ATL: KIRK - Remnants - Discussion

[MWatkins]

Just an estimate that the 99.9% chance of not making hurricane status might need to be adjusted downward, just in case anyone may have made that type of deterministic proclamation. We still don't understand exactly why some storms strengthen (like Kirk is now) and most don't given the current environment.

Also worth noting that while significant, the models have backed off the strong 850-200mb shear a little and it has more of a SW component in the next 72 hours relative to the same solutions 120 hours out at the same verify time.

The environment around and north of Kirk is changing as some of the blocking is breaking down. I am expecting the model guidance to spread out over the next several runs (which has already started BTW).

Mike

[Emmett_Brown]

Just an estimate that the 99.9% chance of not making hurricane status might need to be adjusted downward, just in case anyone may have made that type of deterministic proclamation. We still don't understand exactly why some storms strengthen (like Kirk is now) and most don't given the current environment.

Also worth noting that while significant, the models have backed off the strong 850-200mb shear a little and it has more of a SW component in the next 72 hours relative to the same solutions 120 hours out at the same verify time.

The environment around and north of Kirk is changing as some of the blocking is breaking down. I am expecting the model guidance to spread out over the next several runs (which has already started BTW).

Mike

This shear reminds me a little of the shear Florence encountered; which knocked her down to a TS, while imparting a more northerly component of motion while doing so. It would be cool if there was a mission to sample the atmosphere around Kirk to get a better picture of the shear, and help us understand why he strengthened today instead of "decloaking".

[MississippiWx]

60mph seems a bit conservative. Kirk is making a run at hurricane status, if not there already.

[Aric Dunn]

Next recon is on the way.. I say its up to 70mph.. with some questionable hurricane readings that will be debated. lol

[meriland29]

He is definitely looking lively today. If he has another 2 days before that sheer and dry air hit him, I wouldnt be surprised if he was already a substantial hurricane by then. The NHC doesn't seem to think that would matter given the intensity of the pending sheer, and that it will strip him down to his roots since they only expected him to be a TS at that point, leaving him without much to lose...but, in my humble, non-expert opinion I feel like, because he will likely be stronger than NHC anticipated, that it would be less likely to have the time to strip him down to a low/wave by the time he leaves that area into more favorable waters...correct me if I am wrong(?)



Also, side note, does it look like he is already injesting that air on the left? Or is it just him spinning up (literally)

[Hammy]

Definitely some loss of organization over the last few hours. Some flattening of the western edge, and the deepest convection is now quite a ways away from the center. May have been 55kt earlier but likely peaked and we won't see much difference on the next flight vs the earlier one. I would venture to guess the center's near 13.1N/55.7W, just west of the westernmost tower.

[MississippiWx]

https://i.imgur.com/1qv4ZZl.jpg

Definitely some loss of organization over the last few hours. Some flattening of the western edge, and the deepest convection is now quite a ways away from the center. May have been 55kt earlier but likely peaked and we won't see much difference on the next flight vs the earlier one. I would venture to guess the center's near 13.1N/55.7W, just west of the westernmost tower.

Funny. Looks like to me like it has increased banding and convection has rotated further west over the center. Looks better organized to me.

[AutoPenalti]

I believe Kirk will be at most a high-end TS by the time Recon hits. It does appear to be blowing up more hot towers as we approach sunset but the western periphery seems to be disorganizing, furthermore, Kirk will meet its demise with the impending shear out in front. Honestly, I've been very pessimistic about this storm, maybe because of all the Star Trek memes.

[Nimbus]

The subtropical ridge is getting pumped a little by the outflow but we usually have to wait for the models to establish a changing trend over several runs. Models have better layer data than watching the water vapor imagery. The Carribean hasn't changed color to orange so I'm not sure where the dry air will be coming from?

[chaser1]

Just an estimate that the 99.9% chance of not making hurricane status might need to be adjusted downward, just in case anyone may have made that type of deterministic proclamation. We still don't understand exactly why some storms strengthen (like Kirk is now) and most don't given the current environment.

Also worth noting that while significant, the models have backed off the strong 850-200mb shear a little and it has more of a SW component in the next 72 hours relative to the same solutions 120 hours out at the same verify time.

The environment around and north of Kirk is changing as some of the blocking is breaking down. I am expecting the model guidance to spread out over the next several runs (which has already started BTW).

Mike

This shear reminds me a little of the shear Florence encountered; which knocked her down to a TS, while imparting a more northerly component of motion while doing so. It would be cool if there was a mission to sample the atmosphere around Kirk to get a better picture of the shear, and help us understand why he strengthened today instead of "decloaking".

Let me put this out there as more a theoretical question then conclusion. I have long viewed shear as a overly-simplistic cause of primarily 200mb winds that essentially decapitate and disrupt both, the very protective core of convection rotating around center as well as the more divergent relaxed upper level anticyclonic. Nonetheless, while the latter could reasonably still act as a strong outflow jet it's logical that this would probably result in a increasingly tilted vertical structure (unless forward storm motion was inline with the direction of upper level shear thus decreasing the net shear), right up until the point where the storm itself becomes more shallow itself. Still, to me this would seem to cause a relatively less rapid weakening to the storm itself assuming continued convective bursting and surface convergence continued. However, the former impact of upper level shear where the higher cloud tops begin to shear off and thus more immediately degrade the core structure around the point where the focused rising column of air exists, would seem to have a more immediate impact on disrupting and maintaining the LLC itself. Even now with Kirk, it seems apparent that Kirk's own outflow seems to at least be winning the temporary battle and looks to equally push back on the encroaching winds however.

That all said, it's only in recent years that i've really come to notice a different type of shear that seemed to exist below the 200mb level, that in some cases still undercut and disrupted the mid to upper circulation (roughly 600mb - 250 mb perhaps?). I'm sure this isn't any "newly" discovered cause for some tropical cyclones to prematurely degenerate and weaken, but it is something that I only more recently have come to (kind of) understand. So....... with all that said, is it plausible that with Kirk, we are seeing a somewhat lower height shear which is plainly seen on satellite but that has continually been forecast to undercut and cause upper level shear/weakening of the storm, BUT given a directional flow a bit more from the WSW, that it still somehow aids and "worked-into" the higher level counterclockwise circulation of the storm? My understanding is that the upward flow aloft generally weakens (or decreases) with height; Could this act as a feature that more or less serves as an additional "rip-cord" increasing spin?? Granted, the counterproductive impact still results in causing a less vertically aligned low to mid level column all the while.

[chaser1]

Next recon is on the way.. I say its up to 70mph.. with some questionable hurricane readings that will be debated. lol

I'll see your 70 and raise it 5 (with gusts to 85 NE quad and 1003 pressure)

[moja.ram]

Next recon is on the way.. I say its up to 70mph.. with some questionable hurricane readings that will be debated. lol

I'll see your 70 and raise it 5 (with gusts to 85 NE quad and 1003 pressure)

I'll see your 75, I raise it 10 .....

[meriland29]

Next recon is on the way.. I say its up to 70mph.. with some questionable hurricane readings that will be debated. lol

I'll see your 70 and raise it 5 (with gusts to 85 NE quad and 1003 pressure)

I'll see your 75, I raise it 10 .....

Y'all getting out of hand here

[Hammy]

I'll place my bet on 60, since we have about an hour left.

[floridasun78]

kirk will be on life support soon

[moja.ram]

kirk will be on life support soon

Are you shear?

[Aric Dunn]

THe center in the past couple hours has been pulled way back into the convection with some very high tops starting to overshoot right where it is..

recon will get there at an interesting time.

still despite all the shear forecast, the outflow continues to expand west and the upper level wind direction to its west continues to become more southerly and backing west..

at least for the time being.

[meriland29]

Definitely popping some serious cold clouds the last few frames ..

[BYG Jacob]

THe center in the past couple hours has been pulled way back into the convection with some very high tops starting to overshoot right where it is..

recon will get there at an interesting time.

still despite all the shear forecast, the outflow continues to expand west and the upper level wind direction to its west continues to become more southerly and backing west..

at least for the time being.

This season has a habit of having storms push back against shear, wonder why.

[Weatherwatcher2018]

What effects should barbados expect as the system is now forecast to pass to the north