Wave SW of Cape Verde Islands=(Is Invest 90L)

[BigA]

Area of convection south of Cape Verde Islands is associated with a wave that moved off Africa yesterday. Interestingly, it seems that this wave has gained convection, rather than losing it, since it left Africa.

Hard to tell if any spin whatsoever is associated with it.

[Gustywind]

Any pics loops graphics please?on this ???

[cycloneye]

5 PM EDT Pic:

[cycloneye]

8:15 PM EDT Pic: Some banding there?

[CYCLONE MIKE]

sure looks like it, have not heard anything mentioned about it throughout the day though. Just add it to the list of things to be watched.

[littlevince]

Hourly loop 12z to 00z


(source)

[MiamiensisWx]

It's interesting that no one has drawn suitable (and warranted) attention to this one. There is a possible weak surface low SW of the Cape Verde islands in the general vicinity of ~10-13 N and ~25 W. It's situated immediately east of the tropical wave axis further west, and low level convergence/good diffluence has aided persistent convection over the past ~24 hours. Some of the weak UL divergence and diffluence is enhanced by the close proximity of 99L and the wave axis further west and northwest, benefiting this system. There have even been signs of curvature/banding, and a mid level circulation has been evident as well. As 99L's surface low weakens because of strong upper level shear from an upper low at H2-H3 further north, this system will become increasingly noteworthy, especially since it is much further south and east. Shear will be marginal over this system as well, and SAL is very minimal/negligible in the vicinity.

18Z surface analysis from TAFB suggests that this "unknown" surface low is situated along the northward perturbance of the ITCZ (enhanced LL convergence) immediately E of the tropical wave axis.

http://www.opc.ncep.noaa.gov/UA/Atl_Tropics.gif

QuikSCAT indicates westerly winds in vicinity:

http://manati.orbit.nesdis.noaa.gov/dataim...oms/WMBds32.png

EUMETSAT data:

http://oiswww.eumetsat.org/SDDI/cgi/listIm...,d=1,v=400,pp=0

Convection has been increasing during the diurnal maximum.

[blp]

Interesting.... Not much model support right now. The 18Z GFS initializes the 850 vort but disipates it as it heads SW. Let's see if it holds together as SAL and SST's should not be a problem.

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... =Animation

[gatorcane]

Well this is an interesting area I have to say. All the key factors for development seem to point at a go at this point unlike most of the Atlantic basin which is dominated by king TUTT at this point

Even the wind shear is decreasing out ahead of this area. I do think this is an area to watch over the next couple of days. Its only negative is close proximity to 99L which may hamper development. If 99L takes off, this area will not be able to develop

But positives include SAL is low, oceanic heat content is high, and convection is good.

The other issue is can it generate some cyclonic turning or will it just traverse the MDR as a strong, pulsating wave?

[alan1961]

Think this area has a far better chance of organizing than 99L does, a wide moisture field too feed on, no sal inhibiting it, shear looks no problem, probably just devoid of any LL spin at the moment although some banding is evident so it could be on its way but only time will tell as always.

[MiamiensisWx]

Gator, its proximity to 99L is only helping it. As I mentioned in the preceding post, the adjacent wave axis and associated northward "bend" in the ITCZ is increasing the low level convergence. At the same time, 99L is broadening the surrounding 850 mb wind fields, aiding diffluence. Divergence from 99L is also producing ascent. These factors are allowing persistent initiation/development of convection. A mid level circulation is actually present if you closely peruse satellite data. 850 mb LL vorticity is good as well, and shear/SAL is minimal as mentioned.

Forget 99L (ex-98L); I have never been particularly bullish on its (fishy) prospects. Watch THIS ONE...

For what it's worth, climatological support is decent for MDR development as we move into August (compared to July). Keep that fact in mind.

[gatorcane]

For what it's worth, climatological support is decent for MDR development as we move into August (compared to July). Keep that fact in mind.

No doubt I agree with that, an area around with this blob is located does warrant close attention because it is AUGUST not JULY anymore. In addition, its traversing a near perfect lattitude in the MDR for tropical cyclone formation. It's just far enough away from the ITCZ where it can become its own entity but south enough to enjoy SSTs in the 80-81F range while missing the SAL to the north around where 99L is having issues at the moment.

[cycloneye]

Pic at 11:00 PM EDT:

[cycloneye]

Pic at 10:45 PM EDT:

[HURAKAN]

Very interesting system.

[HurricaneHunter914]

99L has the LLC, but no convection. Future 90L has the convection, but no LLC. Maybe they should trade?

[Matt-hurricanewatcher]

This one has the highest chance of going all the way since Bertha. You have nice convection with a very sharp wave, possibly even the first signs of a LLC. If this thing can have favorable environment for the next 24-36 hours...I would give this a fair chance of developing into something.

[cheezyWXguy]

99L has the LLC, but no convection. Future 90L has the convection, but no LLC. Maybe they should trade?

True, there may not be a llc at this time, but there is some very obvious low to mid level turning in this storm, and it appears pretty well organized. If convection persists tomorrow, then I expect it will become 90L by tomorrow afternoon.

[KWT]

This will very likely be 90L unless we see it go poof in the next 6-12hrs, at Dmax there is some pretty decnt convection and the conditions for this system do look pretty good as of now as well. This could well eventually go on to do something we shall see.

[Nimbus]

Thanks to 99L there is a lot more moisture for this wave to work with. Also it is far enough south to take advantage of the higher SST's in a lower shear environment.