ATL: JOSEPHINE - Remnants - Discussion

[GCANE]

Southern flank starting to tighten up.

[al78]

At this point it probably won’t even get a name. Definitely underperforming!

The MDR seems like it's cursed (or blessed, depending on how you look at it )

Kind of strange that we've had so much dry air and MDR struggles for so many back to back seasons, especially since nothing's really struggled elsewhere.

Not sure I agree on that one. 2017 had two Category 5s and a near-Category 5 in the MDR - all after August 30. 2018 had four hurricanes in the MDR despite a much cooler than normal MDR, three of which were in September. 2019 had no hurricanes in the MDR prior to September 18, then it had Jerry (a Category 2) and Lorenzo (a high end Category 4 in the MDR). If anything, the Caribbean has been the part of the basin that has been struggling lately (unless you are referring to the Caribbean as part of the MDR in this case).

2018 is actually a good example of a struggling MDR. The one big hurricane (Florence) that formed there didn't get going until it had moved north into the sub-tropics. If you look at the MDR west trackers they mostly spluttered along at TD or TS strength. Helene was one that reached cat 2 in the MDR, probably because it formed very far east where the MDR was more favourable, but the other two hurricanes were cat 1 for merely a day, although one was a July hurricane so no surprise it didn't last very long. 2018 was an active year almost entirely because of the favourable subtropical Atlantic, it was one of the most active for subtropical activity since at least 1950.

[wxman57]

Southern flank starting to tighten up.

https://i.imgur.com/rWdCj1k.png

Those clouds you highlighted are moving southward, not in toward the center. I do see what could be the LLC where I have my crosshairs, which corresponds to the NHC position at 13.69N / 49.15W.

[eastcoastFL]

Most of the models kill the system after 84 hrs and then bring it back to life as TD towards the end of the run. Thankfully it appears to be a fish but there seems to be debate amongst the models as to if she survives and if she stays dead...

[cheezyWXguy]

Convection looks to be getting stripped away to the NW of the center, could be exposed again soon.

[eastcoastFL]

Looking at 12Z GFS shear 30+ hrs out.
Any track of Joe south of current forecast and that shear will not be shear but a very well developed outflow channel.
A lot of convective debris already flowing into the Bahamas from the convection off SC coast.
The more it sits there and fires, the more the upper-levels become to allow Joe to survive the guillotine.

I see what you’re saying looking at the shear forecast right now. Any shift in track southward would leave an opening to avoid the shear. Also we’ve seen shear not where it should be many times in the past in just a few hours time never mind 24+ hrs. If the shear dissipates or moves further NE quicker than forecast that same window opens. Perhaps that’s why some models are keeping Josephine alive longer than others. Shear is still very difficult to forecast. I’m also curious where the anti cyclone will be.

[eastcoastFL]

Convection looks to be getting stripped away to the NW of the center, could be exposed again soon.

NW convection seems to be pushing up on that 30 kts of shear.

[eastcoastFL]

Whatever happens with this storm if it’s gonna be a fish I hope it stays alive in some form so we can track it and learn a few more things. Isaias wasn’t not a spectacular storm but it was impressive to watch and learn from as it defied the odds and the naysayers over and over again. As a complete amateur and simply a weather enthusiast I felt like I learned quite a bit from that little storm. That and I’m completely stocked up and ready for whatever comes next because of him. Can’t afford to buy a generator again to keep the next one away... does that trick last all season or is it a one time bargain?

[cheezyWXguy]

Convection looks to be getting stripped away to the NW of the center, could be exposed again soon.

Aaand there it is. Pretty confident that’s the bottom half of the center now exposed on the south end of the main convection.

[GCANE]

Convection looks to be getting stripped away to the NW of the center, could be exposed again soon.

NW convection seems to be pushing up on that 30 kts of shear.

At least it confirms it's not an open wave.
Its a pretty sharp shear gradient.

[Aric Dunn]

Convection looks to be getting stripped away to the NW of the center, could be exposed again soon.

NW convection seems to be pushing up on that 30 kts of shear.

At least it confirms it's not an open wave.
Its a pretty sharp shear gradient.

Definitely a closed well defiend circ .. There never was any real doubt amongst the decision makers. the center just keeps getting tugged along from the undercutting mid level shear. as soon as that lets up ... even a little bit and it will deepen.

in a deep moisture pouch and if we still have SE shear it has yet to transition to low shear before it flips sides to SW shear. meaning we still have 48 hours -ish of time to deepen.

[GCANE]

NW convection seems to be pushing up on that 30 kts of shear.

At least it confirms it's not an open wave.
Its a pretty sharp shear gradient.

Definitely a closed well defiend circ .. There never was any real doubt amongst the decision makers. the center just keeps getting tugged along from the undercutting mid level shear. as soon as that lets up ... even a little bit and it will deepen.

in a deep moisture pouch and if we still have SE shear it has yet to transition to low shear before it flips sides to SW shear. meaning we still have 48 hours -ish of time to deepen.

Also means that this may track a little more south then current forecast.
Could keep from having her head chopped in the Bahamas.

[wxman57]

Nothing I'm looking at convinces me there is a well-defined LLC. This morning's ASCAT indicated more of a sharp wave axis. I see a mid-level rotation associated with diminishing convection and what looks like a weak LLC near 14N/49.9W (red crosshairs). Outflow boundaries from SE to north of the center. Little or no convergence toward any LLC. I'm not sure recon would be able to close off an LLC. Doesn't matter if it goes due west or northwest, it's heading for strong shear. I think that the NHC had serious questions about whether or not there was a circulation, but since ASCAT indicated TS winds, they decided to upgrade it in case some of those squalls were to affect any land areas. Of course, since none of us was involved in the NHC's decision, all we can do is guess what reasoning they had. To me, looks like they named a tropical wave "Josephine" to be on the safe side for island residents.

[SouthDadeFish]

Nothing I'm looking at convinces me there is a well-defined LLC. This morning's ASCAT indicated more of a sharp wave axis. I see a mid-level rotation associated with diminishing convection and what looks like a weak LLC near 14N/49.9W (red crosshairs). Outflow boundaries from SE to north of the center. Little or no convergence toward any LLC. I'm not sure recon would be able to close off an LLC. Doesn't matter if it goes due west or northwest, it's heading for strong shear. I think that the NHC had serious questions about whether or not there was a circulation, but since ASCAT indicated TS winds, they decided to upgrade it in case some of those squalls were to affect any land areas. Of course, since none of us was involved in the NHC's decision, all we can do is guess what reasoning they had. To me, looks like they named a tropical wave "Josephine" to be on the safe side for island residents.

http://wxman57.com/images/Josephine3.JPG

Totally agree with you. That's exactly what I'm seeing too. Even if we may be the only two on here seeing that

[Nimbus]

Center has been almost exposed on the south side of the convection all afternoon.
Low level cloud motion is vigorous, no doubt there are tropical storm force winds.
12Z HWRF and GFS Model runs have Josephine making the 20-60 corner of the Hebert box largely intact, but the strength forecast trend is weakening at that point.

[SouthDadeFish]

Now lets see how the models react to a 45 mph TS and a 10 mb lower pressure vs an open wave lol

back to force feeding the models again..

I want to clarify something here: Global models don't give a hoot what NHC sets the best track intensity at. They assimilate millions of observations that also don't care what NHC sets the best-track at. It's really only matters for the statistical models.

[cycloneye]

 https://twitter.com/pppapin/status/1293997202172502016

[GCANE]

I got an idea.
Let's call this a negative-tilt wave with a cherry on top.

[Aric Dunn]

For those going crosseyed by the mirage farther east.. the center has just now become exposed farther west.

[GCANE]

For those going crosseyed by the mirage farther east.. the center has just now become exposed farther west.

https://i.ibb.co/PWkRQYJ/Capture.png


https://i.ibb.co/bmn51sV/4.gif

OK
This one is a toilet being flushed with a pickle on top