Broad area of disturbed weather in the Western Caribbean Sea (Is INVEST 91L)

[toad strangler]

NAVY!

[toad strangler]

Euro doesn't even show a low at 850 mb at 216

The Euro’s lack of strengthening makes sense to me as it is handling the high shear correctly unlike the FV3. Anyone disagree?

Tidbits doesn't show Euro shear maps. I assume they are screaming like the GFS?

[AJC3]

An important feature that I haven't seen discussed in this thread yet, and one I think will play a key role in the eventual strength and track of this system is the energy that rotates southward around the western side of Leslie. This trough gets left behind, well east of the Bahamas, on Friday as Leslie gets kicked out to the NE. The trough (or weakly closed mid-upper low) then gets trapped beneath the strong eastern CONUS/western Atlantic ridge to its north and retrogrades W-WSW this weekend. This creates a fairly substantial weakness of some sort to the north and northeast of whatever does develop over the western Caribbean, which would likely impact where and how fast the system eventually moves

Additionally, it also could create some unfavorable shear conditions, especially if it's centered to the N-NE of the Caribbean "mess" (per the slower retrogression of the 12Z OP-GFS. The faster retrogression shown by the 12Z OP-ECM places this trough to the N-NW, which would likely be a little less hostile (more of divergent shear).

In any event, it would probably be a good idea to keep tabs on this feature in the models over the upcoming week.

Here are some model comparisions from 120hr through 168hr. Because of the coarse (60M) resolution of these panels, they really don't give you a good feel at all when it comes to the position and especially the strength/orientation of this trough. If these panels were 10M resolution, it would be much, much better...

120hr


144hr


168hr


192hr (NAVGEM only goes out to 180hr)

[ronjon]

From Bob Henson's blog at weather underground this morning:

Time to watch the Caribbean for development
It’s October, a time of year when the western and central Caribbean Sea typically becomes the Atlantic’s most dangerous breeding ground for hurricanes. So far in 2018, the Caribbean has seen high wind shear and limited hurricane activity due to the presence of a strong subtropical jet stream. However, this may change early next week, when the subtropical jet stream is predicted to lift to the north so that it is positioned over Cuba. This will create a region of lower wind shear over the central and western Caribbean, and recent runs of the GFS and European model have been suggesting that a large area of low pressure will form there this weekend. This low will have the potential to develop into a tropical depression early next week, as predicted by over 30% of the 70 ensemble members of the 0Z Monday GFS and European models. The track such a storm might take is anyone’s guess at this point, and we’ll just have to watch how the models depict the evolution of this potential threat in coming days.

[TheStormExpert]

Very plausible track if you asked me with that massive ridge overhead.

https://www.imageupload.co.uk/images/2018/10/01/yep.gif

Track plausible, strength not so much.

Conditions north of cuba in the bahamas would be favorable so if there is any development down in the carribean look out.

The FV3-GFS has been just as bad, if not worse than the current GFS. Still remember the phantom-cane it had in the Gulf I believe back in late-May or early-June.

[SFLcane]

An important feature that I haven't seen discussed in this thread yet, and one I think will play a key role in the eventual strength and track of this system is the energy that rotates southward around the western side of Leslie. This trough gets left behind, well east of the Bahamas, on Friday as Leslie gets kicked out to the NE. The trough (or weakly closed mid-upper low) then gets trapped beneath the strong eastern CONUS/western Atlantic ridge to its north and retrogrades W-WSW this weekend. This creates a fairly substantial weakness of some sort to the north and northeast of whatever does develop over the western Caribbean, which would likely impact where and how fast the system eventually moves

Additionally, it also could create some unfavorable shear conditions, especially if it's centered to the N-NE of the Caribbean "mess" (per the slower retrogression of the 12Z OP-GFS. The faster retrogression shown by the 12Z OP-ECM places this trough to the N-NW, which would likely be a little less hostile (more of divergent shear).

In any event, it would probably be a good idea to keep tabs on this feature in the models over the upcoming week.

Thank you for this AJC3

[floridasun78]

now we wait see nhc pick it up likely wont until late tue ot wed

[LarryWx]

Euro doesn't even show a low at 850 mb at 216

The Euro’s lack of strengthening makes sense to me as it is handling the high shear correctly unlike the FV3. Anyone disagree?

Tidbits doesn't show Euro shear maps. I assume they are screaming like the GFS?

Yes until the low gets to off the E coast, when shear drops a lot. While in FL straits, it is 30-40 dropping to 20-30 knots overhead!

['CaneFreak]

Low level vorticity was increasing earlier this morning and now has diminished and split apart again. Going to be a lot of sitting and waiting for the next several days.

[ronjon]

NCEP 12z ensemble probabilties of tropical cyclone formation are near 100% in the SW caribbean sea over the next 120 hours.

http://www.emc.ncep.noaa.gov/gmb/tpm/emchurr/tcgen/

[ronjon]

Track plausible, strength not so much.

Conditions north of cuba in the bahamas would be favorable so if there is any development down in the carribean look out.

The FV3-GFS has been just as bad, if not worse than the current GFS. Still remember the phantom-cane it had in the Gulf I believe back in late-May or early-June.

Actually the FV3-GFS performed the best of the models during Florence - on par or even better than the ECM. I wouldn't discount it as its a vast improvement over the current GFS.

[LarryWx]

Conditions north of cuba in the bahamas would be favorable so if there is any development down in the carribean look out.

The FV3-GFS has been just as bad, if not worse than the current GFS. Still remember the phantom-cane it had in the Gulf I believe back in late-May or early-June.

Actually the FV3-GFS performed the best of the models during Florence - on par or even better than the ECM. I wouldn't discount it as its a vast improvement over the current GFS.

Strengthwise too? Did it weaken her to a cat 1 before landfall?

[gatorcane]

Track plausible, strength not so much.

Conditions north of cuba in the bahamas would be favorable so if there is any development down in the carribean look out.

The FV3-GFS has been just as bad, if not worse than the current GFS. Still remember the phantom-cane it had in the Gulf I believe back in late-May or early-June.

I would think they have been tweaking the model periodically so it is probably better now than several months ago.

[LarryWx]

We're lucky to have El Nino upping shear overall. That should lower the chance for anything too strong if it were to come off the ATL into FL/SE vs how it would have been w/o Nino. However, climo is a tool and isn't about absolutes. There are always exceptions, including where a TC finds a slot of low shear. Case in point: the early Oct major H that slammed S FL from the E 10/6/1941 during El Nino:

https://www.nhc.noaa.gov/data/tracks/tracks-at-1941.png

[SFLcane]

12z EPS has about 5 hurricanes surrounding FL so still rather active.

[toad strangler]

12z EPS has about 5 hurricanes surrounding FL so still rather active.

All at once?

[LarryWx]

12z EPS has about 5 hurricanes surrounding FL so still rather active.

All at once?

Besides 2 E coast scrapers, I counted 5 H hits on FL, all Big Bend to Sarasota. 3 on 10/11 and 2 on 10/16.

[SoupBone]

12z EPS has about 5 hurricanes surrounding FL so still rather active.

All at once?

Besides 2 E coast scrapers, I counted 5 H hits on FL, all Big Bend to Sarasota. 3 on 10/11 and 2 on 10/16.

It's like machine gun rapid fire hurricanes!

[stormlover2013]

Still don't think anything major, looks wet that's about it, CMC, NAVY, ICON are the ones going over board about it and we know what happens when they do lol meaning those models aren't good so can't trust them long term

[LarryWx]

Are there any models beside Euro, GFS, UK that we can trust won't overstrengthen in high shear?