ATL : TROPICAL DEPRESSION IDA

[littlevince]

[artist]

that mission wsa only just over an hour in the storm. I don't think they have ever been that short other than when they had trouble.

[Aric Dunn]

The center is being found fine by recon - there are no issues with that. They may be missing it by a mile or two, not by 60-100 miles - we're talking professionals inside the storm here, and if they find a circulation with a well-defined ~991mb low pressure associated with it, I think THAT is the storm, not a pseudo-swirl offset to the east of the deep convection, like due to some subsidence from the intense thunderstorms over the actual center.

The issue is not the little warm spot on satellite.. its with the recon data.. there is probably 2 vorts in there now. the old one with the pressure of that 988 and the one they seemed to have just did a drop in with 991. thes types of reading are very normal for multiple vorts or a center relocation..

Not really...typically reforming centers happen in systems with poorly organized convection (i.e. sporadic, randomly forming deep-layered storms) and weak circulation centers to begin with. Hence, it's rare to see center reformations in any system with central pressures lower than 1000hPa, and that's being generous. Center reformations certainly will not occur in a storm nearing hurricane strength with organized convection and a very strong low level circulation.

yes but we have a semi decoupled system and watch the convection it is pretty sporadic especially the last couple hours. also you can have a 70 mph that has no inner core.

are two separate lobes of convection.. which can lead to multiple vorts...

[KWT]

Yeah its not reforming a circulation when you've got pressure that low, it could be an eddy I suppose but its certainly not the center thats for sure.

[brunota2003]

Granted, that is a really long way to fly from Keesler.

[Blown Away]

Aric, you have said you thought the center had reformed to a new location, what are the lat/longs for that location?

[Aric Dunn]

Yeah its not reforming a circulation when you've got pressure that low, it could be an eddy I suppose but its certainly not the center thats for sure.

that little warm spot is not what im talking about...
it was in the recon data .. but oh well will see what the nhc says.. was there ever vortex for that last pass... dont think there was ..

[Evil Jeremy]

I wonder if tonight's flight is also flying out of Keelser. The Homestead base is much closer to Ida.

[brunota2003]

But, does the AF currently have a plane at Homestead?

[Aric Dunn]

Aric, you have said you thought the center had reformed to a new location, what are the lat/longs for that location?

Not any great distance or anything.. just typical of a decoupled system its continually trying to stay with the mid level circ.. in the recon data it was off by a 5 miles or so ...

[Normandy]

From what I understood, they fixed a center during the first pass (990 mbs), then they fixed it again just NNW of the first (991) indicating a NNW movement. Where is the other center Aric?

[KWT]

No I don't think there was a vortex which is a very good point Aric, who knows I'll wait to see what the NHC say.

[cycloneye]

But, does the AF currently have a plane at Homestead?

Good question.Is much more closer to not use more fuel.

[Aric Dunn]

From what I understood, they fixed a center during the first pass (990 mbs), then they fixed it again just NNW of the first (991) indicating a NNW movement. Where is the other center Aric?

the lowest pressure was 988 but with 20 kts of wind .. the lowest winds corresponded to a pressure of 991mb which is what you often see with reforming ... the pressure gradient opens slightly as this that process happens .. thats all im saying..

[Aric Dunn]

hey speak of the devil there is the vortex message..

MAX FL WIND 67 KT SW QUAD 16:41:10Z
MAX FL TEMP 25 C 148 / 19 NM FROM FL CNTR
SPIRAL BAND PATTERN
ACTUAL CENTER APPROX 4NM SE

[brunota2003]

Here is the VDM from the last pass:

000
URNT12 KNHC 071919
VORTEX DATA MESSAGE AL112009
A. 07/18:32:20Z
B. 18 deg 52 min N
084 deg 10 min W
C. 850 mb 1349 m
D. 48 kt
E. 145 deg 29 nm
F. 238 deg 63 kt
G. 148 deg 19 nm
H. 991 mb
I. 17 C / 1526 m
J. 20 C / 1520 m
K. 17 C / NA
L. NA
M. NA
N. 12345 / 8
O. 0.02 / 4 nm
P. AF306 0211A IDA OB 10
MAX FL WIND 67 KT SW QUAD 16:41:10Z
MAX FL TEMP 25 C 148 / 19 NM FROM FL CNTR
SPIRAL BAND PATTERN
ACTUAL CENTER APPROX 4NM SE

[Normandy]

Nah I get what your saying, but perhaps the storm is weakening which explains the second fix being 991 as opposed to the first 988 with 29kts of wind. The two fixes make sense Re: movement of the storm. Maybe Im just not understanding.

[cycloneye]

Any pro met wants to chim in to the discussion about the center and the plane fixes?

[WindRunner]

yes but we have a semi decoupled system and watch the convection it is pretty sporadic especially the last couple hours. also you can have a 70 mph that has no inner core.

If you're arguing for semi-decoupled, then do that, I can agree with you there. Mild wind shear will support a flight-level center that doesn't align with the surface center, and that's what we have here... EDIT: now supported by the VDM, too

[Aric Dunn]

hey speak of the devil there is the vortex message..

MAX FL WIND 67 KT SW QUAD 16:41:10Z
MAX FL TEMP 25 C 148 / 19 NM FROM FL CNTR
SPIRAL BAND PATTERN
ACTUAL CENTER APPROX 4NM SE

like i said about 5 miles.