ATL: IDA - Remnants - Discussion

[dantonlsu]

https://imgur.com/FqHb0ry

She's starting to look decent.

[Tireman4]

These will be interesting days ahead. As these next days start to roll on by, remember, this may change from model run to model run. There are amazing pro and amateur Mets on this board and we thank them for coming in and taking the time to spend with us. They will answer your questions, but remember, they are busy too. If you do not get an answer right away, please be patient. Also, take this time ( as always during Hurricane season), to go over your plans and have your kits stocked and ready to go. Double and triple-check your supplies. This is always a good motto to have, whether we have threatening conditions or mild skies.

[weeniepatrol]

PV streamer / upper low are getting nuked by convection

[IcyTundra]

 https://twitter.com/JackSillin/status/1430516871950962689

[MississippiWx]

Already seeing the consolidation of a circulation around 13N 75W. This could help models latch onto a more consistent forecast. We will see.

[tropicwatch]

850mb vorticity is increasing near Colombia.
http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=vor&zoom=&time=

[MississippiWx]

850mb vorticity is increasing near Colombia.
http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=vor&zoom=&time=

Yep. Right at the coordinates I stated above your post.

[Blinhart]

This is forecast to entrain a massive amount of high TPW air from the EPAC.
Not only coming across Panama but Nic and CR as well.
This is very rare.
If it doesn't cross the Yucatan and rain some of this out, it will be packing a massive punch.

[url]https://i.postimg.cc/DZ2b0JC9/99L1.png [/url]

[url]https://i.postimg.cc/W40HjKK9/99L2.png [/url]

So I'm guessing this is why one post in the model thread shows Lafayette area getting almost 2 feet of rain.

[Blinhart]

Floater is on it.

https://weather.cod.edu/satrad/?parms=m ... =undefined

Looks like a very healthy wave right now, luckily from what I could tell no CoC yet.

[Blinhart]

Morning update from Jeff Lindner:

Potential hurricane threat for the western and northwestern Gulf of Mexico early next week.

Tropical wave is moving westward over the extreme southern Caribbean Sea along the northern coast of South America this morning. There is scattered convection in association with the wave axis, but no low level center. Global model guidance continues to indicate that surface low pressure will develop over some portion of the western Caribbean Sea either Friday or Saturday and move WNW or NW into the south-central Gulf of Mexico over the weekend.

There has been a significant shift in the deterministic model guidance over the last 24 hours to the right (east) with the majority of the guidance showing 99L heading in the direction of the NW Gulf of Mexico. While there has been some significant shifts in the deterministic runs of the models, the ensemble members continue to show a wide range of potential solutions from northern MX to the MS coast. Generally, the ensemble mean or average is to the left of the deterministic guidance runs. This creates a fair amount of uncertainty in the forecast, especially since there is such spread in the ensemble guidance. A lot of the guidance spread is resulting from the lack of a define surface center currently, and it will be critically important late this week on where the actual surface center develops.

Conditions over the Gulf of Mexico appear to be favorable for intensification and nearly all of the global guidance makes 99L a hurricane and some an intense hurricane over the NW Gulf of Mexico early next week.

It is too early to start discussing impacts since there remains a fair amount of uncertainty on the track. For now will continue to bump up seas by this weekend across our coastal waters…likely into the 10-15 foot range by Sunday into Monday and increasing tides. Rain chances will increase starting today and remain high into the weekend. Obviously, the forecast and potential impacts will have significant changes as the track become more clear in the coming days.

Residents and interest along the TX and LA coast should review hurricane plans and make sure hurricane supplies are fully stocked. Monitor forecasts closely and frequently.

Yeah I think all offshore rigs should be starting to Evacuate today, that way they are completely evacuated by Saturday.

[GCANE]

Floater is on it.

https://weather.cod.edu/satrad/?parms=m ... =undefined

Looks like a very healthy wave right now, luckily from what I could tell no CoC yet.

On VIS I am seeing some to the east moving clouds, not sure at what level they are.
One tower is firing near this with a little bit of helicity.

[Blinhart]

Floater is on it.

https://weather.cod.edu/satrad/?parms=m ... =undefined

Looks like a very healthy wave right now, luckily from what I could tell no CoC yet.

On VIS I am seeing some to the east moving clouds, not sure at what level they are.
One tower is firing near this with a little bit of helicity.

Yeah looking at Vis, I see the MLC trying to form, but don't think it is consolidated yet. But this system is forming a little to fast for my liking.

[GCANE]

Multi IR-Sat LL wind analysis

pictures hoster

[SoupBone]

Multi IR-Sat LL wind analysis

[url]https://i.postimg.cc/KYKbw6ph/2021al99-mpsatwnd-202108251200-swhr.gif [/url]pictures hoster

With those wind directions, what would this be classified as? A center?

[kevin]

Multi IR-Sat LL wind analysis

[url]https://i.postimg.cc/KYKbw6ph/2021al99-mpsatwnd-202108251200-swhr.gif [/url]pictures hoster

If I interpret this correctly the 1005mb/32kt value seems to indicate that at least in terms of wind this is already pretty close to TS strength. Of course it still needs some more circulation/CoC, but this invest is looking a lot better at this point than I expected.

[cycloneye]

 https://twitter.com/BenNollWeather/status/1430522854563590148

[Shell Mound]

Morning update from Jeff Lindner:

Potential hurricane threat for the western and northwestern Gulf of Mexico early next week.

Tropical wave is moving westward over the extreme southern Caribbean Sea along the northern coast of South America this morning. There is scattered convection in association with the wave axis, but no low level center. Global model guidance continues to indicate that surface low pressure will develop over some portion of the western Caribbean Sea either Friday or Saturday and move WNW or NW into the south-central Gulf of Mexico over the weekend.

There has been a significant shift in the deterministic model guidance over the last 24 hours to the right (east) with the majority of the guidance showing 99L heading in the direction of the NW Gulf of Mexico. While there has been some significant shifts in the deterministic runs of the models, the ensemble members continue to show a wide range of potential solutions from northern MX to the MS coast. Generally, the ensemble mean or average is to the left of the deterministic guidance runs. This creates a fair amount of uncertainty in the forecast, especially since there is such spread in the ensemble guidance. A lot of the guidance spread is resulting from the lack of a define surface center currently, and it will be critically important late this week on where the actual surface center develops.

Conditions over the Gulf of Mexico appear to be favorable for intensification and nearly all of the global guidance makes 99L a hurricane and some an intense hurricane over the NW Gulf of Mexico early next week.

It is too early to start discussing impacts since there remains a fair amount of uncertainty on the track. For now will continue to bump up seas by this weekend across our coastal waters…likely into the 10-15 foot range by Sunday into Monday and increasing tides. Rain chances will increase starting today and remain high into the weekend. Obviously, the forecast and potential impacts will have significant changes as the track become more clear in the coming days.

Residents and interest along the TX and LA coast should review hurricane plans and make sure hurricane supplies are fully stocked. Monitor forecasts closely and frequently.

Yeah I think all offshore rigs should be starting to Evacuate today, that way they are completely evacuated by Saturday.

Regardless of its eventual path, 99L seems likely to become a large and potentially very powerful hurricane. As of 06Z even the ever-bearish EPS has just trended toward the bullish GEFS, with numerous members showing sub-975-mb pressures, at least one of which is as low as the mid 940s. So there is now a very strong signal for a potent hurricane over the western Gulf of Mexico. Other models also concur with the EPS/GEFS in showing a (strong?) hurricane.

[kevin]

The Caribbean MPI is actually a bit lower than last week when it was theoretically able to support anything all the way up to a cat 5 (perhaps due to Grace?), but it's still more than sufficient to power a strengthening TS. And when 99L gets into the Gulf it'll be met by pretty much pitch perfect MPIs for explosive strengthening. Especially near Texas and Louisiana there is a large region that maxes out on the scale (so sub 880mb). This seems to indicate that this could very well be a storm that continues strengthening all the way up to landfall.

[GCANE]

Multi IR-Sat LL wind analysis

[url]https://i.postimg.cc/KYKbw6ph/2021al99-mpsatwnd-202108251200-swhr.gif [/url]pictures hoster

With those wind directions, what would this be classified as? A center?

A LL center, not a surface low.

[cycloneye]

 https://twitter.com/DCAreaWx/status/1430538409819447299