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Remnants of Emily Part II: 295 Miles SSE Of Cape Hatteras, NC


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I'm watching the visible satellite imagery, and it seems to me that part of the problem is that, while overall shear from the surface to the tropopause isn't that great (it's there, but relatively weak), there are multiple layers of shear in there. It seems to me as if there is moderate northerly flow at the mid-levels, and then southerly flow at the upper-levels. That would make relative shear between the mid- and upper-levels quite high.

I say this because it looks like new convection starts off with the tops being blown southward, but the tops of the tallest convection (highest cirrus) are being blown northward. Am I seeing this correctly?

http://wwwghcc.msfc....i-bin/post-goes

Yep... this the same problem that CU Met alluded to the past couple of days. Northwesterly 300mb flow is undercutting the more favorable 200mb flow.

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Yep... this the same problem that CU Met alluded to the past couple of days. Northwesterly 300mb flow is undercutting the more favorable 200mb flow.

Ya, I had just remembered your sounding after I posted that. 50kts of shear between 300mb and 200mb is not a good thing.

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Well that's just mean... all I wanted was a radar! ;)

I was slightly wrong. It's a transitive verb, so it needs an object. "No molesta(s) [x]" means do not bother/disturb [x]. Idonno why the "me" comes before "molesta" in the phrase "no me molesta", which means don't bother me. Jorge can correct me if I'm wrong. :arrowhead:

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Chilled.

I think Emily has put out a giant arc cloud that is in the shape of a feeder band, if that makes any sense.

I think what you are seeing is dry air and moist air entangling and creating a weird yin-yang pattern. The "arc" cloud I believe you are referring to is a visual artifact of that, not anything important.

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I would kind of like to watch a recently-exposed naked swirl (especially from a stronger system) as it passed overhead. Watching the tiny popcorn cumulus quickly swirl around the center with nothing obstructing the view would be kinda cool.

I've been in a naked swirl before... trust me, it isn't all that exciting. You're lucky if you get in the convection that's sheared away from to get a slightly-stronger-than-a-typical-Gulf-summer-thunderstorm thunderstorm. :)

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I've been in a naked swirl before... trust me, it isn't all that exciting. You're lucky if you get in the convection that's sheared away from to get a slightly-stronger-than-a-typical-Gulf-summer-thunderstorm thunderstorm. :)

Oh, it's not the excitement... believe me. I would want to avoid thunderstorms! I just think it would be an eerie/weird sight to see harmless clouds swirling menacingly with only some moderate winds and partly sunny skies. :P

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Oh, it's not the excitement... believe me. I would want to avoid thunderstorms! I just think it would be an eerie/weird sight to see harmless clouds swirling menacingly with only some moderate winds and partly sunny skies. :P

That part is interesting, I suppose... but I get more excitement from seeing a line of sea breeze front thunderstorms in the distance... lol. They are actually pretty similar (maybe a few more fastish moving low clouds in the naked swirl, of course)

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That part is interesting, I suppose... but I get more excitement from seeing a line of sea breeze front thunderstorms in the distance... lol. They are actually pretty similar (maybe a few more fastish moving low clouds in the naked swirl, of course)

Haha, fair enough.

As for Emily, unless the latest satellite image from 18:15 is faulty, it looks like the "new" burst of convection near the center is already falling apart. How are you going to keep convection alive when the top half is being sheared in two different directions?

Stuff is still firing northeast of the center, though.

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Haha, fair enough.

As for emily, unless the latest satellite image from 18:15 is faulty, it looks like the "new" burst of convection near the center is already falling apart. How are you going to keep convection alive when the top half is being sheared in two different directions?

Stuff is still firing northeast of the center, though.

This is also fairly well timed with the greatest amount of downsloping dry flow coming off the peaks.

The stuff firing NE of the center is likely part of what Phil was saying... frictional convergence on the windward side of the island.

For the dying convection, it is most likely a combination of shear and lee flow being wrapped, IMO.

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The longer the circulation remains weak and surface based, the further west it's going to go, closer to the BAM-shallow. GFS, EC and especially the UK came in much further west. Convection is beginning to fire again, but I think it's already too late for the east track.

I'm willing to bet this thing goes south of Miami, maybe over the Keys, and makes landfall in the panhandle as a Tropical Storm. Don't really have time to draw a map right now but that's my forecast! :popcorn:

Ok, I gave in after all...

I'd also like to add to my above reasoning that progressive dry air entrainment from the north, as well as much higher shear north of the system than south of it, may allow for the center of circulation to redevelop to the south multiple times between now and Hispanola, further enhancing the southward track.

post-378-0-25249600-1312227788.jpg

Looks like my forecast from Monday of going south and west of NHC has held up reasonably so far. This is due to a number of factors, including but not limited to: the lack of organization of the system, allowing the low-level circulation to be advected by the low-level easterlies, pulses of convection as the shear periodically increases then relaxes, allowing for center relocation to the south, and a slightly stronger ridge than forecast (except by UKMET). I no longer expect a track quite that far west near the end of my forecast, but I continue to think that Emily will stay left of the NHC forecast.

The intensity forecast has been reasonable so far as well. Bare in mind that I made this forecast before recon Wed found a TS, so I was initially expecting a TD for the first few days. I am still anticipating a weakening to TD by this time tomorrow. Although Emily appears to be ingesting less dry air than before, the combination of a 300 mb northerly jet and land interaction will cause weakening. However, shear should abate north of Cuba, so if deep convection can re-develop coincident with the low-level vortex post Cuba, I would expect re-intensification to a TS.

Thus far the UK and the ECMWF have been the best so far in handling the dual ridge structures, one over the southern US, the other over the Atlantic, so I would continue to lean towards them for guidance. The 12Z of both of these models just came out and appear as follows:

UK

post-378-0-48312600-1312395675.gif

ECMWF

post-378-0-59108200-1312395680.gif

At this point, were I to adjust my track forecast, I would take it further east, with a landfall somewhere in S. FL before recurving. I still do not forsee Emily ever becoming a hurricane, but it may be possible post-recurvature once she's no longer a threat to land and close to extratropical transition.

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This is also fairly well timed with the greatest amount of downsloping dry flow coming off the peaks.

The stuff firing NE of the center is likely part of what Phil was saying... frictional convergence on the windward side of the island.

For the dying convection, it is most likely a combination of shear and lee flow being wrapped, IMO.

Maybe, but when I said "NE of the center", I meant the strongest growth of convection just NE of the center. Not the stuff over and southeast of Hispaniola. Seems a bit too far away from the island to be frictional convergence due to land... maybe just enough lift from an outflow boundary from the collapsing thunderstorms just to the west?

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