That eye clearing out and eyewall building fast

[Anonymous]

http://www.srh.noaa.gov/radar/loop/DS.p ... kbyx.shtml

Dennis certianly appears to be strengthening as it drifts away from Northwestern Cuba. The latest radar images show a better defined eyewall, and the inside of the eye is beginning to clear out. In my opinion, I fear Hurricane Dennis may rapidly deepen this morning to a serious major hurricane.

[gkrangers]

Check the new VORTEX....

[rtd2]

Glad to see you Here this late Hr. When will you Do another F'cast? Do you think Dennis coming off Closer to Havanah has Future L/F Implications?

http://www.meteo.psu.edu/~gadomski/SAT_ATL/anim8ir.html

http://www.meteo.psu.edu/~gadomski/SAT_ATL/anim8wv.html

[Sanibel]

Dennis's core structure was excellent all the way over Cuba. When the energy stored in that deep convection in his SE band transfers - BOOM...

[Anonymous]

Glad to see you Here this late Hr. When will you Do another F'cast? Do you think Dennis coming off Closer to Havanah has Future L/F Implications?

http://www.meteo.psu.edu/~gadomski/SAT_ATL/anim8ir.html

http://www.meteo.psu.edu/~gadomski/SAT_ATL/anim8wv.html

Tomorrow morning or afternoon.

[Matt-hurricanewatcher]

The vortex shows that it has a well defined eye which is closed. But the news is it only has 69 knots. In which case Arlene had 75 knots flight level. In this case if true this storm might be only 50 to 55 mph. Don't can't believe it.

[rtd2]

Dennis's core structure was excellent all the way over Cuba. When the energy stored in that deep convection in his SE band transfers - BOOM...

Sanibel and Others ...we know Major canes Vertical stack and Unwind as they come apart on land and Sling Clusters of storms Out bound...which dennis has Done somewhat but with him Getting his act together again do you think we will see an Overall LARGER storm-wind field or Tight and compact as before? A see Alot of Outter band activity that makes his Presence Much larger than before

[baitism]

Even if it has weakened that much it easily has enough time to gain back what it lost.

[Normandy]

The winds may be low because of no convection....it had a core, but with no heavy convection.....just a guess.

[Sanibel]

TWC last reported 110mph...

[Anonymous]

The vortex shows that it has a well defined eye which is closed. But the news is it only has 69 knots. In which case Arlene had 75 knots flight level. In this case if true this storm might be only 50 to 55 mph. Don't can't believe it.

LOL Its a powerful hurricane

[gkrangers]

NHC is going to have to lower the winds, unless they got recon with higher numbers.

Also...the temp is only 54 degrees at 138 feet inside the eye!! Doesn't that strike you as very cold?

[Sanibel]

Dennis likes the Gulf Stream. Beefing up and bursting cold tops in NE quadrant...

[Matt-hurricanewatcher]

The radar shows that it now is developing a well defined eye. The eye wall is forming reds. This looks like its getting oreganized fast.

[clfenwi]

NHC is going to have to lower the winds, unless they got recon with higher numbers.

Also...the temp is only 54 degrees at 138 feet inside the eye!! Doesn't that strike you as very cold?

I've no idea how, but something got garbled on the decode, here is the raw:

000

URNT12 KNHC 090555
VORTEX DATA MESSAGE
A. 09/05:26:30Z
B. 23 DEG 17 MIN N
82 DEG 23 MIN W
C. 700 MB 2856 M
D. NA
E. NA
F. 142 DEG 69 KT
G. 051 DEG 28 NM
H. 974 MB
I. 9 C/ 3042 M
J. 12 C/ 3042 M
K. 12 C/ NA
L. CLOSED WALL
M. C12
N. 12345/7
O. .02/1 NM
P. AF300 1104A DENNIS OB 01
MAX FL WIND 69 KTS NE QUAD 05:18:10Z
LAST REPORT.

That temps was at 3042 meters // 9980 feet.

[soonertwister]

I was quite concerned for Key West until a few hours ago, when Dennis strarted turning sharply westerly. The 6 hour trend before that had been much more northerly, but once Dennis was on-shore in Cuba and weakening, he rotated westward as though on a tether.

So just when it looked like he was going to run right over Hanana I caught some shuteye, and in the ensuing period he turned back toward the right, and it appears that most of the Havana area avoided the worst of his weakening winds. While Dennis still has good structure, I'm noting that the air to the west and northwest has become quite dry. It now appears, after earlier concerns for Key West, that he will pass no closer than perhaps 75 miles west of Key West, so they won't be getting hurricane force winds there.

Perhaps more importantly, with his weakening over land and deviation to the left, the storm surge probably won't be terribly great, maybe as small as 3-5 feet above normal until the storm passes north of Key West. It may be that the worst surge seen there will actually be after Dennis is north and west of Key West, but strengthening.

But with abundant dry air to the left of the storm, I'm not convinced now that Dennis will strengthen all that much before landfall. The more he strengthens in the southeastern Gulf, the more likely that he will entrain dry air, which will kill the strengthening of this storm.

I'm still somewhat in favor of this storm turning northward, although he's currently trending toward New Orleans. And I think that the ultimate landfall will be toward the right of guidance, but not outside of the cone. My best guess would be a central panhandle landfall, possibly as only a category 2 hurricane, or even weaker. I don't think we will see the monster that we saw before unless Dennis turns to the north northeast, and I don't see that happening.

Just like so many hurricanes before, time and conditions have provided a cap on his redevelopment into a major hurricane. I wouldn't rule out strengthening into a category 3, even a strong category 3, but as Dennis gets stronger and the convection becomes more widespread, the likelihood increases dramatically that he will take that big gulp of dry air that will limit development.

I think that now I'll be surprised if he comes ashore with much more than 115 mph winds, but I won't be too surprised if he's somewhat stronger, particularly if he turns more to the right. But I think the chances of a major hurricane striking the New Orleans area are just about nil. If landfall occurs somewhere north of Tampa Bay, we could see a strong category 3 at a maximum, in my opinion.

But I think that Dennis will never redevelop into a catastrophic hurricane in the Gulf. There just aren't enough factors present there for me to think that will happen.

[wayoutfront]

Conditions at 42003 as of
(2:50 am CDT)
0750 GMT on 07/09/2005:

Wind Direction (WDIR): ENE ( 60 deg true )
Wind Speed (WSPD): 19.4 kts
Wind Gust (GST): 23.3 kts
Wave Height (WVHT): 4.9 ft
Dominant Wave Period (DPD): 5 sec
Average Period (APD): 4.2 sec
Mean Wave Direction (MWDIR): E ( 79 deg true )
Atmospheric Pressure (PRES): 29.78 in
Pressure Tendency (PTDY): -0.05 in ( Falling )
Air Temperature (ATMP): 82.2 °F
Water Temperature (WTMP): 84.0 °F
Dew Point (DEWP): 77.2 °F
Heat Index (HEAT): 90.7 °F

[birdwomn]

But I think that Dennis will never redevelop into a catastrophic hurricane in the Gulf. There just aren't enough factors present there for me to think that will happen.

While I enjoyed your entire analysis, I really liked this part!
That is what I have been hoping for all along, I just wasn't sure it would be possible until Dennis stayed over Cuba so long. Of course, I realize that we still have several hours to wait and see what this storm will do in terms of deepening convection. Time will tell.

[mobilebay]

I was quite concerned for Key West until a few hours ago, when Dennis strarted turning sharply westerly. The 6 hour trend before that had been much more northerly, but once Dennis was on-shore in Cuba and weakening, he rotated westward as though on a tether.

So just when it looked like he was going to run right over Hanana I caught some shuteye, and in the ensuing period he turned back toward the right, and it appears that most of the Havana area avoided the worst of his weakening winds. While Dennis still has good structure, I'm noting that the air to the west and northwest has become quite dry. It now appears, after earlier concerns for Key West, that he will pass no closer than perhaps 75 miles west of Key West, so they won't be getting hurricane force winds there.

Perhaps more importantly, with his weakening over land and deviation to the left, the storm surge probably won't be terribly great, maybe as small as 3-5 feet above normal until the storm passes north of Key West. It may be that the worst surge seen there will actually be after Dennis is north and west of Key West, but strengthening.

But with abundant dry air to the left of the storm, I'm not convinced now that Dennis will strengthen all that much before landfall. The more he strengthens in the southeastern Gulf, the more likely that he will entrain dry air, which will kill the strengthening of this storm.

I'm still somewhat in favor of this storm turning northward, although he's currently trending toward New Orleans. And I think that the ultimate landfall will be toward the right of guidance, but not outside of the cone. My best guess would be a central panhandle landfall, possibly as only a category 2 hurricane, or even weaker. I don't think we will see the monster that we saw before unless Dennis turns to the north northeast, and I don't see that happening.

Just like so many hurricanes before, time and conditions have provided a cap on his redevelopment into a major hurricane. I wouldn't rule out strengthening into a category 3, even a strong category 3, but as Dennis gets stronger and the convection becomes more widespread, the likelihood increases dramatically that he will take that big gulp of dry air that will limit development.

I think that now I'll be surprised if he comes ashore with much more than 115 mph winds, but I won't be too surprised if he's somewhat stronger, particularly if he turns more to the right. But I think the chances of a major hurricane striking the New Orleans area are just about nil. If landfall occurs somewhere north of Tampa Bay, we could see a strong category 3 at a maximum, in my opinion.

But I think that Dennis will never redevelop into a catastrophic hurricane in the Gulf. There just aren't enough factors present there for me to think that will happen.

I couldn't disagree more. In fact I disagree with that entire forecast. Thats just my opinion though.
Here is the reasoning... The Cyclone is embedded within very moist air that is moving with the Cyclone. Also the cloud tops are cooling around the EYE which is very Visible with the moist air on this Water Vapor Loop.
http://www.ssd.noaa.gov/PS/TROP/DATA/RT ... -loop.html

Conditions are pretty good right now for some rapid strengthening. Warm SST's in the South and Central Gom. Basically no wind shear. Again, this just my opinion. No offense.

[Derek Ortt]

matt,

a conversion factor of 90 percent is used at 700mb. 80 percent is used at 850, which is the level they flew arlene