NATL: MELISSA - Aftermath - Discussion: Josh Morgerman video of Melissa is up

[cycloneye]

The sad part of all of what will transpire in the next few days is well ilustrated by Papín in the 5 PM discussion.

Unfortunately, it is becoming increasingly likely that Melissa will become a large and
dangerous hurricane by the end of the forecast period.

[Teban54]

The sad part of all of what will transpire in the next few days is well ilustrated by Papín in the 5 PM discussion.

Unfortunately, it is becoming increasingly likely that Melissa will become a large and
dangerous hurricane by the end of the forecast period.

The sentence just before:

This forecast is in the best agreement with the HCCA intensity aid, but it is worth noting it's under the latest HAFS-A/B and HMON forecasts.

[Teban54]

Also worth noting that according to NHC/Papin, Melissa already had a center reformation last night -- which still didn't result in any further intensification today that models like GFS were calling for. Even if yet another relocation happens, my guess is that it won't improve Melissa's structure until the shear finally lets up.

The current vortex misalignment of Melissa is a significant impediment to short-term intensification, and the vertical wind shear is expected to maintain this tilted structure over the next 24-36 hours, although I can't preclude any center reformations down-shear, like what occurred last night. After this period, the ECWMF-SHIPS guidance now indicates the ongoing westerly shear will decrease to 10-15 knots, and the storm remains over very warm sea-surface temperatures and high oceanic heat content.

[cycloneye]

The historic part if it happens.

 https://x.com/philklotzbach/status/1981105873218089347

[Teban54]

The historic part if it happens.

 https://x.com/philklotzbach/status/1981105873218089347

Seasonal totals for each of these seasons:

• 1932: 15 / 6 / 4
• 1999: 12 / 8 / 5
• 2010: 19 /12 / 5
• 2025: 13 / 5 / 4, if Melissa becomes MH

Even among these, 2025 would still have the most bizarre distribution by far. The 4th Cat 4 in both 1999 and 2010 were in mid-September, allowing time for 3 and 7 more hurricanes to form in the next 1.5 months, respectively (each season having one more MH). 2025 is much less likely to get a "normal" TS/H/MH ratio this way with its remaining time.

1932, despite pre-satellite issues, would be the closest comparison... Which is even more ominous, as its 4th MH was the infamous Cuba 1932, which peaked at 150 kt, had a ship-measured pressure of 915 mb, and also had the longest duration as a Cat 5 (3 days 6 hours) -- in November.

[Hurricane Mike]

6pm Video Update
https://youtu.be/gjIeLB72dvg

[blp]

Story of the last 24 hours. Look at how much the shear has increased over the system. This is what the GFS did not see coming.

24hours ago.


Now:

[Hurricane Mike]

Story of the last 24 hours. Look at how much the shear has increased over the system. This is what the GFS did not see coming.

24hours ago.
https://i.ibb.co/KjSByY5b/wg8shr-Z-8.gif

Now:
https://i.ibb.co/0yTjhyvZ/wg8shrZ.gif

Yeah, and it could wind up hurting us in the long run. Same thing happened with Hurricane Michael back in 2018. The shear kept it in check long enough so that when it finally did explode, it was hitting land.

[ScottNAtlanta]

This is the most insane intensity spread I have ever seen

[al78]

Just looking and reading about Melissa, this looks to be a case where the storm is over waters with a high enough heat content to theoretically support a cat 5 hurricane (i.e. MPI is high) and it is all about the atmosphere. I'm guessing that if atmospheric conditions become favourable, it will be like lifting a lid and this thing will explosively intensify. I am thinking the forecasters at the NHC are thinking along similar lines. The big question is, where does it go if it does rapidly intensify and is anywhere likely to get absolutely hammered? It is wait and see at the moment.

[Nimbus]

18z GFS gets the storm north of Hispaniola by 114 hours a little quicker than the 12Z run.
18Z Euro will probably show the trough miss again with devastation for Jamaica.

18z GFS could be moving it out earlier to avoid the ridge capture scenario?

Typical October front digging deep into the Caribbean.

[hipshot]

18z GFS gets the storm north of Hispaniola by 114 hours a little quicker than the 12Z run.
18Z Euro will probably show the trough miss again with devastation for Jamaica.

18z GFS could be moving it out earlier to avoid the ridge capture scenario?

Wouldn't any ridge to the north force the storm more west until the ridge gets further east and Mellisa would then get drawn north.
But how far west does Mellisa get before that happens.

[chaser1]

Technically, there already is a weak ridge centered over the W. Bahamas right now. The New England trough is not quite deep enough to full degrade that weak ridging. Nor is Melissa deep enough of a low to further contribute to eroding that ridge. That pretty much has resulted in Melissa sitting nearly stationary in a COL more or less. Melissa begins to deepen some and one of those variables begin to slowly change resulting in a slightly greater tug to the north. That in turn would probably (slightly) further the degradation of the weak ridge cause a somewhat greater gap to escape poleward.

[blp]

Recon confirms the swirl we saw west of the convection is still the center.

[TallyTracker]

Recon confirms the swirl we saw west of the convection is still the center.

https://i.ibb.co/svxGrgWV/recon-AF308-0513-A-MELISSA.png

That is a poorly defined center as well. With those flight-level winds, I’d say it’s 40-45 mph currently. I think 50 mph is generous.

[LarryWx]

Recon confirms the swirl we saw west of the convection is still the center.

https://i.ibb.co/svxGrgWV/recon-AF308-0513-A-MELISSA.png

That is a poorly defined center as well. With those flight-level winds, I’d say it’s 40-45 mph currently. I think 50 mph is generous.

The 8PM NHC update increased the lowest SLP from 1000 mb to 1002 mb.

[chaser1]

Recon confirms the swirl we saw west of the convection is still the center.

https://i.ibb.co/svxGrgWV/recon-AF308-0513-A-MELISSA.png

That is a poorly defined center as well. With those flight-level winds, I’d say it’s 40-45 mph currently. I think 50 mph is generous.

The 8PM NHC update increased the lowest SLP from 1000 mb to 1002 mb.

We'll probably see another 2-4 MB rise before she gets her act together. If that swirl is/was the LLC then frankly it's not far from becoming ill-defined. Sure, plenty of west winds appear evident but I was beginning to question whether they still existed around a cohesive surface feature or primarily above the surface.

[LarryWx]

That is a poorly defined center as well. With those flight-level winds, I’d say it’s 40-45 mph currently. I think 50 mph is generous.

The 8PM NHC update increased the lowest SLP from 1000 mb to 1002 mb.

We'll probably see another 2-4 MB rise before she gets her act together. If that swirl is/was the LLC then frankly it's not far from becoming ill-defined. Sure, plenty of west winds appear evident but I was beginning to question whether they still existed around a cohesive surface feature or primarily above the surface.

The lowest SLP on record I could find for a center landfalling on Jamaica is 958 mb (MH Charlie of 1951) followed by 960 mb for MH Gilbert. So, the 18Z Euro’s 943 mb would shatter the current record.

Do you or does anyone else know if there has ever been a pressure recorded lower than 958 mb there? If so, when and do you have a link?

[Sciencerocks]

[cycloneye]

AL, 13, 2025102300, , BEST, 0, 143N, 745W, 45, 1002, TS