Another GOM Disturbance

[cycloneye]

A small, non-tropical area of low pressure has formed in the
central Gulf of Mexico about 250 miles south of Pensacola, Florida.
Significant development of this system is not expected due to
strong upper-level winds and proximity to dry air. The low is
forecast to move northeastward over the Big Bend area of Florida
late Wednesday or early Thursday.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

[northjaxpro]

It's kind of forming before our eyes, assuming that small tight spiral and new convection continues to grow. That's a very compact and circular spin.

I agree. I think it is developing slowly. As I mentioned earlier on this page, I was thinking that tomorrow would be the time this feature really begins to get going, especially with the old boundary forecast to lift north, but. Convection indeed seems to be gradually picking up this evening.

It will be an interesting next few days potentially.

[northjaxpro]

Well, as I was posting above, NHC gives a mention finally of our feature in the latest TWO.

[Tampa Bay Hurricane]

Looks like another round of heavy rain and potentially some windy weather headed for the eastern gulf.

[GCANE]

A 4000 CAPE Ridge is sitting over the center of the surface low.

[northjaxpro]

I would have put development percentages at 20% at 48 hours and 30% at 120 hours for right now.

If I were betting, I am just about certain those NHC percentages this time tomorrow are going to be higher than what they are now.

[BobHarlem]

Which area are people talking about here, the area due south of Pensacola/Mobile in the central gulf or the area closer to Florida (Which you can barely see on the long range tampa radar)?

[Emmett_Brown]

A 4000 CAPE Ridge is sitting over the center of the surface low.

Interesting. I'm not a pro met, so always eager to learn... I usually see CAPE discussed with severe thunderstorm formation, tornadoes etc., where the atmosphere is cold in the upper levels. How does CAPE related to warm core systems like developing TC's? I notice the NHC calls our little vortex a "non tropical low", so I am assuming it is not warm core at this time, perhaps due to the dying front?

[GCANE]

Cloud tops getting colder on the convection wrapping around the swirl.
Looks interesting.

[northjaxpro]

BobHarlem. it is the newly developed vortex area in the Central GOM due south of Mobile/Pensacola by about 250 miles or so.

[floridasun78]

no more rain for my area south fl today their was bad flood miami beach

[GCANE]

A 4000 CAPE Ridge is sitting over the center of the surface low.

Interesting. I'm not a pro met, so always eager to learn... I usually see CAPE discussed with severe thunderstorm formation, tornadoes etc., where the atmosphere is cold in the upper levels. How does CAPE related to warm core systems like developing TC's? I notice the NHC calls our little vortex a "non tropical low", so I am assuming it is not warm core at this time, perhaps due to the dying front?

For a develping TC, that needs convection to form a warm core, CAPE works the same way.
TC development occurs whem persistant thounderstorms fire around a CoC.
The higher the CAPE (Available Energy) the likelyhood the thunderstorms will be stronger.
Raising air parcels release heat when they phase change from vapor to ice at the mid layer of the air column, about 400mb.
The warm differential temperature can persist if the mid-layer is nearly saturated. Water vapor holds heat well as opposed to dry air.
A high rain-rate cell is usually a good indication that this process is underway.
Thunderstorms give off mid-level heat in all directions.
But, If a population of thunderstorms ciculate around a common center (CoC) they concentrate the heat at the CoC thus creating the persitant warm core.

[lrak]

Now I understand a bit more....thanks GCANE may have to change my disclaimer

[stormhunter7]

wonder when this meets classification for tag, or when will tropical model suite begin run?

[RL3AO]

wonder when this meets classification for tag, or when will tropical model suite begin run?

I don't know what guidance they can get internally with test invests, but it looks like they're tracking it and probably getting some model output.

GENESIS015, AL, L, , , , , 78, 2017, DB, O, 2017080200, 9999999999, , 015, , , , GENESIS, , AL782017
GENESIS016, AL, L, , , , , 79, 2017, DB, O, 2017080200, 9999999999, , 016, , , , GENESIS, , AL792017

[Hammy]

I'm thinking the chances might be low because of the size--the models aren't really able to pick it up at the moment. Hopefully it'll hold together enough to warrant getting a plane out tomorrow.

[ROCK]

Look on the 1km sat...surface low is about to take off. Percentages were low because of no model support. This is now cast!! Wooo!!

[gatorcane]

850mb vort is increasing. Think an invest tag would make sense:

[ROCK]

I will call it. Franklin tomorrow..IMO

Which is a TS name if I ever heard one..look out!! Here comes Franklin!! Yeah that's pretty weak..js..

[ronjon]

The mesoscale models seem to do a better job at genesis of these small features. The RGEM and NAM 3k did well with Emily. The link below is the latest RGEM run.

https://www.tropicaltidbits.com/analysis/models/?model=rgem&region=seus&pkg=mslp_pcpn_frzn&runtime=2017080118&fh=6