NATL: MELISSA - Tropical Storm - Discussion

[Hurricane2022]

6z Best Track:

AL, 98, 2025102106, , BEST, 0, 140N, 698W, 40, 1004, DB

This seems to be somewhat ahead of expectations. It appears that we may indeed be facing a strong Hurricane Melissa slowly approaching Hispaniola. That would be a major victory for the GFS, but at the same time, a historic catastrophe for Haiti and the Dominican Republic. But let's just wait and see what happens next.

[cycloneye]

I think Melissa may be introduced before the plane goes this afternoon. Looks like a closed circulation on the edge of convection. First visible will do the trigger.

[kevin]

Virtually absent dry air as well as a very warm region with an MPI below 900mb and above 170kt. Shear is still very high and I honestly expected it to keep 98L in check for a while, but it seems to be doing quite well so who knows.

[cycloneye]

 https://x.com/JimCantore/status/1980553266585866417

[tropicwatch]

98L appears to have a surface circulation this morning.

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-72.43,13.45,3803

[GCANE]

Obviously, a very strong west to east jet is hitting this and GFS is completely ignoring it.
Constant convection indicates a very strong wave or perhaps closed circulation,
IMHO, can pretty much throw out what the models are forecasting at this point.

[BobHarlem]

98L appears to have a surface circulation this morning.

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-72.43,13.45,3803

Still elongated axis sw (From around Siapana in Venezuela) to the north where the top curve is, but it looks like it'll develop in a bit -- it's on it's way. It'll be a judgement call to do so before recon. (Personally I'd wait for recon because of how sensitive to details the models are right now). West of the Lightning cluster area north of Aruba is likely where it'll wind up though. Models do not have a great grasp of the setup right now. Even with development you may have an exposed center at times.



Curaçao radar


https://www.meteo.cw/rad_loop_ppi.php?L ... CC&Sws=R11

[GCANE]

I think Euro is more realistic given the strong shear at this time.
Interesting that Euro run-to-run is showing a more west track in the Caribbean before crossing Cuba.

[GCANE]

May see a drop in convection today as it gets cut off from the Amazon moisture due to the mountains in South America,
Could refire tomorrow or the next day as it connects to the EPAC moisture thru Panama.

[tropicwatch]

May see a drop in convection today as it gets cut off from the Amazon moisture due to the mountains in South America,
Could refire tomorrow or the next day as it connects to the EPAC moisture thru Panama.

Surprised how good it looks with all the wind shear. Pressure is falling, ship reporting 1005mb.

[NDG]

 https://x.com/NDGMETCHEF/status/1980594966754677042

[NDG]

98L appears to have a surface circulation this morning.

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-72.43,13.45,3803

Still elongated axis sw (From around Siapana in Venezuela) to the north where the top curve is, but it looks like it'll develop in a bit -- it's on it's way. It'll be a judgement call to do so before recon. (Personally I'd wait for recon because of how sensitive to details the models are right now). Lightning cluster area north of Aruba is likely where it'll wind up though. Models do not have a great grasp of the setup right now.

https://i.postimg.cc/zXWk35Mw/44359327.gif

Curaçao radar
https://i.imgur.com/WKh54ZH.png

https://www.meteo.cw/rad_loop_ppi.php?L ... CC&Sws=R11

I see hints on your posted satellite loop of SW to NE moving low clouds where I think an LLC is or has just formed in the past few hours, west of the deep convection. IMO.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Tue Oct 21 2025

For the North Atlantic...Caribbean Sea and the Gulf of America:

Caribbean Sea (AL98):
Satellite, radar, and surface observations indicate that the area
of low pressure over the central Caribbean Sea appears to be
developing a well-defined center, and is already producing winds up
to 45 mph. A tropical storm is expected to form later today while
it slows down over the central Caribbean Sea. Heavy rainfall and
gusty winds are possible over portions of the ABC Islands during the
next day or two. Interests in Puerto Rico, Hispaniola, Jamaica, and
Cuba should monitor the progress of this system as there is a risk
of heavy rain and flooding, strong winds, and rough surf later this
week. The Air Force Hurricane Hunters are scheduled to investigate
the system later today. For additional information on this system,
including Gale Warnings, please see High Seas Forecasts issued by
the National Weather Service.
* Formation chance through 48 hours...high...near 100 percent.
* Formation chance through 7 days...high...near 100 percent.

&&
High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFAT1, WMO header FZNT01
KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Cangialosi

[Category5Kaiju]

Looks like Melissa is imminent.

[NDG]

I have the LLC near 14.1N & 71.3W

[jlauderdal]

May see a drop in convection today as it gets cut off from the Amazon moisture due to the mountains in South America,
Could refire tomorrow or the next day as it connects to the EPAC moisture thru Panama.

Would really like to know what is happening at the surface, seen too many really good looking IR presentations and even visible with no LLC, just a sharp trough. This one is a go.

[NDG]

Closed circulation is very evident so far on the first few frames of visible satellite.

 https://x.com/NDGMETCHEF/status/1980609319444918590

[LarryWx]

Closed circulation is very evident so far on the first few frames of visible satellite.

 https://x.com/NDGMETCHEF/status/1980609319444918590

If your coordinates are accurate, that would mean that the 6Z GFS hour 6 position of ~14.2N, 70.4W is ~50 miles too far east and is closer to the rest of the major models.

[GCANE]

The jet is relentless

https://tropic.ssec.wisc.edu/real-time/ ... wg8shr.GIF

Might see a half-naked or full-on naked swirl later in the day.

[GCANE]

Quick look at core showing a slight warm structure but minimal lapse rate.
Since there will be a cutoff in infeed today, not expecting much until this gets to about 75W.

https://rammb-data.cira.colostate.edu/t ... 4_tano.gif