Models show more active Atlantic

[LaBreeze]

Yep, I remember Lili well in 2002 - she took my entire garage and patio and part of my roof, not to mention a couple of large oaks. Still she was nicer to me than Rita.

[mobilebay]

And the 00z GFS...shows nothing!

What? It still develops a TC in the Atlantic.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_096m.gif

[Derek Ortt]

GFS is back in line with reality, developing now what looks like a TD or a TS, but turns it north just west of the CV islands.

Really don't see anything developing there for a while

[kenl01]

Even AccuWeather's perspective is not very impressive:

The last tropical wave in the Atlantic recently emerged from Africa Friday and is now along 22 west, south of 13 north, moving west at 15 knots. There are a few thunderstorms along this wave, and there even appears to be a broad circulation present. Although there is no shear and the waters there are warm enough for development to occur, there are some limiting factors. There is a substantial blast of Saharan dust coming off Africa just to the north of the wave, which will hinder further development. Also, there is a relatively hostile environment to the west of the wave, which would probably subdue anything that could develop in the near future.

[Hyperstorm]

It is quite normal for the first half of August to see many upper-level lows in the Western Atlantic. After all, the TUTT is a semi-permanent feature. However, what's happening this year is that there has been no major progression of the pattern. Usually, we see upper-level lows moving in a decided direction, only to be replaced by another one in a few days. But this year, the upper-lows have been stagnant. Thus, any tropical waves that try to move westward are shredded to pieces due to their persistance. I would be interested to find out from any research why that happens in some years (i.e. 2000), with the lack of a defined El Nino.

Regarding the tropical wave that just recently moved offshore...

It has remained persistent, but in a status quo. I have not seen any increase in organization since it moved off land, but the convection seems to have merged with the ITCZ with a broad cyclonic circulation. This is a very interesting situation with seemingly favorable conditions.

I think what'll happen is that the system will continue moving west and continue merging with moisture from the ITCZ that is just ahead of it. If conditions remain right, it should start gyring into a giant low pressure area over the next 48 hours. It's happened before and if it does, it could very well kick it into classifiable mode.

The next powerful wave about to move off Africa is too far north for my liking. We'll have to wait to see if it can move WSW like the last one did. I think the chances of it persisting near 15N are not very good with marginal SSTs and the heart of the SAL awaiting.

I think this upcoming wave will help the one that is south of the Cape Verde islands after 36 hours. It'll be interesting to watch that interaction.

[ThunderMate]

What are the models showing about our wave this morning? Are they still developing it and where is it heading?

[cycloneye]

What are the models showing about our wave this morning? Are they still developing it and where is it heading?

GFS dropped completly the fish hurricane type system in the 00z and 6z runs.In fact even those runs didn't have a low tracking thru the Atlantic from that system.

[Frank2]

Overall, conditions in the Tropical Atlantic seem to be as unfavorable for development as they could be, for this time of year - even Steve Lyons just gave it a passing mention this morning, saying only that "conditions are unfavorable in the Atlantic".

That's why I was upset yesterday - you can't rely on a 344-hour model output when it comes to making such a bold statement as one or two did here yesterday, since the model run is very likely to change a day or two later...

Frank

[cycloneye]

Overall, conditions in the Tropical Atlantic seem to be as unfavorable for development as they could be, for this time of year - even Steve Lyons just gave it a passing mention this morning, saying only that "conditions are unfavorable in the Atlantic".

That's why I was upset yesterday - you can't rely on a 344-hour model output when it comes to making such a bold statement as one or two did here yesterday, since the model run is very likely to change a day or two later...

Frank

One of the factors Frank is what I posted in another thread,The big Sal Outbreak.

[ThunderMate]

Well doesn't our wave still have a good chance of developement and doesn't the other one behind it also??

[MortisFL]

I think the wave in the Eastern Atlantic still has a moderate chance. It's underneath the SAL and has persisted with convection.

[SouthFloridawx]

I think the wave in the Eastern Atlantic still has a moderate chance. It's underneath the SAL and has persisted with convection.

Yep this wave has consistenly fired up with convection. It has not gone "poof" like the other waves have in the recent past.

It's not in a great area of SST"S but, it can gain some slow development as it moves westward.

[Frank2]

But, it appeared more isolated yesterday - it's since merged with the ITCZ...

[x-y-no]

Jeff Masters has a cute set of guidelines for judging the guidance the global models give WRT cyclogenesis in todays blog entry:

1) If two or more of the reliable models (GFS, NOGAPS, GFDL, UKMET) are forecasting develoment, watch out.

2) If none of the reliable models are forecasting development, watch out. The models miss most tropical storm development.

3) If just one of the reliable models is forecasting development, you can probably discount it.

There's definitely something to it.

[ThunderMate]

12z GFS started...out to 48 hours

[Tampa Bay Hurricane]

The Atlantic looks quite moist..once we lose some of the SAL
and shear...we'd better watch out...Jeff Masters has made some
valid points in his writings...it may be quiet at this time...but
I do not expect that quiet to last long unfortunately.
Things are going to get very favorable for storm
formation within about 7-10 days...I expect noticable
changes.

[ConvergenceZone]

The Atlantic looks quite moist..once we lose some of the SAL
and shear...we'd better watch out...Jeff Masters has made some
valid points in his writings...it may be quiet at this time...but
I do not expect that quiet to last long unfortunately.
Things are going to get very favorable for storm
formation within about 7-10 days...I expect noticable
changes.

That's the thing, as much as I want you to be right, there's been no evidence that this brutal shear will abate anytime soon. Usually you see some type of evidence before it starts to happen, and there just isn't any....People were saying the same thing about the shear going away in late July and it just continues to hang on.

[ThunderMate]

Did the GFS lose the system completly or is it still there on the 12z?

[Meso]

It's still there.. although doesn't do much with it at all...
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _204.shtml

[cycloneye]

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

Here is the full 384 12z GFS loop that goes to Labor Day.Labor Day weekend without anything to track? Well at the end of the loop it shows a significant system South of Cape Verde Islands.