Tropical Wave in the West-Central Caribbean (Is Invest 91L)

[LarryWx]

12Z UKMET: once again no Caribbean TC genesis through 144 hours

[Longhornmaniac8]

So if hypothetically one were planning a trip to Cancun this Saturday, one should probably cancel it before the cancellation fee increases if they were looking for nice beach weather Saturday-Wednesday?

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Wed Sep 30 2020

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

A tropical wave located over the west-central Caribbean Sea is
expected to move westward over the next couple of days, and produce
a broad area of low pressure over the western Caribbean Sea by
Thursday night or Friday. Environmental conditions are forecast to
be conducive for some development thereafter, and a tropical
depression could form over the weekend while the system moves slowly
west-northwestward over the northwestern Caribbean Sea.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...60 percent.

$$
Forecaster Pasch

[gatorcane]

Despite decent model agreement this ends up moving into the Yucatan in the next 3-4 days, I noticed the NHC outlook won’t commit to that (yet)

[DestinHurricane]

Despite decent model agreement this ends up moving into the Yucatan in the next 3-4 days, I noticed the NHC outlook won’t commit to that (yet)

NHC>models. Always.

[Loveweather12]

Because the NHC are experts and they understand common sense to know models change and plus a low hasn’t formed yet. Always trust the experts!

Despite decent model agreement this ends up moving into the Yucatan in the next 3-4 days, I noticed the NHC outlook won’t commit to that (yet)

[USTropics]

Because the NHC are experts and they understand common sense to know models change and plus a low hasn’t formed yet. Always trust the experts!

Despite decent model agreement this ends up moving into the Yucatan in the next 3-4 days, I noticed the NHC outlook won’t commit to that (yet)

They will use experience, and these evolutions are always tricky to forecast. More times than not, when you have development along the tail end of a frontal boundary, you will get lowering pressures to the NE. You will often see competing lobes of vorticity, and the NE lobe is typically favored (as the lowest pressure maximum is favored to the NE). You can see in the past few GFS run trends, the model has been trending in that direction. It's not a sure thing, as stated these evolutions are tricky to forecast. But from my experience, that's what I would be looking for (and what the NHC is likely considering as well):

[cheezyWXguy]

Aggregation of vorticity seems to be occurring near 16N 78W, if my eyes don’t deceive me. With a north of west movement, this should clear Honduras

[Emmett_Brown]

Starting to look invest worthy

[Nimbus]

Aggregation of vorticity seems to be occurring near 16N 78W, if my eyes don’t deceive me. With a north of west movement, this should clear Honduras

Lots of lightning strikes which might be near the apex of the wave.
I thought Luis might have locked the thread for the invest by now?

[AutoPenalti]

Aggregation of vorticity seems to be occurring near 16N 78W, if my eyes don’t deceive me. With a north of west movement, this should clear Honduras

Lots of lightning strikes which might be near the apex of the wave.
I thought Luis might have locked the thread for the invest by now?

Give a couple of minutes.

[psyclone]

the tropics are looking....not boring...over the next couple of weeks. stuff is going to happen..

[GeneratorPower]

Has an invest been declared for this?

[eastcoastFL]

Despite decent model agreement this ends up moving into the Yucatan in the next 3-4 days, I noticed the NHC outlook won’t commit to that (yet)

Models are kinda useless without a low. They’re just a tool but not a super helpful one prior to genesis this year. I trust NHC, Gcane and Aric far more than all the models combined.

[northjaxpro]

Has an invest been declared for this?

Not yet

[aspen]

Most of the 850mb-level vorticity associated with this wave is finally over the SW Caribbean Sea and within the huge mass of convection. I believe this is earlier than when most of the models expected the disturbance’s vorticity to be over open water, so either it’ll have more time to develop and intensify, or it’ll get to the Yucatán earlier as well.

[SFLcane]

Hmmm... gfs stays out of BOC this time.

[toad strangler]

Hmmm... gfs stays out of BOC this time.

It'll get there. Moving that way at 120

[SFLcane]

Hmmm... gfs stays out of BOC this time.

It'll get there. Moving that way at 120

That stall near the Yucatán will mean more rain for us in South Florida.

[toad strangler]

Hmmm... gfs stays out of BOC this time.

It'll get there. Moving that way at 120

That stall near the Yucatán will mean more rain for us in South Florida.

Yup, high rain chances moving in for the next week at least. I'll take that without the 120mph winds all day long

Meanwhile the 18z GFS looks like a pinball machine with vorts spinning all over the place