ATL: INVEST 90L - Discussion

[Stormcenter]

Station 42019 pressure down 29.79 in as the lowest I could find in the area

New tower exploding around center.

[Frank P]

Station 42019 pressure down 29.79 in as the lowest I could find in the area

New tower exploding around center.

Is this where you are seeing the HT?

[Stratton23]

Once this low adds that energy from the caribbean wave, then it might be game on, this is going to have a lot of moisture to work with thats for sure

[Stormcenter]

Yes.


quote="Frank P"]

Station 42019 pressure down 29.79 in as the lowest I could find in the area

New tower exploding around center.

Is this where you are seeing the HT?
https://i.ibb.co/7YVMXNt/GOES16-1km-vis-202409052215-24-00-29-00-98-00-86-00-vis1-ltngge-hgwy-warn-weathernerds.png[/quote]

[Frank P]

Hurricane models just starting to run

[Stratton23]

So far with the hurricane models running, they do a similar south track like the ICON, but are much stronger as well, most in the 991-996 range

[TomballEd]

I wonder if NHC requests a recon tomorrow. The area of favorable shear over it is skinny, but there is plenty of upper divergence and lower convergence. Vorticity is stretched more (per CIMSS analysis) more than what an actual TD would have. There is, as noted above, new convection near the center. A good burst of convection might tighten it up enough to be a TD. Ensembles see it, but few have more than TD or minimal TS. But Humberto and all, you never really know.

Just had a nice rain band come through where I work just W of the big airport. This whole washed out trough semi-stalled over the NW Gulf has saved me on air conditioning bills.

ETA- South movement makes sense, the upper air flow that brings the first Autumn front to the Texas Gulf Coast (dewpoints in HOU getting down to 60F???) would push it S

Andy Hazelton who helped develop and still works on the HAFS said they are designed for existing TCs, and may not be accurate for invests.

[cycloneye]

Northwestern Gulf of Mexico (AL90):
A large area of disorganized showers and thunderstorms persists over
the northwestern Gulf of Mexico in association with a broad area of
low pressure that is interacting with a nearby weak front.
Upper-level winds are expected to remain unfavorable for significant
development of this system while it meanders over the northwestern
Gulf and eventually merges with an approaching frontal system by
late Friday or Saturday. Although tropical cyclone development is
unlikely, heavy rainfall is expected to continue across portions of
the northern Gulf Coast during the next day or so. Additional
information on this system can be found in products issued by your
local National Weather Service Forecast Office and High Seas
Forecasts issued by the National Weather Service.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...10 percent.

[Stratton23]

10% still? Based on the hurricane models, this should easily be at 40%-50%, NHC still being too conservative again

[tolakram]

10% still? Based on the hurricane models, this should easily be at 40%-50%, NHC still being too conservative again

I don't think so, we'll see.

[Frank P]

10% still? Based on the hurricane models, this should easily be at 40%-50%, NHC still being too conservative again

Unless I missed something the hurricane models didn’t look very bullish to me.

[EasyTiger]

It appears that after a long and arduous battle, this thing is going to retreat for a bit while it waits for incoming reinforcement

[Frank P]

It appears that after a long and arduous battle, this thing is going to retreat for a bit while it waits for incoming reinforcement

A few guys from reinforcement have appear overnight to help shore up the north and south side of the LLC for our little wannabe system. Appears to be continuing its S or even SSE trek in the GOM per the IR sat loops.

[GCANE]

Monday, a large part of the western GoM will be under a strong anticyclone.
Could see some good development then.

[ChrisH-UK]

90L is looking nice this morning the circulation is partially under the main convection and is moving under. shear wise it is a bit of a lower shear pocket at the moment.

[mpic]

I guess I'm going to have to break down and watch local weather because apparently one of the local Houston tv stations is alluding to another Harvey for us next week. I'm hoping that the message was more along the lines of "the season isn't over and be vigilant" and somebody ran with it. I hope the latter is the case and I understand how difficult it must be to keep the public aware without overplaying or underplaying when you just don't know.

[HurricaneBrain]

We have the majority of models showing development from this system. I would say development odds are much higher than 10% when this merges with the Yucatan system in a few days. Why the NHC is only showing 10% for Invest 90L and 20% for the other system is beyond me. My guess is they are waiting for the merge to actually come into fruition before they slap an orange or a cherry on a singular AOI.

[wxman57]

That trof digging into the NW Gulf this weekend with the cold front across the northern Gulf will produce a lot of wind shear across the NW Gulf this weekend into early next week. Lots of dry air flowing off the Texas coast, too. Models that develop a stronger system may not be handling that well. I still think that real development chances over the next 7 days (by early next week) are closer to 70-80%, not 10% or 20%. The shear may be dropping off by Monday/Tuesday, but it won't be gone. Environment could support a sheared TS. Of course, if the shear should drop off for just a few hours, then we can never rule out a hurricane. It better not come to Houston. I still have about 100 ft of Comcast's cable down on my back fence. Been trying to get them out to fix it for 2 months.

[Sciencerocks]

This has a well defined LLC and is trying to form convection over it. I wouldn't be shocked to see it upgraded in the next 24 hours....

[wxman57]

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

This has a well defined LLC and is trying to form convection over it. I wouldn't be shocked to see it upgraded in the next 24 hours....

The first cold front of the season is nearing the Texas coast now. Shear over the low will be increasing tonight, along with plenty of dry air moving offshore. That will cause it to weaken. While I am surprised that the NHC has been downplaying it, we'll have to wait until early next week for the shear to abate and moisture to increase.