NATL: MELISSA - Hurricane - Discussion

[Stormgodess]

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

Jamaica's electrical power stations include a mix of oil-fired plants, a growing number of gas-fired facilities, and several hydroelectric plants, operated by both the national utility, Jamaica Public Service (JPS), and independent power producers (IPPs). Major facilities include the Bogue Power Station, which is being modernized to use natural gas, the Old Harbour Power Station, and several power barges.

Key power stations
Bogue Power Station: Located in Montego Bay, this is one of Jamaica's main power plants. It is currently being repowered with a gas turbine to improve efficiency and incorporate natural gas into the energy mix, reports GE Vernova.

Old Harbour Power Station: Also known as the South Jamaica Power Centre, this facility is a large operating power plant in Old Harbour Bay.

Hunts Bay Power Plant: Located in Kingston, this is a significant power-generating facility operated by JPS, according to the Open Infrastructure Map.

Jamalco Power Plant: An IPP facility in Clarendon, with a capacity of 150 MW.

Rockfort Private Power Station: Also known as the Jamaica Private Power Company, this is another IPP facility with a 60 MW capacity.

Doctor Bird Power Plant: Operated by Jamaica Energy Partners (JEP), this includes power barges located in Old Harbour Bay.

[Jr0d]

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.

.............snip........
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-

While the Katrina reading is off the charts, what I find more impressive about this latest dropsonde from Melissa(if it is verified) is not only it was at the 907mb pressure height vs the 866mb pressure height in Katrina, but it also detected a big column of winds over 175 kts that extended close to the surface.

[InfernoFlameCat]

Nhc went with 165mph and 908 mb

[kevin]

BULLETIN
Hurricane Melissa Advisory Number 25
NWS National Hurricane Center Miami FL AL132025
1100 AM EDT Mon Oct 27 2025

...CATEGORY 5 MELISSA EXPECTED TO TURN NORTHWARD LATER TODAY OR
TONIGHT...
...CATASTROPHIC AND LIFE-THREATENING WINDS, FLOODING, AND STORM
SURGE EXPECTED ON JAMAICA TONIGHT AND EARLY TUESDAY...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.4N 78.2W
ABOUT 145 MI...230 KM SW OF KINGSTON JAMAICA
ABOUT 330 MI...530 KM SW OF GUANTANAMO CUBA
MAXIMUM SUSTAINED WINDS...165 MPH...270 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 3 MPH...6 KM/H
MINIMUM CENTRAL PRESSURE...908 MB...26.82 INCHES

[Travorum]

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

https://en.wikipedia.org/wiki/List_of_power_stations_in_Jamaica

I found this list for production, It looks like by capacity most production infrastructure is located in the two parishes to the west of Kingston (St Catherine and Clarendon), with some capacity in Kingston itself. There are also a few notable production facilities up near Montego Bay. There are several wind farms and a hydroelectric plant near where Melissa is more likely to make landfall in St Elizabeth parish, they produce a little over 100MW combined.

[kevin]

With a peak intensity of 908 mb, Melissa has now passed 1924 Cuba, Ivan and Dorian. It is now tied with Maria as the 11th most intense Atlantic hurricane in the database.

[ATDoel]

Does anyone know how the NHC got to 908 mb? None of the drops were even close to that (912 mb on the last) and even extrap didn't get quite that low.

[kevin]

Does anyone know how the NHC got to 908 mb? None of the drops were even close to that (912 mb on the last) and even extrap didn't get quite that low.

The last dropsonde has 912 mb with 36 kt surface wind, which translates to 908 - 909 mb.

[Teban54]

With a peak intensity of 908 mb, Melissa has now passed 1924 Cuba, Ivan and Dorian. It is now tied with Maria as the 11th most intense Atlantic hurricane in the database.

If Melissa can deepen by another 3 mb, it would tie with Mitch and Dean as the 9th most intense Atlantic hurricane on record at 905 mb. It would also tie with Ragasa as the most intense tropical cyclone in 2025 (by official records).

Of course, the feasibility of further deepening is another question.

[sasha_B]

145 kts means that this has officially surpassed Ragasa (and Humberto/Erin/Errol) in maximum sustained winds. 908 hPa also makes it the second-most-intense storm globally in 2025. Knowing that Ragasa was likely sub-900 and at or above 145 kt itself makes this feat slightly less impressive....but only slightly. For the Atlantic, this is just about top-tier - the peak Dvorak presentation alone was a record-setter.

[Hurricane2022]

What a complicated day it has been for me so far. I almost overslept, barely had time to grab my phone and check what was happening, I just sent a good morning message to my family. During my lunch break, I finally got to see what was happening and I was shocked. Unbelievable!

[mrbagyo]

AF plane headed up north, looks like it's going for another pass

[Flwxguy86]

is it possible the models are thinking the ridge is weaker than it really is? this movement west seems like more than a wobble or a jog. It so far showing no hint of moving even wnw let alone NW or NE..not saying it won't but in about 12-24 hours, it will either barely clip the islands west coast or miss it all together..my concern right now wouldn't be necessarily what happens next, but the trust that would be eroded away if it does miss Jamaica or just barely clips the western edge after being told for days it would effect the entire island, Kingston is damn near in the clear as far as the eye at this point, its almost due south of kingston by 100 miles or so..I guess we will know by tonight, but I am not liking the trend west, although its great for most of jamaica except the constant rain and flooding but I think it may be far enough south that the flooding may not be as catastrophic as predicted. Let's hope thats turns out to be the case.

[Hurricane2022]

 https://x.com/CIRA_CSU/status/1982813591158857799

[Teban54]

145 kts means that this has officially surpassed Ragasa (and Humberto/Erin/Errol) in maximum sustained winds. 908 hPa also makes it the second-most-intense storm globally in 2025. Knowing that Ragasa was likely sub-900 and at or above 145 kt itself makes this feat slightly less impressive....but only slightly. For the Atlantic, this is just about top-tier - the peak Dvorak presentation alone was a record-setter.

Hmm, most records that I can find now show that JTWC did have a 1-min wind speed of 145 kt for Ragasa. (I can't open their website, so showing CSU here.) Was this another case of JTWC's silent best track revisions? Or were you converting JMA to 1-min?

[kevin]

Interpolating the current NHC forecast for Melissa means that we'd get about 17.2 more ACE from this storm from now on. Added to the current 112.6 ACE value for the season would bring the total ACE for 2025 to roughly 130.

[ATDoel]

With a peak intensity of 908 mb, Melissa has now passed 1924 Cuba, Ivan and Dorian. It is now tied with Maria as the 11th most intense Atlantic hurricane in the database.

If Melissa can deepen by another 3 mb, it would tie with Mitch and Dean as the 9th most intense Atlantic hurricane on record at 905 mb. It would also tie with Ragasa as the most intense tropical cyclone in 2025 (by official records).

Of course, the feasibility of further deepening is another question.

Is there more shear forecasted? There's high enough STP where Melissa is to get deeper, quite a bit deeper actually.

[sasha_B]

I didn't even realise there had been a subjective Dvorak fix at 12z of T7.5....certainly wasn't expecting that. Glad to see that the values on ADT got some backup from OSPO.

[aspen]

145 kts means that this has officially surpassed Ragasa (and Humberto/Erin/Errol) in maximum sustained winds. 908 hPa also makes it the second-most-intense storm globally in 2025. Knowing that Ragasa was likely sub-900 and at or above 145 kt itself makes this feat slightly less impressive....but only slightly. For the Atlantic, this is just about top-tier - the peak Dvorak presentation alone was a record-setter.

I missed that insane Dvorak presentation overnight. Is this the first time ever that a system managed to hit T8.0 on ADT? Aside from Eta hitting T8.0+ RAWs.

[sasha_B]

145 kts means that this has officially surpassed Ragasa (and Humberto/Erin/Errol) in maximum sustained winds. 908 hPa also makes it the second-most-intense storm globally in 2025. Knowing that Ragasa was likely sub-900 and at or above 145 kt itself makes this feat slightly less impressive....but only slightly. For the Atlantic, this is just about top-tier - the peak Dvorak presentation alone was a record-setter.

Hmm, most records that I can find now show that JTWC did have a 1-min wind speed of 145 kt for Ragasa. (I can't open their website, so showing CSU here.) Was this another case of JTWC's silent best track revisions? Or were you converting JMA to 1-min?

https://i.imgur.com/2bWtHVi.png

Oh, no, you're right! That's odd, I must have misremembered the JTWC peak. Thanks for pointing that out - looks like Melissa has indeed only tied Ragasa for MSW after all.