ATL: LAURA - Post-Tropical - Discussion

[NDG]

After looking at the euro more closely it has captured this evolution well East side poofs, west side fires for a bit then poofs.

Clout tops are warming as we speak.

But if you closely it gets the east side to become a very broad weak vorticity with the west side start rotating around it and then goes poof.
Very doubtful of that happening by looking at the system this morning.

[eastcoastFL]

Good news is there’s no more cat 5 on the intensity guidance

[NDG]

DATE/TIME LAT LON CLASSIFICATION STORM
19/1130 UTC 11.5N 44.6W T1.5/1.5 98L
19/0530 UTC 11.6N 43.4W T1.5/1.5 98L
18/2330 UTC 11.7N 42.3W T1.0/1.0 98L
18/1730 UTC 11.8N 42.0W T1.0/1.0 98L

T Values going up... I's place the circulation center closer to 12.0N...

If anything the Best track shows the CoC moving south of due west.

[shiny-pebble]

When does the next ASCAT come in??

Sent from my SM-G970U using Tapatalk

[Aric Dunn]

Good news is there’s no more cat 5 on the intensity guidance

https://www.tropicaltidbits.com/storminfo/98L_intensity_latest.png

probably only because of land interaction.

[tiger_deF]

98L is looking great this morning, while it doesn't have any kind of CDO the spin is vigorous, the eastern lobe appears to be dying out, banding is already somewhat evident, and upper level conditions will be ripe at least for the next few days

[toad strangler]

One thing to watch is 98L on the SW side of that retrograding TUTT. That would be the most conducive place to be for said TUTT to aid in development.

[SFLcane]

DATE/TIME LAT LON CLASSIFICATION STORM
19/1130 UTC 11.5N 44.6W T1.5/1.5 98L
19/0530 UTC 11.6N 43.4W T1.5/1.5 98L
18/2330 UTC 11.7N 42.3W T1.0/1.0 98L
18/1730 UTC 11.8N 42.0W T1.0/1.0 98L

T Values going up... I's place the circulation center closer to 12.0N...

Needs to be at least 2.0 for a TC. With cloud tops warming maybe no upgrade today.

[Aric Dunn]

Upcoming ASCAT will likely a show a TD.

and some other vorts well to the WSW and remnants of the eastern lobe to the NE of it. but the overall Circ of 98L has become much more circular.

[SFLcane]

Upcoming ASCAT will likely a show a TD.

and some other vorts well to the WSW and remnants of the eastern lobe to the NE of it. but the overall Circ of 98L has become much more circular.

Post it if you get to it.

[wx98]

Mind blowing that the Euro and its ensembles dropped all development with 98L, but when I see 98L this morning getting better organized than what it was 24 hrs ago I have no option but to dismiss the Euro.
Clearly the western vorticity is taking over and the vorticity that was to its east is weakening as it started rotating around the larger gyre of the monsoon trough.

https://i.imgur.com/vQhAdnY.gif

Is it possible the euro initialized on the dissipating low to the east?

Is initialized well, but it does show the eastern vorticity taking over as it rotates westward and the western vorticity dying out later today, we will see if it is right, but doubtful.

https://i.imgur.com/PmG24xZ.gif

If the western vort is what they would begin issuing advisories on, and this shows the eastern vort taking over, maybe they are waiting until one completely dies so the other can become dominant. That way they don’t begin tracking a dying vort.

[eastcoastFL]

06z models. I like the COTI. I’ll take one of those please

[eastcoastFL]

DATE/TIME LAT LON CLASSIFICATION STORM
19/1130 UTC 11.5N 44.6W T1.5/1.5 98L
19/0530 UTC 11.6N 43.4W T1.5/1.5 98L
18/2330 UTC 11.7N 42.3W T1.0/1.0 98L
18/1730 UTC 11.8N 42.0W T1.0/1.0 98L

T Values going up... I's place the circulation center closer to 12.0N...

Needs to be at least 2.0 for a TC. With cloud tops warming maybe no upgrade today.

Nhc is still giving a 48 hr window on formation so highly likely it doesn’t happen until at least tomorrow morning

[Shell Mound]

Good news is there’s no more cat 5 on the intensity guidance

https://www.tropicaltidbits.com/storminfo/98L_intensity_latest.png

I wouldn’t rely so much on the 06Z/18Z guidance, which does ingest the full range of data that are incorporated into the 00Z/12Z cycles. If anything, if one compares the latest 06Z guidance vs. yesterday’s 18Z output, the consensus has actually trended upward; most of the members at 18Z showed a borderline TS/hurricane on 25 August, while the 06Z output has trended toward a solid hurricane or even low-end Category 2 on that date, shortly prior to possible interaction with Hispaniola, which is far from certain and probably less likely to occur, given the faster-than-forecast rate of short-term organisation currently ongoing. Oh, and for once I wouldn’t give either the operational GFS or the entire EPS suite much weight in terms of intensity, for reasons others have already enumerated.

[Aric Dunn]

I place the center 11.6N 45.2W

[tiger_deF]

06z models. I like the COTI. I’ll take one of those please

https://www.tropicaltidbits.com/storminfo/98L_tracks_latest.png

Would there be any set of conditions that could theoretically even cause such a trajectory?

[eastcoastFL]

Good news is there’s no more cat 5 on the intensity guidance

https://www.tropicaltidbits.com/storminfo/98L_intensity_latest.png

I wouldn’t rely so much on the 06Z/18Z guidance, which does ingest the full range of data that are incorporated into the 00Z/12Z cycles. If anything, if one compares the latest 06Z guidance vs. yesterday’s 18Z output, the consensus has actually trended upward; most of the members at 18Z showed a borderline TS/hurricane on 25 August, while the 06Z output has trended toward a solid hurricane or even low-end Category 2 on that date, shortly prior to possible interaction with Hispaniola, which is far from certain and probably less likely to occur, given the faster-than-forecast rate of short-term organisation currently ongoing.

So far everything but the Euro develops this. Euro is the outlier going poof. All but the GFS show a cane. 00z Gfs had a hurricane but the 06z has a weird 1007 TD/Ts floating around the gulf

[eastcoastFL]

06z models. I like the COTI. I’ll take one of those please

https://www.tropicaltidbits.com/storminfo/98L_tracks_latest.png

Would there be any set of conditions that could theoretically even cause such a trajectory?

I don’t think so. It would take some weird breakdown in the ridge to the north and north east I would guess

[NDG]

Is it possible the euro initialized on the dissipating low to the east?

Is initialized well, but it does show the eastern vorticity taking over as it rotates westward and the western vorticity dying out later today, we will see if it is right, but doubtful.

https://i.imgur.com/PmG24xZ.gif

If the western vort is what they would begin issuing advisories on, and this shows the eastern vort taking over, maybe they are waiting until one completely dies so the other can become dominant. That way they don’t begin tracking a dying vort.

No advisories yet when a well defined surface closed circulation is still not present, even the most aggressive models, HWRF & ICON, do not show a well defined closed circulation until at least tomorrow.

[wx98]

06z models. I like the COTI. I’ll take one of those please

https://www.tropicaltidbits.com/storminfo/98L_tracks_latest.png

Would there be any set of conditions that could theoretically even cause such a trajectory?

I don’t think so. It would take some weird breakdown in the ridge to the north and north east I would guess

Unless that was showing some kind of Fujiwhara interaction between the vorts that swings it south and back east, but I’m not sure about that.