ATL: FRANCINE - Remnants - Discussion

[wx98]

When will we know more info on future track? Thanks

The first advisory will be issued at 21z. Will have a Cat 1 into Lake Charles area on Wednesday night.

[Frank P]

So we now have two LLCs or vorts each with its own robust hot towers... This is gonna be fun.

https://i.postimg.cc/zvd1NCJH/image.png

That PTC will be damn interesting if RECON verifies two centers...

[ElectricStorm]

I guess this might end up getting stronger than I thought it would if the NHC does end up going with a Cat 1 on the initial advisory. Can't ever trust a gulf storm, hopefully it doesn't get any stronger than that.

[wxman57]

I'm thinking PTC Six shortly. Not a well-defined or organized circulation.

[MarioProtVI]

I'm thinking PTC Six shortly. Not a well-defined or organized circulation.

 https://x.com/nhc_atlantic/status/1832877137495494956

[psyclone]

Will hurricane and storm surge watches be issued on advisory 1? My guess is yes. I think a hurricane landfall is more likely than not

[ROCK]

This is going to take a minute to flush out one of these centers…messy set up but props to the ICON. It’s been sitting on this for days now…

[wx98]

Will hurricane and storm surge watches be issued on advisory 1? My guess is yes. I think a hurricane landfall is more likely than not

Watches for Mexico on Adv 1. They’ll prob wait 6 or 12 hours for Texas watches.

[Category5Kaiju]

I'm thinking PTC Six shortly. Not a well-defined or organized circulation.

You saw the future

[Craters]

Those front-related winds are helping to spark the circulation center via shear vorticity. The center will then begin to strengthen the pressure gradient to the southwest as it becomes better defined. So a bit of a chain reaction/positive feedback process taking place with this situation.

ColdMiser, Wxman, et al. -- How much will that shear help (hurt?) in pulling in that dry air to the west? I hate to keep harping on dry air here, but it's a factor that seems to be low on the list of interesting things to talk about. It's saved our bacon before, so I don't want to ignore it.

I don’t think the dry air matters that much because it’s an enhancing wind blowing in the right direction for a circulation forming to its east. Jmo.

RIght, Steve, I got that part, but other posters during other storms have made the point that shear can help the intrusion of dry air into the circulation. I'm not real clear as to why shear is necessary for that, but this looks like it could be that kind of situation, maybe. Soooo, my thinking is that, yes, the winds are in the right direction to help the circulation develop, but would that come at the price of advecting more dry air into the system? I guess if I understood why shear helps in the first place, I wouldn't be asking weird stuff like this. Duh.

[IcyTundra]

They are forecasting a 65 kt hurricane to make landfall near the TX/LA border in 72 hours. Still time for things to change in regards to track and intensity though.

[texsn95]

What could cause this to go a little farther east, more towards the tip of Louisiana?

[IcyTundra]

What could cause this to go a little farther east, more towards the tip of Louisiana?

The stronger it becomes the further east it will go. The 12Z GFS and 12Z Euro both take PTC6 to Vermillion Bay which is currently on the eastern end of model guidance right now which makes sense considering they are the most bullish right now.

[BigB0882]

I'm thinking PTC Six shortly. Not a well-defined or organized circulation.

You seemed pretty bullish on a Vermillion Bay (or just west of there) landfall before. What is your opinion on landfall? Any change? I feel like these storms tend to end up further east than initially forecast, if anything.

[Frank P]

Per the NHC for PTC 6 some interesting comments. "The track guidance this cycle shifted east, with the GFS and ECMWF models notably on the east side of the guidance envelope. The initial NHC track forecast won't go quite that far east but splits the difference between the consensus aid TVCN and these eastward model solutions. FUTURE ADJUSTMENT could be necessary if these EASTWARD TRENDS CONTINUE. Given the current structure, the track forecast is of LOWER CONFIDENCE than usual." Track errors 4 day out are 125 miles

[Steve]

ColdMiser, Wxman, et al. -- How much will that shear help (hurt?) in pulling in that dry air to the west? I hate to keep harping on dry air here, but it's a factor that seems to be low on the list of interesting things to talk about. It's saved our bacon before, so I don't want to ignore it.

I don’t think the dry air matters that much because it’s an enhancing wind blowing in the right direction for a circulation forming to its east. Jmo.

RIght, Steve, I got that part, but other posters during other storms have made the point that shear can help the intrusion of dry air into the circulation. I'm not real clear as to why shear is necessary for that, but this looks like it could be that kind of situation, maybe. Soooo, my thinking is that, yes, the winds are in the right direction to help the circulation develop, but would that come at the price of advecting more dry air into the system? I guess if I understood why shear helps in the first place, I wouldn't be asking weird stuff like this. Duh.

In this case it’s not organized yet so the strong winds coming around that already curved coast will just help with the counterclockwise flow on the western and southwestern side around what will be an organizing center. So these winds are favorable to the low pressure as they are blowing in a direction that would be the same on the west side of a low pressure (out of NW/NNW/N

[Teban54]

Per the NHC for PTC 6 some interesting comments. "The track guidance this cycle shifted east, with the GFS and ECMWF models notably on the east side of the guidance envelope. The initial NHC track forecast won't go quite that far east but splits the difference between the consensus aid TVCN and these eastward model solutions. FUTURE ADJUSTMENT could be necessary if these EASTWARD TRENDS CONTINUE. Given the current structure, the track forecast is of LOWER CONFIDENCE than usual." Track errors 4 day out are 125 miles

This is also a good time for reminders about the NHC forecast cone: (Hopefully long-term users are familiar with this, but many guests are probably watching)

• The cone only shows historical variations of an average storm. Its size is the same for every single storm, so it speaks nothing about track confidence for PTC 6 in particular.
• Even the cone only shows 67% confidence: that is, historically any storm has a two-thirds chance of falling inside the cone. This means there's still a 1-in-3 chance of falling outside the cone for an average forecast, much less one with below-average confidence like PTC 6.

[underthwx]

They are forecasting a 65 kt hurricane to make landfall near the TX/LA border in 72 hours. Still time for things to change in regards to track and intensity though.

The NHC eluded to the uncertainty of track and intensity during this 1st advisory ...so stay tuned....like always...

[Woofde]

Does anyone know if this is a GOES East problem or is it tropical tidbits? Very bad timing if the former.

[sphelps8681]

When is the next advisory. I am in SE Tx.