ATL: HERMINE - Post-Tropical - Discussion

[NJWxHurricane]

https://twitter.com/DanLeonard_wx/statu ... wsrc%5Etfw

[NJWxHurricane]

GFS has a stronger storm in the Mid-Atlantic, then in the gulf.

[chaser1]

One factor: The disorganized nature of this system. Really wondering (as I said last night) if that might play a role in making it more difficult for the storm to be picked up by the approaching trough. In other words making this mess of a depression less susceptible to upper atmospheric influences (like the trough).

Its true that a very shallow system might miss and not be picked up by mid level steering, and its motioni be influenced soley by surface trades. This is not always the case though.

In some cases where a deep enough trough may cause a very "deep" flow in advance or as a cause of it. Imagine a river where the lower currents are flowing toward downstream, but where the currents near the surface or top few inches of that body of water are also flowing in that same direction in part, due to the same coincedental direction that the wind might be blowing. Often times a deep layer flow implies that the flow at the surface, mid, and upper levels are more or less in tandum. Given a certain level of recent model consistancy lately, NHC seems confident enough to believe that the trough along the Atlantic seaboard will be deep enought to cause a fairly deep flow at the base of, and ahead of this digging trough feature.

[cycloneye]

 https://twitter.com/StuOstro/status/770661121808338946

[whatacane]

One factor: The disorganized nature of this system. Really wondering (as I said last night) if that might play a role in making it more difficult for the storm to be picked up by the approaching trough. In other words making this mess of a depression less susceptible to upper atmospheric influences (like the trough).

Its true that a very shallow system might miss and not be picked up by mid level steering, and its motioni be influenced soley by surface trades. This is not always the case though.

In some cases where a deep enough trough may cause a very "deep" flow in advance or as a cause of it. Imagine a river where the lower currents are flowing toward downstream, but where the currents near the surface or top few inches of that body of water are also flowing in that same direction in part, due to the same coincedental direction that the wind might be blowing. Often times a deep layer flow implies that the flow at the surface, mid, and upper levels are more or less in tandum. Given a certain level of recent model consistancy lately, NHC seems confident enough to believe that the trough along the Atlantic seaboard will be deep enought to cause a fairly deep flow at the base of, and ahead of this digging trough feature.

Very well put! thanks.

[GCANE]

First time I have seen a CAPE of 4000 near this.
Its just west of the convection at about 23.2N 88.5W.
I am not sure what is going on with the convection along 84W.

what is that?

I am going to treat that area like an ex-wife and ignore it.
Getting some really nice outflow in all directions now.

http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

[benh316]

GFS has a stronger storm in the Mid-Atlantic, then in the gulf.

I just don't understand how anyone can believe this will strengthen without a true center of circulation. I am not sure if anyone has proved the existence of multiple vortices in this system, but I do not believe wind shear has been the only cause for its lack of solidarity. The conditions are very reasonable for strengthening and yet the convection continues to show inconsistency.

Maybe I am being skeptical at this point, but until I see this system begin rotating properly - I am not holding my breath

[whatacane]

First time I have seen a CAPE of 4000 near this.
Its just west of the convection at about 23.2N 88.5W.
I am not sure what is going on with the convection along 84W.

what is that?

I am going to treat that area like an ex-wife and ignore it.
Getting some really nice outflow in all directions now.

http://tropic.ssec.wisc.edu/real-time/m ... 2hr_03.gif

[tolakram]

ULL looks just to the west of Nine.

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=25&lon=-85&info=wv&zoom=4&width=1400&height=800&quality=90&type=Animation&palette=wv2.pal&numframes=30&mapcolor=black

[chaser1]

Well while there's some data suggesting stronger winds I do not think these winds will remain sustained if we're about to go through yet another downturn in convective activity or for those colder tops to simply be sheared away again. At minimum, were continueing to see some level of undercutting shear which sure looks to me to be causing the LLC to be exposed to the north and on the edge of some deep (but small area of) convection. Based on this alone, I do not see NHC upgrading without actual manned recon determining these winds have been maintained and perhaps some evidence of minimal pressure falls. Might well still have a TD at 5:00pm but with the addition of obligitory T.S. Watches for those areas most prone for risk of T.S. conditions.

[StormHunter72]

Learned a lot here lately. Most important for future storms who is doubting the pros and -removed-. All and all great site. Once you listen to the experienced members.

[tolakram]

30 frame visible

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=25&lon=-87&info=vis&zoom=1&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=30&mapcolor=black

Zoom 2

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=25&lon=-87&info=vis&zoom=2&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=30&mapcolor=black

[NJWxHurricane]

GFS has a stronger storm in the Mid-Atlantic, then in the gulf.

I just don't understand how anyone can believe this will strengthen without a true center of circulation. I am not sure if anyone has proved the existence of multiple vortices in this system, but I do not believe wind shear has been the only cause for its lack of solidarity. The conditions are very reasonable for strengthening and yet the convection continues to show inconsistency.

Maybe I am being skeptical at this point, but until I see this system begin rotating properly - I am not holding my breath

Agreed

[tropicwatch]

ULL looks just to the west of Nine.

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=25&lon=-85&info=wv&zoom=4&width=1400&height=800&quality=90&type=Animation&palette=wv2.pal&numframes=30&mapcolor=black

looks what?

[hurricanefloyd5]

When will td9 become tropical storm hermine Or Ian?

[psyclone]

Learned a lot here lately. Most important for future storms who is doubting the pros and -removed-. All and all great site. Once you listen to the experienced members.

It does not take long to figure out who to listen to. Like any tool you just need to learn how to use it.

[SEASON_CANCELED]

where is the trough at this that sweeps it up???

[tolakram]

The models have this rather disorganized for at least another day, only really getting its act together in 36 hours or so. The latest GFS shoes the center relocating to the northeast and then organizing between 48 and 66 (landfall). I would not be surprised if this looks a lot worse before it improves.

[NDG]

Which circulation are you looking at?

Looking at vis loop half of the LLC circulation is now exposed.

The main LLC near 24N &87W, the MLC is still to the south of it where most of the convection is.

[GCANE]

ADT is picking up on it

http://tropic.ssec.wisc.edu/real-time/adt/09LP.GIF