Invest 99L in Central Atlantic

[Normandy]

Yes, nice big blowup over the low.

[TheRingo]

It certainly has grown some now going into the night hours. Very minimal shear ahead of it.

[Weatherfreak14]

Oh wow just got back from flordia and this looks pretty organized and getting better, it certanly has a shot.

[philnyc]

The LSU ESL graphics continue to show a great deal of very dry air across the Atlantic Basin. As long as this air is in place, I doubt that there will be any tropical system genesis occurring.

Could you post those graphics? I see the air as quite moist at mid-levels along the trade winds area (see CIMSS mid-level m0isture), and mid-levels is by far the most important for cyclone development.

[Stratosphere747]

The LSU ESL graphics continue to show a great deal of very dry air across the Atlantic Basin. As long as this air is in place, I doubt that there will be any tropical system genesis occurring.

Could you post those graphics? I see the air as quite moist at mid-levels along the trade winds area (see CIMSS mid-level m0isture), and mid-levels is by far the most important for cyclone development.

http://www.esl.lsu.edu/quicklinks/hurricanes/

[Blown Away]

Are we talking about 9 and 44???
http://www.tropmet.com/satellite/java/catl_ir_loop.htm

Looks like the blow up is near 9/44. Is there a LLC underneath the ball of convection?

[Dynamic]

IMO any development of this wave should occurs in or after reach the 50W where the ocean temp is equal or greater than 27 Celsius.

http://www.aoml.noaa.gov/phod/dataphod1/work/HHP/NEW/2007209atsst.png

[Normandy]

^The low is actually over 30C waters....remember its lat is very low (9-10 N).

[Matt-hurricanewatcher]

This looks like the most promising area in all of the Atlatnic. The low or northern part of a sharp wave which is from southwest to northeast,,,mostly centered near 44 at 9 north to 45.5 at 8 north. I would watch the area at 9.5/44.5 as convection fires over it, also being the northern side of this sharp wave, it has the best chance of developing a LLC. I will give this a 30 percent chance of becoming are third depression.

[canegrl04]

I will be excited if this wave formed into just a TD at this point.Comeon,baby

[NONAME]

Yes this does look good but as alway it need to detach itself from the ITZC.

[DESTRUCTION5]

Could this be what the GFS has crossing FL in 212 hrs?

[Cyclone1]

I gotta say, it looks great! http://www.ssd.noaa.gov/goes/east/catl/loop-ir2.html

[Weatherfreak14]

yes, i wonder how much more convection is going to blow on this tonight. and you can see a little spin to it also. Very exciting.

[philnyc]

The LSU ESL graphics continue to show a great deal of very dry air across the Atlantic Basin. As long as this air is in place, I doubt that there will be any tropical system genesis occurring.

Could you post those graphics? I see the air as quite moist at mid-levels along the trade winds area (see CIMSS mid-level m0isture), and mid-levels is by far the most important for cyclone development.

http://www.esl.lsu.edu/quicklinks/hurricanes/

OK, I see where you're getting it from. I would just say that you need to be very careful with mid to UPPER level water vapor because water vapor is obviously much lower at most of the top of the troposphere than it is at the mid levels, even in a hurricane. We really only care about middle levels (and obviously lower levels over the warm part of the Atlantic). So upper level water vapor images are no good because they often mask mid and low level vapor, and in combination charts like the LSU one:


the upper level vapor often masks the middle levels.

Look at the 07-29 18Z RH at 700mb and 300mb from the last GFS Global run:
First, here's the 300mb RH (upper level proxy):


Notice it matches the LSU charts pretty well - that is really dry air over a lot of the MDR (20% RH)!

Now here's the 700mb (middle level proxy):


Here we see the air is quite moist, over 50%, in a lot of the areas that showed 20% RH on the LSU map. So I personally think the LSU loop is a little misleading.

I think the CIMSS mid-level water vapor is better. And I'm sure the reason they finally added it to their products this season was to make it easier for us to find out what's going on with middle level vapor only. I just wish they'd put a key on it so we could know just how much RH is actually there. I hate having to go to the ARL all of the time to get a clear reading of the ML WV situation on any given day.

[Weatherfreak14]

Yes this does look good but as alway it need to detach itself from the ITZC.

I think, Im not sure, but I think it is trying to detach itself from the ITZC right now.

[windstorm99]

Wave looks desent but its moving into subsidence from the MJO which might make keep it from getting better organized.Shear is not to bad around 15-20kts in the area.

[philnyc]

Wave looks desent but its moving into subsidence from the MJO which might make keep it from getting better organized.Shear is not to bad around 15-20kts in the area.

Don't worry too much about the MJO. The pros are still not sure exactly how much effect it has. Obviously it should always be considered, but when the majority of other factors are favorable, its influence can be negligible.

[windstorm99]

Wave looks desent but its moving into subsidence from the MJO which might make keep it from getting better organized.Shear is not to bad around 15-20kts in the area.

Don't worry too much about the MJO. The pros are still not sure exactly how much effect it has. Obviously it should always be considered, but when the majority of other factors are favorable, its influence can be negligible.

Its also got some significant amount of dry air to its north.

[Blown Away]

Would you people stop teasing me! I'm about to have a lack of tropical weather meltdown.