2024 Global Model Runs Discussion (Out thru day 16)

[Jr0d]

It is interesting the operational run takes a storm into CA but it appears the majority of the ensembles take it north.

Also interesting that we also see a storm possibly making it that far west in mid to late October.

Ensembles at this range, op will windshield wiper for days like helene and milt.

Not sure how they weight the ensembles for the OP run, but it does seem like the majority ensemble runs prefer the north solution.

Still a "phantom storm" and the OP past 5 days is more or less guessing.

Until we get something to track, I will not give any weight to the OP runs and rely almost exclusively on Ensembles.

That said, the upper air forecast currently looks very favorable fir future development next week.

[underthwx]

Im reading several different news agencies talking about another potential system forming in the Western Carribean in the coming days.....I hope not.....no news will be good news as far as I am concerned.....

[underthwx]

From FOX 35 news..."ORLANDO, Fla. - The FOX 35 Storm Team is monitoring a potential weather system developing in the Caribbean Sea, with a more precise outlook expected in the coming days.

Hurricane Milton's departure is welcome news, with only a small chance of another storm developing over the next week. However, models are hinting at possible activity in the Western Caribbean Sea.

According to the GFS model, a significant cold front is expected to sweep across the eastern U.S. next week, bringing a blast of cooler air down to Central Florida by October 15. The European model is less confident in the development, but the potential remains"........

My question is.....does this next possible system compare to Helene or Milton's developmental stages?.....is this long-tange outlook comparable to these past 2 cyclones?.....I realize it's very premature at this point in time....but it seems similar....considering what has already occurred with Helene and Milton....and I need to be very clear....im not asking if any area of the US can expect more tropical activity....my interest is only on long range forecasts....

[Woofde]

We probably need a lemon sooner than later, this is the GFS at hour 108, 998mb in under 5 days.

[cheezyWXguy]

18z gefs coming in hot…

[USTropics]

We can track the catalyst for the system the GFS is forming. In the NHC 12z analysis, there is a tropical wave currently located in the central Atlantic around 50W. We can also see the monsoonal trough/ITCZ is positioned further south in the Caribbean:

A central Atlantic tropical wave is near 47W from 12N southward,
moving westward at 10-15 kt. Scattered showers are in the vicinity
of the wave axis.

A common area of low-level vorticity development due to the terrain is located near Columbia/Panama (highlighted in teal below). Essentially the orientation of the mountain range and valley in this region provides a topographical lift that assists in low-level vorticity forming here:


The wave will provide some extra 'lift' for the vort streamer in ~72 hours as it becomes tilted, and this interaction is what the GFS has for development:


While the GFS is all alone in its solution, the CMC has been trending towards increased vorticity in this region. The difference is, the lift isn't fully there on the CMC, and it moves across Central America into the EPAC before developing:


This is also a climatological favorable region for development during this time period of October:

[weeniepatrol]

[TomballEd]

GFS and ensembles has a tendency to be too bullish in the SW Caribbean. I'd be more confident if other models start showing support. If this does develop, and 94L stays weak long enough to reach the Caribbean, Florida's season may not be over. Maybe even two threats.

[MarioProtVI]

We can track the catalyst for the system the GFS is forming. In the NHC 12z analysis, there is a tropical wave currently located in the central Atlantic around 50W. We can also see the monsoonal trough/ITCZ is positioned further south in the Caribbean:
https://i.imgur.com/e8rTxKe.png

A central Atlantic tropical wave is near 47W from 12N southward,
moving westward at 10-15 kt. Scattered showers are in the vicinity
of the wave axis.

A common area of low-level vorticity development due to the terrain is located near Columbia/Panama (highlighted in teal below). Essentially the orientation of the mountain range and valley in this region provides a topographical lift that assists in low-level vorticity forming here:
https://i.imgur.com/WR2tHHZ.png

The wave will provide some extra 'lift' for the vort streamer in ~72 hours as it becomes tilted, and this interaction is what the GFS has for development:
https://i.imgur.com/59pW0UK.gif

While the GFS is all alone in its solution, the CMC has been trending towards increased vorticity in this region. The difference is, the lift isn't fully there on the CMC, and it moves across Central America into the EPAC before developing:
https://i.imgur.com/Y4ctGdl.gif

This is also a climatological favorable region for development during this time period of October:
https://www.nhc.noaa.gov/climo/images/oct_11_20.png

Another possible reason Euro isn’t on board is perhaps it sees something we don’t. GFS is known to have a bias in this area especially late season to spin up storms from random vorticity off SA. NHC seems to agree with that..

[USTropics]

We can track the catalyst for the system the GFS is forming. In the NHC 12z analysis, there is a tropical wave currently located in the central Atlantic around 50W. We can also see the monsoonal trough/ITCZ is positioned further south in the Caribbean:
https://i.imgur.com/e8rTxKe.png

A central Atlantic tropical wave is near 47W from 12N southward,
moving westward at 10-15 kt. Scattered showers are in the vicinity
of the wave axis.

A common area of low-level vorticity development due to the terrain is located near Columbia/Panama (highlighted in teal below). Essentially the orientation of the mountain range and valley in this region provides a topographical lift that assists in low-level vorticity forming here:
https://i.imgur.com/WR2tHHZ.png

The wave will provide some extra 'lift' for the vort streamer in ~72 hours as it becomes tilted, and this interaction is what the GFS has for development:
https://i.imgur.com/59pW0UK.gif

While the GFS is all alone in its solution, the CMC has been trending towards increased vorticity in this region. The difference is, the lift isn't fully there on the CMC, and it moves across Central America into the EPAC before developing:
https://i.imgur.com/Y4ctGdl.gif

This is also a climatological favorable region for development during this time period of October:
https://www.nhc.noaa.gov/climo/images/oct_11_20.png

Another possible reason Euro isn’t on board is perhaps it sees something we don’t. GFS is known to have a bias in this area especially late season to spin up storms from random vorticity off SA. NHC seems to agree with that..

I would agree, until we get some more model agreement I don't put a lot weight on the GFS model suite solution on its own. However, I do hold some reserve on this being the usual GFS spurious vorticity bias (it's more common in the NW Caribbean) since we have a tropical wave also providing convergence out in front. The ECMWF does not develop this, but it does have the moisture plume entering the NW Caribbean before being stretched out along a frontal zone:


While chances are low, the GFS solution is plausible and not necessarily from spurious vorticity, and the model did show the possibility of Milton (albeit it was inconsistent) even after all of the other models dropped it.

[ScottNAtlanta]

I have to say, the Euro has not been particularly good with the last 3 GOM systems...by a lot.

[Hypercane_Kyle]

I have to say, the Euro has not been particularly good with the last 3 GOM systems...by a lot.

Yeah, the Euro is unfortunately probably the worst model when it comes to TC genesis. Even the JMA seems to pick them up more often than the Euro does. It's not until the storm is literally on the doorstep of genesis that it starts development. The EC-AIFS, however, does appear to have some skill.

[Fancy1002]

00z is looking interesting.

[Kazmit]

00z GFS has a major hurricane 6 days from now. Wild.

[Category5Kaiju]

GFS shows an Iota-like storm that just bombs out near Central America while headed toward it

[mantis83]

0Z gfs ensembles are further south more in line with the operational, this has little chance of affecting the gulf coast or florida……..good news for sure

[WeatherBoy2000]

Something to keep in mind about the SW Caribbean disturbance:

 https://x.com/AndyHazelton/status/1845071713295335481




 https://x.com/dmorris9661/status/1845073568549232783




Overamplifying these features is a common gfs/gefs bias, the fact that they're largely on their own is a red flag for this being a ghost storm atm. Don't be surprised if nothing happens.

[wxman57]

One thing I see different next week is the movement of a strong cold front all the way south to the NW Caribbean. The jet stream dipping down all the way to the southern Gulf should shut down the potential for hurricane development in the Gulf. It would be more common for something to form in the SW Caribbean that moves west into Central America. Besides, our annual Orlando trip comes up in a week. I will not allow any hurricanes to impact Florida.

[ConvergenceZone]

One thing I see different next week is the movement of a strong cold front all the way south to the NW Caribbean. The jet stream dipping down all the way to the southern Gulf should shut down the potential for hurricane development in the Gulf. It would be more common for something to form in the SW Caribbean that moves west into Central America. Besides, our annual Orlando trip comes up in a week. I will not allow any hurricanes to impact Florida.

Have fun in Orlando WXMAN, and so glad to see the cold front moving into the Carib. It's nice to see the season "slowly" winding down. I would have no problem seeing a few more out to sea storms, but I think everyone is probably burned out on following the tropics at this point anyway lol.

[Teban54]

Something to keep in mind about the SW Caribbean disturbance:

 https://x.com/AndyHazelton/status/1845071713295335481




 https://x.com/dmorris9661/status/1845073568549232783




Overamplifying these features is a common gfs/gefs bias, the fact that they're largely on their own is a red flag for this being a ghost storm atm. Don't be surprised if nothing happens.

At this point it can probably go either way. GFS was also among the first models to sniff out Helene and Milton, even though Milton eventually formed much later and further NW than GFS initially expected. I don't think it has had any phantoms in the Caribbean so far this season.