EPAC: JULIA - Models

[Teban54]

Here's the 0z GFS run. If you look closely, it breaks the vorticity associated with 91L into two starting at 24-30 hrs. Both halves traverse through the Caribbean and start to develop.

While GFS may be overhyping the trailing system, it's not entirely a CAG phantom either. We'll see what happens in 30 hours.

[skyline385]

You’re right, it’s not 91L that the gfs spins up into a major, but that area doesn’t originate from the cag. Watch the 850mb vorticity and you’ll see that some trailing vorticity splits off after it passes the lesser Antilles. GEFS shows something similar, with members starting to pop up in the east-central Caribbean. Icon shows a hint of this too. There could be something to this, but we need more continuity.

Another note, just because the gfs has a notorious cag bias doesn’t mean it will always be wrong when it shows it. Climatologically, we are getting to the time of year where a cag scenario is actually plausible. Again, not the scenario the gfs is showing at the moment, but even if it were a broken clock is still right twice a day.

ICON's genesis is from the actual 91L, GFS builds up spurious vorticity from SA and builds the second system. The 850mb vorticity plot also looks like a classic GFS certified solution with two systems extremely close to each other.

https://i.imgur.com/0FQoqT0.png

https://twitter.com/AndyHazelton/status/1577061136708403200?s=20&t=bhoXSc2KPjnUrHLXCuJjhw

Again, it could be spurious (hence “need more continuity” but it’s not from SA or the CAG.




ICON does develop 91L but shows a hint of the trailing system too, though it’s harder to tell if it comes off of SA when only looking at 500mb

TT’s colors makes it hard to see but here is the trailing vorticity being amplified by spurious vorticity over SA.



Also regarding the ICON, that plot is Z500 which would basically be the MLC. You can get a weak MLC going very easily but that doesn’t translate to a low level circulation. Here’s the actual Z850 on the ICON, no trailing vorticity here.

[Teban54]

Somewhat good support on the 12z and 18z Euro ensembles:

[REDHurricane]

ICON's genesis is from the actual 91L, GFS builds up spurious vorticity from SA and builds the second system. The 850mb vorticity plot also looks like a classic GFS certified solution with two systems extremely close to each other.

https://i.imgur.com/0FQoqT0.png

https://twitter.com/AndyHazelton/status/1577061136708403200?s=20&t=bhoXSc2KPjnUrHLXCuJjhw

Again, it could be spurious (hence “need more continuity” but it’s not from SA or the CAG.

[url]https://i.ibb.co/YkPTRvK/5-F8-CDC22-DA76-4-FD8-8739-2-CE45-E93-B083.jpg [/url]


ICON does develop 91L but shows a hint of the trailing system too, though it’s harder to tell if it comes off of SA when only looking at 500mb

[url]https://i.ibb.co/64YY12f/78716954-F67-C-4-DCB-B39-A-20784-E947467.jpg [/url]

TT’s colors makes it hard to see but here is the trailing vorticity being amplified by spurious vorticity over SA.

https://uploads.tapatalk-cdn.com/20221004/9839026d3d35c22d508c52d8e1495fbb.jpg

Also regarding the ICON, that plot is Z500 which would basically be the MLC. You can get a weak MLC going very easily but that doesn’t translate to a low level circulation. Here’s the actual Z850 on the ICON, no trailing vorticity here.

https://uploads.tapatalk-cdn.com/20221004/153f649d7056af7dc1ab7a40133de1ed.jpg

Agreed, even if there may be some sort of MLC or other energy trailing behind the main part, there's no way it is going to instantaneously amplify like that unless you're in GFS fantasy wonderland. My approximated GFS CAG bias zone for this season reaches just far enough east that it encompasses the tiny trailing piece of energy right as it transforms into another specialty GFS phantom hurricane. I'm far from an expert on this so take my opinion with a sizable grain of salt as always, but everything I do know tells me that it just don't work like that.

[cheezyWXguy]

Again, it could be spurious (hence “need more continuity” but it’s not from SA or the CAG.

[url]https://i.ibb.co/YkPTRvK/5-F8-CDC22-DA76-4-FD8-8739-2-CE45-E93-B083.jpg [/url]


ICON does develop 91L but shows a hint of the trailing system too, though it’s harder to tell if it comes off of SA when only looking at 500mb

[url]https://i.ibb.co/64YY12f/78716954-F67-C-4-DCB-B39-A-20784-E947467.jpg [/url]

TT’s colors makes it hard to see but here is the trailing vorticity being amplified by spurious vorticity over SA.

https://uploads.tapatalk-cdn.com/20221004/9839026d3d35c22d508c52d8e1495fbb.jpg

Also regarding the ICON, that plot is Z500 which would basically be the MLC. You can get a weak MLC going very easily but that doesn’t translate to a low level circulation. Here’s the actual Z850 on the ICON, no trailing vorticity here.

https://uploads.tapatalk-cdn.com/20221004/153f649d7056af7dc1ab7a40133de1ed.jpg

Agreed, even if there may be some sort of MLC or other energy trailing behind the main part, there's no way it is going to instantaneously amplify like that unless you're in GFS fantasy wonderland. My approximated GFS CAG bias zone for this season reaches just far enough east that it encompasses the tiny trailing piece of energy right as it transforms into another specialty GFS phantom hurricane. I'm far from an expert on this so take my opinion with a sizable grain of salt as always, but everything I do know tells me that it just don't work like that

https://i.ibb.co/L8hXr0Z/gfs-z850-vort-atl-27.png

MLC or not, the purpose of that statement was to make the point that a model other than the gfs shows a hint of this. It also originates east of the region you circled. SA or 91L split, spurious or not, it’s not the Central American gyre. I feel like y’all are reading a bit too much into my posts, because I’m not saying at all that the gfs solution is credible. Only that it’s not “cag bias”, and shouldn’t be written off as such.

@skyline, I don’t have a subscription to weathermodels, but on TT the vorticity present in the image I posted (hour 138) has nearly dissipated by the time of your image (hour 159), so it doesn’t really capture what I was getting at

[Teban54]

[cycloneye]

There is much more consensus now.

[cycloneye]

06z GFS is much more bullish. This is not another piece of energy from SouthAmerica, is from 91L.

[Iceresistance]

06z GFS is much more bullish. This is not another piece of energy from South America, is from 91L.

https://i.imgur.com/KD04o4r.gif

If I'm correct, 91L will become another Caribbean monster if it manages to survive the ULL shear into the Caribbean?

EDIT: Just saw the run, it's a Belize Blitzer.

[jlauderdal]

06z GFS is much more bullish. This is not another piece of energy from South America, is from 91L.

https://i.imgur.com/KD04o4r.gif

If I'm correct, 91L will become another Caribbean monster if it manages to survive the ULL shear into the Caribbean?

EDIT: Just saw the run, it's a Belize Blitzer.

Tricky part of the basin for development, needs more model support to say it will be a major, problem with this area is regardless of strength, it's all about the rain in CA, and the mountains are very efficient at squeezing out impressive totals.

[skyline385]

The trough strength and location is still in flux, a stronger or deeper one would allow 91L into the Gulf.


Sent from my LM-V405 using Tapatalk

[LarryWx]

Somewhat good support on the 12z and 18z Euro ensembles:
https://i.postimg.cc/Dz7H7JqB/ecens-2022-10-03-12-Z-240-50-258-0-350-MSLP-Surface-tracks.png
https://i.postimg.cc/QNRXhmVm/ecens-2022-10-03-18-Z-144-50-258-0-350-MSLP-Surface-tracks.png

This support has grown with each of the last 3 EPS runs with the 6Z EPS the most active yet of recent runs.

[ScottNAtlanta]

Intensity models are a lot more bullish than yesterday

[aspen]

12z GFS develops this, but it has a complicated interaction with that magical piece of vorticity it always produces in the SWCar. The GFS is probably going to suck with 91L until we have an organized TS and it gets close enough in time where it doesn’t produce any phantom vorts.

[LarryWx]

In addition to the 12Z GFS being its strongest yet as of hour 144 and the 12Z ICON being its strongest yet along with another hurricane on the 12Z CMC, the 12Z UKMET is its first run with TCG from this (at hour 138 E of Nicaragua moving W):

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 138 HOURS
FORECAST POSITION AT T+138 : 12.8N 80.8W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 10.10.2022 144 12.8N 81.8W 1006 27

[SouthFLTropics]

Based on everything we are seeing I think that 91L is a shoe in for a Central America strike. With regard to any potential CONUS impacts, I think we will need to watch future model runs to see what the remnants do after and/or if it emerges back into the Bay of Campeche. The setup seems to be very much like Mitch 1998. Mitch did eventually emerge in the BOC and reform into a tropical storm before scooting ENE and crossing Florida. At least for the next 10 days, I think the GOM and Florida are closed for business. High pressure in control and beautiful weather here in South Florida today. Forecast looks good into next week.

[gatorcane]

While a track into Central America seems to be the most likely outcome, the latest GEFS leaves some doubt with ridging breaking down over the Gulf and Florida faster than the 06Z. Regardless looks to be a lot of shear blanketing the Gulf anyway:

[SFLcane]

Based on everything we are seeing I think that 91L is a shoe in for a Central America strike. With regard to any potential CONUS impacts, I think we will need to watch future model runs to see what the remnants do after and/or if it emerges back into the Bay of Campeche. The setup seems to be very much like Mitch 1998. Mitch did eventually emerge in the BOC and reform into a tropical storm before scooting ENE and crossing Florida. At least for the next 10 days, I think the GOM and Florida are closed for business. High pressure in control and beautiful weather here in South Florida today. Forecast looks good into next week.

ST jet fully entrenched seems likely the Conus season is just about over.

[mantis83]

Based on everything we are seeing I think that 91L is a shoe in for a Central America strike. With regard to any potential CONUS impacts, I think we will need to watch future model runs to see what the remnants do after and/or if it emerges back into the Bay of Campeche. The setup seems to be very much like Mitch 1998. Mitch did eventually emerge in the BOC and reform into a tropical storm before scooting ENE and crossing Florida. At least for the next 10 days, I think the GOM and Florida are closed for business. High pressure in control and beautiful weather here in South Florida today. Forecast looks good into next week.

ST jet fully entrenched seems likely the Conus season is just about over.

https://i.postimg.cc/xdQQfLb3/gfs.png

agreed.....see ya next year!

[InfernoFlameCat]

Based on everything we are seeing I think that 91L is a shoe in for a Central America strike. With regard to any potential CONUS impacts, I think we will need to watch future model runs to see what the remnants do after and/or if it emerges back into the Bay of Campeche. The setup seems to be very much like Mitch 1998. Mitch did eventually emerge in the BOC and reform into a tropical storm before scooting ENE and crossing Florida. At least for the next 10 days, I think the GOM and Florida are closed for business. High pressure in control and beautiful weather here in South Florida today. Forecast looks good into next week.

ST jet fully entrenched seems likely the Conus season is just about over.

https://i.postimg.cc/xdQQfLb3/gfs.png

Famous last words? It didn't stop Wilma from smacking through it late October.