Wave WSW of CV Islands

[Frank2]

As we know the Sahara is expanding every year, and how that'll affect the overall climate and cyclone development is mostly unknown:

http://en.wikipedia.org/wiki/Desertification

[Frank2]

As we all know the Sahara is expanding every year, and how that'll affect the overall climate and cyclone development (SAL, etc.) is unknown, though by my own observation over the many years it seems that SAL is more common now than in decades past...

Frank

[ConvergenceZone]

Well with conditions improving, we she should get MANY storms starting the 2nd week of August then as many here are predicting......If this is the case, then the year may still be really active...

[Ivanhater]

Wednesday morning model rundown. I will do another one after all the 12z runs come in.

Euro



Canadian



GFS OP(RIP)



Nogaps

[Riptide]

Thank you Ivanhater. Gives us a really good idea of where we stand as of right now.

[SoupBone]

As we all know the Sahara is expanding every year, and how that'll affect the overall climate and cyclone development (SAL, etc.) is unknown, though by my own observation over the many years it seems that SAL is more common now than in decades past...

Frank

Frank can you go into more detail about your line of thinking on this? The SAL has always fascinated me as well as its effects on storm development. I don't see a whole lot of people talking about it though so either they don't seem to be concerned or maybe they aren't paying attention to it. Thanks!

[MWatkins]

As we all know the Sahara is expanding every year, and how that'll affect the overall climate and cyclone development (SAL, etc.) is unknown, though by my own observation over the many years it seems that SAL is more common now than in decades past...

Frank

I would say that's probably an observation bias. Satellite resolution has been increasing since first visibles were introduced in the 60's, and the ability to see down through the atmosphere and detect water vapor hasn't been around that long.

So, we're seeing more than we've ever seen...it doesn't mean it wasn't there all along...it's just we didn't observe it.

And a note on the SAL...in my opinion we're measuring the tail instead of the dog when we discuss the SAL as a distinct entity. Instead, we should be talking about the conditions that cause a SAL to occur...high pressures, low atmosphereic vapor content and strong easterly trade winds. Put a big strong Azores high on the map and look south of it...and you will likely find a SAL.

In any case, I think our long-track portion of the season is getting close to beginning. The next 8 weeks are going to be very interesting indeed...glad I have saved up so much vacation time...I think I am going to need it.

MW

[Weatherfreak000]

Unreal. This feature should be fully emerging soon. Wind Shear is in the 10-20KT range and decreasing and the SAL is finally favorable. Convection ahead and behind it.


It's very easy to see why the models like this wave so much.

[KWT]

I think some people are way too reliant with the MJO at times, its a very useful helper but we were in a negative phase and got Bonnie...so its clearly not the be all and end all, just like every factor its a tool. In moderate La nina's its never going to get strong enough to dominate a season.

That being said I'd be surprised if we get true CV development, we could well see it developing further west. I personally like the ECM path and therefore development may once again be possible in the Western part of the basin with the wave just emerging from Africa.

Hard to ignore the models at least suggesting a fairly strong wave feature with this....the models were similar with Bonnie in terms of strength bar the ECM.

ps, that being said I do think the main season ramps up past the 10th, but we could easily see another system before then, before the season gets really going.

[Weatherfreak000]

I agree.


In that regard perhaps we are similar to 2005. The waves aren't doing so well right off Africa (although that may change very soon), and have had to form alot further west. This was happening in 2005 as well and we were drawing up comparisons between the genesis of Katrina and Bonnie near Florida. Point is if the waves don't develop as CV storms but develop further west it's always bad for us here in the GOM.

That makes me very nervous.

[KWT]

Indeed and we have quite a strong Azores high which will cause most systems to either stay between 10-13N or dive WSW out to 40-50W...after that really its just luck...

However in this solution I'd expect the ECM to be a decent guide.

The 12z GFS new op run doesn't really do anything with it.

[StormClouds63]

Ivanhater:

Based on the long-range forecasts you've been watching, what is your best guess for the date on which Colin will form?

[RL3AO]

Shear - manageable
SAL - OK
SST - Very good
Convergence - yes
Divergence - yes

I suspect a long track invest that we follow for days that has s2k saying "td by morning" then "its dead" 12 hours latter multiple times over a period of 3 to 5 days before developing or dying.

[Macrocane]

Yeah I agree with you RL3AO, it will be one of those disturbances that people think it's just below TD status at one time then it will weaken and then again strengthen and that will be the story for a few days before we finally see persistent convection and the real development will begin.

[Riptide]

The bigger concern is probably the massive Azores high on steroids that might push this beautiful, organized wave into the ITCZ. Ah, this season has had so many surprises...

[KWT]

The GFS new op run really does power up that Azores high but really doesn't do anything at all with this wave. Now its the op run we can see really how well it performs...

[Vortmax1]

I think some people are way too reliant with the MJO at times, its a very useful helper but we were in a negative phase and got Bonnie...so its clearly not the be all and end all, just like every factor its a tool. In moderate La nina's its never going to get strong enough to dominate a season.

And I agree KWT. Thank you.
The MJO is another tool/indicator. With the La Nina being moderate I have to keep reminding myself that the MJO is not really the deciding factor regarding possible development.
In other situations/phases the MJO is more relevant.

[Weatherfreak000]

Unreal. It's blossoming convection off Africa! 12Z Imagery showed the convection dieing and the 15Z reforms it. I think this wave may have a very potent circulation that may just be about done coming off the coast.

[Riptide]

Unreal. It's blossoming convection off Africa! 12Z Imagery showed the convection dieing and the 15Z reforms it. I think this wave may have a very potent circulation that may just be about done coming off the coast.

The tropical wave needs to gain some latitude, even 2-4 degrees would help.

[Weatherfreak000]

Not gonna happen when you have a 2005 like Azores High lingering about...