Area of disturbed weather in NW Gulf of Mexico (Is Invest 90L)

[Steve]

I think it’s a middle level feature. I’ve been in New Orleans this week and they’ve had an incredibly hot August with most days into the mid to upper 90’s with lots of heat advisories and warnings. Today we’ve had a lot of wrap around thunderstorms - probably 5 so far - throughout the day. I’ll take it. Again ICON progged it last weekend but it hasn’t developed and it’s since backed off. If nothing else besides taking the heat away for a while it should do some work on the northwestern gulf water too. We all know that it doesn’t take named storms to do the work of balancing the heat

[cycloneye]

No mention of this area on the 8 PM TWO.

[Nimbus]

No mention of this area on the 8 PM TWO.

Surface pressures are falling tonight right along the Texas coast, several buoy readings down to 29.83.
Maybe NHC thinks this will move west inland and dissipate in the desert?

[tropicwatch]

Vorticity will need to pick up closer to the surface before the NHC gives a lemon. imo

[Steve]

Vorticity will need to pick up closer to the surface before the NHC gives a lemon. imo

I agree. I haven’t felt like looking at the mid and upper charts yet, so I’m going off the assumption this is a mid level feature where the one that went into Texas a few days ago was upper level energy. I don’t think it follows the track of the backing west upper low. Either the energy remains mostly disorganized at the surface (at least a few days) and stays in the Gulf or moves north into eastern Texas remains to be seen.

[Stratton23]

the mesocales seem to think that the vorticity will stall out and not move in land, thats why more of them are developing a weak but closed circulation because the energy remains over water longer
18z ICON brings back a weak closed low

[Teban54]

Vorticity will need to pick up closer to the surface before the NHC gives a lemon. imo

Actually, there's now significant vorticity building up at 850 mb in the past 3-4 hours, and the difference between 21z and 0z is night and day. The vort signature isn't as strong at 925 mb, though, so we'll see if there's more convection to bring it down. Right now the disturbance is pretty anemic in convection, but it was just past DMIN.

[tropicwatch]

Very nice, I posted before the 7pm vorticity was available. Might get a lemon at the next TWO but I hope to be asleep by then. The convection has waned quite a bit. So maybe no lemon

[Stratton23]

personally based on the mesocale guidance, and a slight uptick in the 18z GEFS, I would give this a 0/10% in my opinion, its at least worth watching, i remember global models werent really enthused about imelda forming from an area of low pressure similarly like this one

[Stratton23]

00z ICON has a TS that slowly rides offshore of the texas coast towards far SW lousiana, producing some insane rains over the gulf

[Category5Kaiju]

Not sure if it's this particular system per se, but the ICON seems very adamant about this becoming a TC. Doesn't have much model support otherwise though, which is interesting.

[HurricaneBrain]

The potential is there for a TD to develop from this. Very odd to see the NHC not give this a chance whatsoever. I’d go on a limb and say this has a 40% chance of developing. Just my opinion.

[tropicwatch]

The potential is there for a TD to develop from this. Very odd to see the NHC not give this a chance whatsoever. I’d go on a limb and say this has a 40% chance of developing. Just my opinion.

Well there is very little convection over the gulf and all the moisture is moving inland.

[TomballEd]

It doesn't need a lemon. It has finally started drilling down to the surface, but it is partially onshore in Texas already looking at CIMMS vorticity. Only the ICON tries to develop it. Ensemble support for a TD or weak TS looks fairly weak.

Still worth watching, if it can drift 100 miles S/SE and get entirely over water, it'd have warm water, decent shear, and it is finally drilling down to the surface. If models change tune and move it offshore, or NHC sees it drifting back offshore, it could get a lemon. Maybe even an orange. But it seems unlikely. But we watch.

The 50% 40% AOI is the best chance for a TC in the Gulf. Not a certainty, the early developers on the ensembles curve N through the Greater Antilles, but some do get into the Gulf.

[Steve]

https://www.tropicaltidbits.com/sat/sat ... t=vis_swir

Bubbling. New Orleans is under an outflow band at the moment and have a flood advisory out until 11:30am (at 8:30am Doppler indicated heavy rain. Minor flooding is expected to begin shortly. Rainfall amounts of 1-3" expected over the area.) I assume this will become a flash flood warning if the band stays parked. It's been gradually moving NE but hopefully there will be a break between bands.

https://radar.weather.gov/station/KHDC/standard

Edit - as expected, it's now a flash flood warning across metro New Orleans going out until 12:15pm. "At 9:12am radar indicated thunderstorms producing heavy rain. Between 1 - 1.5" have fallen. The expected rainfall rate is 1-4" in 1 hour. Additional rainfall of 1-3" is possible."

[Stratton23]

TomballEd almost all of the mesocale models keep this over water and develop a weak closed low, it has more support than you think lol

[Steve]

TomballEd almost all of the mesocale models keep this over water and develop a weak closed low, it has more support than you think lol

They do. ICON develops it, drops it south a little then comes back in around Morgan City, LA before riding the coast toward the Panhandle. Pressure doesn't ever depict to being all that low at the surface (like 1009mb) though it might be too small of a feature. It's what's coming out of the Caribbean (assuming Central Atlantic Wave discussion) that looks like the big dog in this setup. Here's the 7 day QPF Total. Much of that is likely to be underdone since New Orleans is shown to have 3-4" of rain, and it's already gotten about 2" so far today.



Also LOL at NAM 3km going for the 1001mb

[Steve]

From the NBDC:

Station 42035 (29.235N 94.41W - 22 nautical miles east of Galveston) NNE Winds at 3.9 gusting to 5.8 with pressure 29.96 and water temp of 86.2

Station KGVW (FAA) at 29.13N 94.55W has East winds at 11.1k

Most of the other reporting stations of the TX Coast are running 29.96/29.97 where FWL1/Freshwater Canal Locks off the LA Coast shows 30.15. Though 29.96 isn't low at all, it's low compared to a station not all that far away to its east.

[cycloneye]

Northwestern Gulf of Mexico:
A surface trough of low pressure over the northwestern Gulf of
Mexico is producing a large area of disorganized showers and
thunderstorms along and just offshore the coasts of Texas and
Louisiana. This system is expected to meander near the coast
through much of next week, and some slow development is possible if
it remains offshore. Regardless of development, heavy rains could
cause some flash flooding across portions of coastal Louisiana and
the upper Texas coast during the next few days.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...20 percent.

[Teban54]

Northwestern Gulf of Mexico:
A surface trough of low pressure over the northwestern Gulf of
Mexico is producing a large area of disorganized showers and
thunderstorms along and just offshore the coasts of Texas and
Louisiana. This system is expected to meander near the coast
through much of next week, and some slow development is possible if
it remains offshore. Regardless of development, heavy rains could
cause some flash flooding across portions of coastal Louisiana and
the upper Texas coast during the next few days.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...20 percent.

https://i.imgur.com/kl5ngnx.png

The recent blowup in convection likely contributed to the newly highlighted lemon: