Tropical Wave East of the Windward Islands (Is Invest 98L)

[zzzh]

The most active Google DM FNV3 run so far.

[Spacecoast]

The most active Google DM FNV3 run so far.

A few more members on 18z.. I counted ~25 members (out of 50 members). Previous DM FNV3 runs had about 18 members out of 50 (36%)

[cycloneye]

The wave looks very good and is not far from being tagged as Invest 98L.

[zzzh]

Almost has a closed circulation

[blp]

The newer version of DeepMind.

[cycloneye]

 https://x.com/NbergWX/status/1979015771582829020

[blp]

Icon has flipped back to tbr Euro Ukmet camp no longer NE pull.

[LarryWx]

Other 0Z:
-GFS remains consistent with recent runs with a H hit on the VIs on 10/24
-CMC again has TCG before the Caribbean and again it turns as a cat 1 H sharply into Hisp., where it weakens a lot. After that the main piece of that in the form of a weak low moves back down SW into the W Car. Similar to the 0Z run of 24 hours ago.
-UKMET still no TCG in the Caribbean, but there’s a 1006 mb sfc low that moves W to 200 miles E of Nicaragua
-Euro TBD

[AJC3]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Fri Oct 17 2025

1. East of the Windward Islands into the Caribbean Sea:
A tropical wave currently located over the central tropical Atlantic
is associated with a large area of showers and thunderstorms. Some
gradual development of this system is possible over the next several
days as it moves westward at 15 to 20 mph. Regardless of
development, heavy rainfall and gusty winds are possible as the
system moves across the Windward Islands late this weekend and
enters the Caribbean Sea by the early to middle part of next week.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

[abajan]

The newer version of DeepMind.

https://i.ibb.co/x8J2RHwn/genc-2025-10-16-18-Z-312-28-686-261-154-10-876-293-223-SST-Anomaly-Surface-tracks-lows.png

Uh huh. That's what thinking too deeply does for yuh.

[chaser1]

This IS a rather murky situation. Here's what leaps out at me regarding the models. The GFS develops this sooner and deeper than the other models however the GFS is also the slower of the models in terms of westward forward motion as a whole. It does appear that a significant short wave is at its zenith on or about 10/24 off the East CONUS Seaboard. That trough in conjunction with a stronger T.S. that is between 65W -70W would appear to decay the mid level ridging to provide a poleward escape route.
On the other hand a broad weak primarily surface reflection might well continue to track further west where better nudged under (or embedded) in a mid level environment of stronger heights. This latter solution would introduce a couple Jokers mixed into the cards and ultimately put a lot more people at some potential jeopardy resulting from a West Caribbean threat.

At this point I think the key is how quickly does it develop AND how far west does the disturbance get prior to development. Sort of like picking an "over/under" for where a T.D. develops (or whether it pulls a 91L instead LOL).

[weeniepatrol]

GDM trend:

[GCANE]

850mb vort appears to be quickly consolidating.

[Cachondo23]

If we do get a Lenny 99’ type system (moving east) is the worst part on the west?

[GCANE]

Current initializations from GFS and Euro appears that Euro is more aligned with the 850mb vort shown in CIMSS

[cycloneye]

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1215 UTC Fri Oct 17 2025

...TROPICAL WAVES...

The axis of a central Atlantic tropical wave is near 40W from 17N
southward, moving westward at around 15 kt. Scattered moderate to
isolated strong convection is noted from 05N to 12N between 36W
and 44W. Some gradual development of this system is possible over
the next several days as it continues westward. Some gradual
development of this system is possible over the next several days
as it moves westward at 15 to 20 mph. Regardless of development,
expect fresh to strong winds and rough seas along with heavy
rainfall and gusty winds with this system.

[abajan]

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1215 UTC Fri Oct 17 2025

...TROPICAL WAVES...

The axis of a central Atlantic tropical wave is near 40W from 17N
southward, moving westward at around 15 kt. Scattered moderate to
isolated strong convection is noted from 05N to 12N between 36W
and 44W. Some gradual development of this system is possible over
the next several days as it continues westward. Some gradual
development of this system is possible over the next several days
as it [moves] westward at 15 to 20 mph. Regardless of development,
expect fresh to strong winds and rough seas along with heavy
rainfall and gusty winds with this system.

Initially, I thought that was inadvertent repetition on your part. But when I checked the text at the source a few minutes ago, I realized the error was theirs and not yours.

[GCANE]

138hrs out and synoptics don't look too different between Euro and GFS ranging from a negative-tilt trof over east CONUS, Surface High over TN, and a surface low around 40N 40W.
355K PV looks good for development.
Biggest difference I see between the two models is that Euro moves this faster west that GFS.
GFS creates a strong front to the north of this at that time which allows the system to pull sharply north while Euro does not create the front.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Fri Oct 17 2025


East of the Windward Islands and the Caribbean Sea:
A tropical wave located over the central tropical Atlantic more than
1000 miles east of the Windward Islands continues to produce a large
area of showers and thunderstorms. Gradual development of this
system is possible over the next several days while it moves
generally westward at 15 to 20 mph. Regardless of development, this
system is expected to bring heavy rainfall and gusty winds to the
Windward Islands late this weekend and then move across the
Caribbean Sea much of next week.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

[GCANE]

138hrs out and synoptics don't look too different between Euro and GFS ranging from a negative-tilt trof over east CONUS, Surface High over TN, and a surface low around 40N 40W.
355K PV looks good for development.
Biggest difference I see between the two models is that Euro moves this faster west that GFS.
GFS creates a strong front to the north of this at that time which allows the system to pull sharply north while Euro does not create the front.

Run-to-run GFS has that front digging in.