NATL: MELISSA - Hurricane - Discussion

[Teban54]

[Hayabusa]

Wow! Look that CI!

2025OCT27 024021 7.4 908.3 152.0 7.4 8.0 8.0 NO LIMIT OFF OFF OFF OFF 19.14 -78.47 EYE 16 IR 73.8 16.25 77.45 ARCHER GOES19 19.2
2025OCT27 031021 7.5 905.1 155.0 7.5 8.1 8.2 3.7T/24hr OFF OFF OFF OFF 18.30 -79.68 EYE 15 IR 73.8 16.25 77.45 ARCHER GOES19 19.2
2025OCT27 034021 7.7 898.7 161.0 7.7 8.3 8.3 NO LIMIT OFF OFF OFF OFF 18.12 -79.97 EYE 15 IR 73.8 16.28 77.51 ARCHER GOES19 19.3
2025OCT27 041021 7.8 895.5 164.0 7.8 8.0 8.0 NO LIMIT OFF OFF OFF OFF 18.96 -78.14 EYE 15 IR 73.8 16.27 77.57 ARCHER GOES19 19.2
2025OCT27 051021 8.0 888.9 170.0 8.0 8.2 8.2 NO LIMIT OFF OFF OFF OFF 18.84 -78.98 EYE 15 IR 73.8 16.28 77.60 ARCHER GOES19 19.3
2025OCT27 053021 8.1 885.5 173.0 8.1 8.1 8.1 NO LIMIT OFF OFF OFF OFF 18.78 -78.86 EYE 15 IR 73.8 16.28 77.60 ARCHER GOES19 19.3
2025OCT27 054021 8.1 885.5 173.0 8.1 8.1 8.1 NO LIMIT OFF OFF OFF OFF 19.92 -78.79 EYE 15 IR 73.8 16.30 77.66 ARCHER GOES19 19.3
2025OCT27 061021 8.1 885.5 173.0 8.1 8.1 8.1 NO LIMIT OFF OFF OFF OFF 19.80 -78.55 EYE 15 IR 73.8 16.31 77.69 ARCHER GOES19 19.3
2025OCT27 064021 8.1 886.5 173.0 8.1 8.0 8.0 NO LIMIT OFF OFF OFF OFF 20.72 -78.25 EYE 14 IR 73.8 16.28 77.72 ARCHER GOES19 19.3
2025OCT27 071021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 20.16 -78.22 EYE 13 IR 73.8 16.29 77.72 ARCHER GOES19 19.3
2025OCT27 074021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 20.87 -78.24 EYE 14 IR 73.8 16.33 77.75 ARCHER GOES19 19.3
2025OCT27 081021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 20.34 -78.39 EYE 14 IR 73.8 16.31 77.75 ARCHER GOES19 19.3
2025OCT27 084021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 20.04 -78.20 EYE 15 IR 73.8 16.35 77.78 ARCHER GOES19 19.4
2025OCT27 091021 8.1 886.5 173.0 8.0 8.1 8.1 NO LIMIT ON OFF OFF OFF 20.31 -78.54 EYE 14 IR 73.8 16.35 77.80 ARCHER GOES19 19.4
2025OCT27 094021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 19.26 -78.00 EYE 14 IR 73.8 16.39 77.84 ARCHER GOES19 19.4
2025OCT27 101021 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 21.02 -78.15 EYE 14 IR 73.8 16.36 77.89 ARCHER GOES19 19.4
2025OCT27 111022 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 20.63 -78.16 EYE 15 IR 73.8 16.36 77.95 ARCHER GOES19 19.4
2025OCT27 113022 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 21.31 -78.21 EYE 14 IR 73.8 16.36 77.95 ARCHER GOES19 19.4
2025OCT27 114022 8.1 886.5 173.0 8.0 8.0 8.0 NO LIMIT ON OFF OFF OFF 21.69 -78.14 EYE 14 IR 73.8 16.35 77.99 ARCHER GOES19 19.4
2025OCT27 121020 8.1 886.5 173.0 8.0 7.9 7.9 NO LIMIT ON OFF OFF OFF 21.05 -77.95 EYE 14 IR 73.8 16.34 78.00 ARCHER GOES19 19.4
2025OCT27 124020 8.1 886.5 173.0 7.9 7.9 7.9 NO LIMIT ON OFF OFF OFF 21.81 -77.72 EYE 14 IR 73.8 16.35 78.05 ARCHER GOES19 19.4
2025OCT27 131020 8.0 889.8 170.0 7.9 7.8 7.8 NO LIMIT ON OFF OFF OFF 21.90 -77.31 EYE 14 IR 73.8 16.31 78.09 ARCHER GOES19 19.4

[Stormgodess]

Longitude is just about at the west end of Jamaica with it wobbling to the SW.
I don't know.

Could Melissa's ugly blob eastern twin be affecting her track? It's as big as she is.

I know nothing, so I panicked for a second when I saw this loop, it looked like the ugly twin was forming an eye


 https://x.com/BradyBGWX/status/1982807170568618209

[BobHarlem]

Looks like the west motion has stopped, may be doing a small cyclonic loop then start the north drift.

[chaser1]

This season is really odd with now THREE C5s, and everything else not named Erin, Humberto, Gabrielle and Imelda ended up underwhelming, yet were likely to end with above-average ACE. Very weird.

Also that dropsonde is insane and I think is the highest gust (210 kt) measured in a TC in a dropsonde besting out Megi by 1 kt..

Very 1999 or 2007-like in that sense. The overall conditions/storm strength behavior this year were very binary. Storms that didn't have optimal conditions to strengthen greatly struggled, and storms that did massively overperformed.

We need to create a new broad time span view metric; Sort of a "Volatility Gradient". As a graph however, I do not think that a range of results would at all correlate with any graph that simply tracks seasonal Instability verses Stability (conditions). I'm sure that someone must have conducted a similar thesis paper with that in mind

[Jr0d]

I should be sleeping, been up all night but now I have to wait for the NHC discussion and hopefully one more AF recon eye pass.

I saved the dropsonde plot image from Tropical Tidbits that shows the 210kt winds. Can't sleep after seeing that.

[Sanibel]

Looks like the west motion has stopped, may be doing a small cyclonic loop then start the north drift.

Agreed...Starting to look like a killer hurricane...

The blob is convergence from the tropical flow easterlies piling up against a stalled Low...

[Chris_in_Tampa]

9am EDT Monday: A sonde just measured what might be one of the highest winds ever recorded by sonde, if accurate

Please keep the following in mind. This is a momentary wind recorded as the sonde falls. It's a fraction of a second I believe. Maybe around 0.25 or 0.5 seconds, I'm not sure. Not 1 minute sustained or even a gust which I think is 3 seconds.

In the following particular sonde these pressure levels are this high in geopotential feet:

925mb level is 144 ft
850mb level is 2,572 ft

At the 907mb level, a momentary wind of 242 mph was recorded.

At the surface, 162mph.

Here's the sonde:
https://hurricanecity.com/recon/recon.c ... duct=sonde

Some of the of the other readings on the way down were 222mph, 220mph, 220mph, 213mph.

Some historical comparisons from browsing my recon archive. (I didn't search with a program, just looking at some of the top Atlantic storms in history) These are significant levels reported in the dropsonde, not from raw dropsonde data. If recon wasn't in a storm at the time of peak winds, it obviously would not have caught the highest. And also obviously, a sonde is unlikely to just happen to just catch the highest winds as it gets violently thrown around. And this and some of these others could be errors. This is raw unverified data that is subject to error. Also, my archive might have missed some.

I'm not saying this is a complete list, just some of the ones I looked up.

Katrina in 2005 had one for a single reading of 269mph:
https://tropicalatlantic.com/recon/reco ... 3-919-234-

Some of the of the other readings on the way down were 213mph, 212mph, 208mph, 207mph.

Rita in 2005 had one at 236mph.

Irma in 2017 had 229mph.

Dorian in 2019 had one at 224mph and another on another mission of 223mph.

Milton in 2024 had 218mph.

Felix in 2007 had 214mph.

Dean in 2007 had 205mph.

Maria in 2017 had 199mph.



Also added Isabel in 2003 to that list: It had 227mph

I was curious and asked ChatGPT and it said 203 knots. Well, maybe in 2003 when the article it found was from:
https://www.aoml.noaa.gov/hrd/hurdat/mwr_pdf/2003.pdf

"The highest winds measured by reconnaissance aircraft were 158 kt at 700-mb flight level and 157 kt at 2560 m between 1700 and 1730 UTC 13 September. A 156-kt 700-mb wind was observed at 1719 UTC 12 September. Stronger winds were observed from GPS dropsondes in the eyewall, with a maximum of 203 kt reported at 806 mb (1372 m) at 1753 UTC 13 September. This is the strongest wind ever observed in an Atlantic hurricane."

That's about 234mph. My archive has the one for 227mph. There's been some since 2003.

And again, this is a value somewhere in a sonde on the way down. None of these are at the surface.

[sasha_B]

Barely got any sleep watching this....like many on here, I'm sure. The way that Melissa seems to still be deepening on that last center pass, even as the satellite presentation has started to degrade (to "only" an instantaneous T7.7), is remarkable. Looks like she could surpass Erin or even Ragasa at this rate.

[Beef Stew]

Should have this next center fix from AF any minute now.

[GCANE]

 https://x.com/JamaicaObserver/status/1982796809110958390

[chaser1]

Looks like the west motion has stopped, may be doing a small cyclonic loop then start the north drift.

That sounds entirely sensible. Otherwise, I'd be pretty sure that nobody actually has "due south motion" on their Bingo card
One other thought does come to mind though. Given the already weakening steering, might well seeing an additional intensification phase where the increases deepening might be briefly negating the minimal steering conditions in place?

[kevin]

New center pass, 909.5 mb extrapolated pressure.

[zal0phus]

I just woke up to this. Genuinely can't believe what I'm seeing and I hope Kingston is spared. After all it struggled yesterday, I have to wonder what Melissa's true ceiling is now.

[zal0phus]

This season is really odd with now THREE C5s, and everything else not named Erin, Humberto, Gabrielle and Imelda ended up underwhelming, yet were likely to end with above-average ACE. Very weird.

Also that dropsonde is insane and I think is the highest gust (210 kt) measured in a TC in a dropsonde besting out Megi by 1 kt..

Very 1999 or 2007-like in that sense. The overall conditions/storm strength behavior this year were very binary. Storms that didn't have optimal conditions to strengthen greatly struggled, and storms that did massively overperformed.

Either we're in another highly active era as bad as the 20s and 30s, or this is the new standard with increasing oceanic heat. Neither scenario is comforting

[sasha_B]

909.5 hPa is a little lower than the previous minimum extrapolated pressure, but higher than the estimate on the last VDM, so perhaps intensity really has peaked. Will have to wait for dropsonde confirmation, though.

[Teban54]

 https://x.com/JamaicaObserver/status/1982796809110958390

This aspect of the storm is even worse for impacts than wind speed alone. I mean, yeah, a Cat 5 or high-end Cat 4 landfall will always be devastating... But even more so when you already had days of rain saturating the ground and gusts that threaten various structures, not to mention requiring residents to stay indoors for prolonged periods of time while draining their supplies.

NHC has been advising Jamaican residents to "seek shelter now" since 1.5 days ago, and still says this despite another 24 hours until landfall:

Jamaica: Do not venture out of your safe shelter.

Now, the hurricane models from a few days earlier where a Cat 3/4 was basically parked right along the south coast of Jamaica (as opposed to some distance away like right now) would have been even more devastating... But what's happening in reality isn't much better.

[Stormgodess]

 https://x.com/JamaicaObserver/status/1982796809110958390

This aspect of the storm is even worse for impacts than wind speed alone. I mean, yeah, a Cat 5 or high-end Cat 4 landfall will always be devastating... But even more so when you already had days of rain saturating the ground and gusts that threaten various structures, not to mention requiring residents to stay indoors for prolonged periods of time while draining their supplies.

NHC has been advising Jamaican residents to "seek shelter now" since 1.5 days ago, and still says this despite another 24 hours until landfall:

Jamaica: Do not venture out of your safe shelter.

3 hrs ago I was watching a group of live cameras on the island, and the feed had the local radio station playing in the background. There were already several areas on the island that had lost power being reported.

[chaser1]

Just curious but does anyone happen to know where the Island's primary electrical infrastructure/production centers are located? I would assume relative proximity to Kingston but that's just a guess

[Teban54]

SE quad had two reports of 156 kt FL, similar to the last pass. Whether NHC goes with 140 or 145 kt at 11am EDT probably comes down to a judgment call.