxmann_91]

Gustav has not been a Cat 5 officially yet so it can't 'restrengthen' to one.

It is currently a mid-Cat 4...and if it remains 'steady state' it will landfall stronger than katrina did.

My bad, I'm worn out today from all the tracking. I mean steady-state for the next 24-36 hr. Weakening is likely thereafter.

[soonertwister]

I want to get peoples opinions on this. I live in Ascension Parish which is just south of Baton Rouge. Anyway our local tv met said we should only experience 35-40 mph sustained winds with gusts reaching 60. Seems pretty low considering how close the center of Gustav will pass, especially if he comes in 50 or so miles further east which then the eye would pass right over me. To help out the I live about 90 miles due north of Cocodrie(as close to coast as can get) which is 30 miles south of Houma

Here is the point forecast for Pierre Part starting at midnight Tuesday morning. The forecast sees a top sustained wind of 98 mph with gusts to 121. This was before the latest NHC update. I suspect the next run will be well over 100 mph with gusts somewhere around the 140 range.

http://forecast.weather.gov/MapClick.ph ... lix&unit=0

[wxmann_91]

\
I can sense your sarcasm.

When a VERY powerful hurricane loses its eye like this system did in such a short amount of time and the southern edge is being impeded by southerly shear which is throwing dry air into it, you WILL see a VERY sharp pressure rise. We saw a very similar situation in 2002 with Hurricane Lili.

I will not be at all surprised if the pressure in this system is now in the 960s and going higher...

I have to disagree there. Gustav lost its eye because it went on land. Decently rough and mountainous land at that.

[cheezyWXguy]

With the highest heat content in the basin, Gustav did not reach Cat 5, this was b/c of the shear. No reason to see why a similar scenario will not pan out this time.

WRT to Hyperstorm's post, I'm not convinced this will weaken that rapidly, but I recall Lili back in 2002 which had a similar cloud pattern (almost no outflow on the S/SW Quads). NHC says shear might decrease in 18 hr, we'll see how that turns out.

was a 70mph increase and 47mb drop in 24 hours not enough for you? Of course it didnt get to cat 5 today. But it wasnt because of shear. It was because of land. The eye was almost perfect at landfall and strengthening, I believe pressure bottomed out at 935mb right at landfall. Remember that this RI occurred under 20kt of shear...thats pretty crazy, and I see no reason it cant be a cat 5 tomorrow.

[Matt-hurricanewatcher]

Lets be truthful to our selfs about what is going on, this year is only slightly more favorable then 2007 north of 22 north. The caribbean is the most favorable part of the Atlantic for both this year and last. Above 20 north it is very unfavorable just look at Hanna and all other systems that tried to develop above it, so far this year. It is clear, if you disagree, then please do so.

We will likely get strong systems in the caribbean if they get in there, but this is not 2004, 2005. Those where "unnormal". The Gulf of Mexico is no where near as favorable as the caribbean...BUT and there is always a "but" this could pull a Lili like strengthing between the periods of strong shear(20+ knots is what I believe is strong shear), in which with in this period we could add another 10-15 knots onto the strength of this storm.

I would be amazed if this thing hit the Gulf coast as more then a low end cat3. I would be blown away; I don't think its going to happen. Rememer LILI as she strenthen, so will this weaken. It would also not blow me away to see this as a cat2 at landfall. Who's to argue that it is possible with possible 15-25 knots of shear. I don't think you went to argue it, because you could be proven wrong for doing so.

I think the governments judgement was a good one. You just can't take any chances, and they are doing a good job.

[Ivanhater]

HWRF has exactly 90w landfall

[alicia83]

I watched that station. Made me sick. No sooner than Nagin was off, one of their forecasters was playing down the storm. It's like they were focusing on the black line from earlier, and saying what damage could be expected and where as if it was carved in stone, and without giving any nod to the possibility of any slight deviation from that forecasted path.

Nagin said in so many words, any bets on the levies holding were off.

actually I have to jump in and make a correction on that. Been listening to that broadcast and need to clarify. He actually I think was trying to correct something so no one got the wrong idea. He was trying to say that the Mayor was 'right' that the "Footprint" of the storm is 900 miles across, but that the hurricane force winds were not 900 miles out but only 70 atm.

That forcaster at that particular point was correct in everything he said. I don't think he was downplaying at all at that point. He said he totally agreed with Nagin that people needed to evacuate.. this situation was very serious. At first impression I was thinking he was 'downplaying' things a bit too. But quickly realised what he was doing was just to clarify. Why? Cause well hurricane force winds won't be going "900 miles" out. And we don't want people further out from the track in other states in a panic.

And Nagin kept going on and on about the "900 mile footprint"... of course the Mayor is really trying to get people to evacuate.. and after the Katrina fiasco, I don't blame him one bit for hyping to be honest.

Granted that 900 mi. footprint was hype, but that forecaster was IMHO too casual about the situation, and almost seemed like he was enjoying taking Nagin down a notch. And for all the forecaster's outlining exactly what was going to happen in this or that parish, the track has now shifted a bit to the east. I don't know, the guy seemed a bit too light to be in the shoes he's in!

[wxmann_91]

With the highest heat content in the basin, Gustav did not reach Cat 5, this was b/c of the shear. No reason to see why a similar scenario will not pan out this time.

WRT to Hyperstorm's post, I'm not convinced this will weaken that rapidly, but I recall Lili back in 2002 which had a similar cloud pattern (almost no outflow on the S/SW Quads). NHC says shear might decrease in 18 hr, we'll see how that turns out.

was a 70mph increase and 47mb drop in 24 hours not enough for you? Of course it didnt get to cat 5 today. But it wasnt because of shear. It was because of land. The eye was almost perfect at landfall and strengthening, I believe pressure bottomed out at 935mb right at landfall. Remember that this RI occurred under 20kt of shear...thats pretty crazy, and I see no reason it cant be a cat 5 tomorrow.

There's a theoretical maximum a hurricane can get with only a single outflow channel, at least I read it somewhere. For a Cat 5 you not only need the SST's and OHC but you also need dual outflow channels. If it's a Cat 1 and it experiences this environment it can bomb to Cat 4 but has to plateau at that point. If it's a Cat 4 and it experiences this environment it can't go any higher up. Two different storms experiencing the same environment can do two totally different things.

Keep in mind that Cat 5's are suppose to be exceptionally rare. There's a reason for that.

[Texashawk]

An interesting sight I saw today... may mean something, may mean nothing..

I was stuck behind a caravan this afternoon of AT LEAST 50-75 empty charter buses (could have been more; passed them for almost 20 miles and never reached the front of the caravan) headed to Galveston. Given that charter buses to be available on short notice are VERY expensive, it made me wonder if maybe HGX knows something we don't, or whether they are just being overcautious.

Ot, it could just have been for some other freak thing entirely having nothing to do with evac, but man, it was a sight!

[cpdaman]

matt seriously .........fay had the best conditions over land on florida and just off the NE coast as well (good thing temps along the coast were in the mid70's in n-central east coast of florida or she would have likely gone to major) conditions were amazing

[Dean4Storms]

HWRF has exactly 90w landfall

WHAT????

[cheezyWXguy]

With the highest heat content in the basin, Gustav did not reach Cat 5, this was b/c of the shear. No reason to see why a similar scenario will not pan out this time.

WRT to Hyperstorm's post, I'm not convinced this will weaken that rapidly, but I recall Lili back in 2002 which had a similar cloud pattern (almost no outflow on the S/SW Quads). NHC says shear might decrease in 18 hr, we'll see how that turns out.

was a 70mph increase and 47mb drop in 24 hours not enough for you? Of course it didnt get to cat 5 today. But it wasnt because of shear. It was because of land. The eye was almost perfect at landfall and strengthening, I believe pressure bottomed out at 935mb right at landfall. Remember that this RI occurred under 20kt of shear...thats pretty crazy, and I see no reason it cant be a cat 5 tomorrow.

There's a theoretical maximum a hurricane can get with only a single outflow channel, at least I read it somewhere. For a Cat 5 you not only need the SST's and OHC but you also need dual outflow channels. If it's a Cat 1 and it experiences this environment it can bomb to Cat 4 but has to plateau at that point. If it's a Cat 4 and it experiences this environment it can't go any higher up. Two different storms experiencing the same environment can do two totally different things.

Keep in mind that Cat 5's are suppose to be exceptionally rare. There's a reason for that.

I know and I believe they are rare. But this was/is going to be one of them. This was still strengthening at landfall. Im like 80% sure that if this had another 6 hours of time over water before cuba, that it wouldve hit at 160. And Im pretty sure it did have 2 outflow channels. Nonetheless, its not important now. It didnt get there, though I do believe it would have had there been no land interaction.

Now over the next 24 hours I see good chance of cat5. This is because this storm has been organizing since immidiately off the coast, along with slowly decreasing shear over the next day. We just need to see.

[vacanechaser]

This system will HAVE to accelerate its forward speed if it's going to make landfall as a Category 4 as forecast. Right now, upper-level winds on the southern side are starting to approach the system and will impede this system maintaining Category 4 intensity for much longer. You can see on water vapor loops the upper-level shield moving northward VERY rapidly toward the system. That will be GREAT news if I wake up tomorrow morning to a Category 3 or LOWER. That is VERY possible with the way the upper-level winds are impinging heavily on the southern side.

This system is reminding me of the structure/side of Dennis as it was making landfall in 2004. IMO, this is the kind of system we will see in Louisiana - Category 2 or minimal 3 with a similar size to Dennis. Still, something dangerous, but not catastrophic/widespread as some make it seem to be.

In any case, PREPARE for the WORST, but I'm seeing some good things tonight. God Bless all in its path...

I guess the perfect circular CDO and cold cloudtops show its going to weaken significantly overnight.

I can sense your sarcasm.

When a VERY powerful hurricane loses its eye like this system did in such a short amount of time and the southern edge is being impeded by southerly shear which is throwing dry air into it, you WILL see a VERY sharp pressure rise. We saw a very similar situation in 2002 with Hurricane Lili.

I will not be at all surprised if the pressure in this system is now in the 960s and going higher...

no way... and lili, went over the same area that isadore went over just a week or so earlier.. the water was churned up and cooler along the path... lets put all the peices together before we get carried away... no way the pressure is up that high... the reason the filled was due to land interaction... looking at the convection, it is already coming back..



Jesse V. Bass III
http://www.vastormphoto.com
Hurricane Intercept Research Team

[PTPatrick]

Newest NOGAPS, GFS AND CMC are all GRAND ISLE, LaFourche parrish landfalls if you ask me...although I cant tell exactly from the resolution. They all also take from from Grand isle toward Thibideaux and then toward Lafayette.

[Matt-hurricanewatcher]

matt seriously .........fay had the best conditions over land on florida and just off the NE coast as well (good thing temps along the coast were in the mid70's in n-central east coast of florida or she would have likely gone to major) conditions were amazing

If this had the same for it over the gulf right now, I would be calling for this to go to a cat5 very fast, but it don't.

[vbhoutex]

An interesting sight I saw today... may mean something, may mean nothing..

I was stuck behind a caravan this afternoon of AT LEAST 50-75 empty charter buses (could have been more; passed them for almost 20 miles and never reached the front of the caravan) headed to Galveston. Given that charter buses to be available on short notice are VERY expensive, it made me wonder if maybe HGX knows something we don't, or whether they are just being overcautious.

Ot, it could just have been for some other freak thing entirely having nothing to do with evac, but man, it was a sight!

It was the State of TX staging buses for possible evacuations IF there is a need.

[ConvergenceZone]

stinking satelite eclipse

i think everyone will be awake till the eclipse ends at 215 edt and the quikest updating sites have shots out by 230 am.

i am thinking a thin black circle around her on infared.

cpdaman, thanx for reminding me about that. I was wondering why I kept hitting "refresh" and the satellite picture wasn't updating....