ATL: KAREN - Remnants - Discussion

[Hurricaneman]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Would there be any real lasting consequence between those two potential outcomes?

It would have trouble strengthening until it’s one unified vortex due to sharing of energy between the 2 vortices

[tropicwatch]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

They are flying back through the suspect area instead of heading east like they did last pass.

[aperson]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

They are flying back through the suspect area instead of heading east like they did last pass.

Looks like the new circulation is becoming better defined according to the wind field as well

[AJC3]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Would there be any real lasting consequence between those two potential outcomes?

Any westward relocation increases the chance of Karen getting trapped. Assuming that does happen, another aspect of the model guidance that I think people will start talking about is the fact that the global models are pretty unanimous in showing some hostile upper tropospheric shear from an upper level trough developing from the Bahamas to the Florida east coast starting in about 4 days and lasting into next week.

[tropicwatch]

One of the things I have noticed is they that have had trouble finding true easterly winds. Plenty of westerlies but not many easterlies. That has changed, finding pressure drops and easterly winds around the new area.

[HDGator]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Spot on with the analysis. Without a strong center of circulation it's hard to get a coherent track but the NNE movement is on track.
The circulation is still elongated NNE and the track may depend on how it works out in organization.

[Stormi]

Oddly quiet in here considering the circumstances. Tropical burn-out perhaps ? I'd like to see the Google Adsense Bot weigh in on the discussion

Literally thinking the same

[tropicwatch]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Would there be any real lasting consequence between those two potential outcomes?

Any westward relocation increases the chance of Karen getting trapped. Assuming that does happen, another aspect of the model guidance that I think people will start talking about is the fact that the global models are pretty unanimous in showing some hostile upper tropospheric shear from an upper level trough developing from the Bahamas to the Florida east coast starting in about 4 days and lasting into next week.

I noticed that there already is a ull to Karen's northwest tonight.

[Hurricaneman]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Would there be any real lasting consequence between those two potential outcomes?

Any westward relocation increases the chance of Karen getting trapped. Assuming that does happen, another aspect of the model guidance that I think people will start talking about is the fact that the global models are pretty unanimous in showing some hostile upper tropospheric shear from an upper level trough developing from the Bahamas to the Florida east coast starting in about 4 days and lasting into next week.

The thing is shear forecast beyond 3 days can be off and That’s the thing that needs to be watched as if the shear is different or there’s little to no shear instead things could get interesting

[Stormi]

It's pretty clear that a second LLC has been trying to form north of central PR. If that one doesn't take over as a new center per se, then what I thnk will happen is that these two vort centers will show a loose binary motion about a central point between them, and then congeal somewhere in between, while the whole mess moves on a heading between N and NNE. This was my thinking when I mentioned last evening that the next few center fixes would go north and possibly a little west of due north.

Would there be any real lasting consequence between those two potential outcomes?

Any westward relocation increases the chance of Karen getting trapped. Assuming that does happen, another aspect of the model guidance that I think people will start talking about is the fact that the global models are pretty unanimous in showing some hostile upper tropospheric shear from an upper level trough developing from the Bahamas to the Florida east coast starting in about 4 days and lasting into next week.

I agree. It appears that Karen has found a bit of a sweet-spot shear-wise, but will definitely face challenges in that regard soon. How well the system can organize before moving into that area of less-favorable conditions is what I'm curious to see.

[AJC3]

Would there be any real lasting consequence between those two potential outcomes?

Any westward relocation increases the chance of Karen getting trapped. Assuming that does happen, another aspect of the model guidance that I think people will start talking about is the fact that the global models are pretty unanimous in showing some hostile upper tropospheric shear from an upper level trough developing from the Bahamas to the Florida east coast starting in about 4 days and lasting into next week.

I noticed that there already is a ull to Karen's northeast tonight.

I think you meant to its NW. That ULL is forecast to drift south and then west over the Bahamas through about early Friday, before lifting N-NE away from the SE seaboard ahead of the developing sharp UL trough that I mentioned.

[tropicwatch]

They are not calling the area north of San Juan the center yet but there location is a little west of the most recent center forecast track.

[HDGator]

Convection circulation on radar seems to be coalescing west of the track guidance tonight North of Puerto Rico.

[aperson]

However, MSLP is dropping heftily near the old LLC. The last barb here was at 1002 MSLP

[LarryWx]

They are not calling the area north of San Juan the center yet but there location is a little west of the most recent center forecast track.

I’d call that location more than just a little west of the most recent NHC track. It looks like a good 75 miles or so at least! It could even be over 100 miles. That is enough to potentially have big implications as far as how model runs play out. As was mentioned, that would almost certainly mean the furthest east she gets at the anticipated pause would be 1-2+ degrees further west, which alone could increase the CONUS threat. Then there’s the question of what that would likely mean in terms of what latitude she’d likely travel W or WSW along. That depends on whether a further west starting point would mean slower or faster on its anticipated move NNE the next 60 or so hours before the expected pause. Any guesses?

[tropicwatch]

They are not calling the area north of San Juan the center yet but there location is a little west of the most recent center forecast track.

I’d call that location more than just a little west of the most recent NHC track. It looks like a good 75 miles or so at least! It could even be over 100 miles. That is enough to potentially have big implications as far as how model runs play out. As was mentioned, that would almost certainly mean the furthest east she gets at the anticipated pause would be 1-2+ degrees further west, which alone could increase the CONUS threat. Then there’s the question of what that would likely mean in terms of what latitude she’d likely travel W or WSW along. That depends on whether a further west starting point would mean slower or faster on its anticipated move NNE the next 60 or so hours before the expected pause. Any guesses?

I was referring to the location of the latest VDM which puts it just west of center track. Not the area of where the center might be reforming.

[HDGator]

The rains continue to hammer Puerto RIco now. I pray you guys are safe because it looks to go on through the night.

[Stormi]

They are not calling the area north of San Juan the center yet but there location is a little west of the most recent center forecast track.

I’d call that location more than just a little west of the most recent NHC track. It looks like a good 75 miles or so at least! It could even be over 100 miles. That is enough to potentially have big implications as far as how model runs play out. As was mentioned, that would almost certainly mean the furthest east she gets at the anticipated pause would be 1-2+ degrees further west, which alone could increase the CONUS threat. Then there’s the question of what that would likely mean in terms of what latitude she’d likely travel W or WSW along. That depends on whether a further west starting point would mean slower or faster on its anticipated move NNE the next 60 or so hours before the expected pause. Any guesses?

I was watching Mark S. talk about this earlier tonight. By his calculations, the average differential for COC would be around 100 miles. I would guess West possibly a bit further South than originally anticipated if the ridge holds. Timing is difficult though, especially with what was stated earlier about dueling vortices and their impacts on intensification - on top a potential stall/turn/meandering & everything else! Fascinating really. For me at least, this has been by far the most interesting system to track this season. Imagine what a forecasting differential of 100 miles would've meant for Dorian!

[LarryWx]

Well, folks, in looking at the latest satellite loops along with lightning, one can clearly see thunderstorms have blossomed over the old LLC near 20N, 65W, which is about where the NHC had her at 2 AM. Based on this, I'm now thinking the old LLC will likely prevail. If so, the 0Z Euro's hour 6 location is about right on the money thus making it more useful than it would otherwise be,

[sma10]

Well, folks, in looking at the latest satellite loops along with lightning, one can clearly see thunderstorms have blossomed over the old LLC near 20N, 65W, which is about where the NHC had her at 2 AM. Based on this, I'm now thinking the old LLC will likely prevail. If so, the 0Z Euro's hour 6 location is about right on the money thus making it more useful than it would otherwise be,

Agreed. And even though extremely weak, Euro still takes her pretty much all the way back west as a potential nuisance