Central Atlantic Waves Discussion Thread

[rockyman]

The wave near 41N bears watching. If it travels 6 degrees longitude per day, it should reach the Windwards by Tuesday or Wednesday. Here's a brief summary of available info.

Conditions look pretty good for development (area is in light green):
http://rammb.cira.colostate.edu/project ... xyrfpr.gif

TWD mentions "low cloud swirl" near 10/41:
AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 41W SOUTH OF 20N MOVING
WEST 10 KT. A SMALL SWIRL OF LOW CLOUDS IS NEAR 10N 41W.
CONVECTION IS CONFINED TO THE ITCZ. WIDELY SCATTERED MODERATE
CONVECTION IS FROM 7N-10N BETWEEN 40W-45W.

Shear is low:
http://cimss.ssec.wisc.edu/tropic/real- ... g8shr.html

There are a couple of pockets of LL convergence:
http://cimss.ssec.wisc.edu/tropic/real- ... 8conv.html

As well as vorticity near the surface:
http://cimss.ssec.wisc.edu/tropic/real- ... 8vor4.html

Some convection has been firing throughout the day

Possibly far enough south to avoid SAL:
http://cimss.ssec.wisc.edu/tropic/real- ... split.html

Main negatives--still attached to ITCZ; no model support yet

Edit: Changed title to include wave near 30N

[caneman]

The wave near 41N bears watching. If it travels 6 degrees longitude per day, it should reach the Windwards by Tuesday or Wednesday. Here's a brief summary of available info.

Conditions look pretty good for development (area is in light green):
http://rammb.cira.colostate.edu/project ... xyrfpr.gif

TWD mentions "low cloud swirl" near 10/41:
AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 41W SOUTH OF 20N MOVING
WEST 10 KT. A SMALL SWIRL OF LOW CLOUDS IS NEAR 10N 41W.
CONVECTION IS CONFINED TO THE ITCZ. WIDELY SCATTERED MODERATE
CONVECTION IS FROM 7N-10N BETWEEN 40W-45W.

Shear is low:
http://cimss.ssec.wisc.edu/tropic/real- ... g8shr.html

There are a couple of pockets of LL convergence:
http://cimss.ssec.wisc.edu/tropic/real- ... 8conv.html

As well as vorticity near the surface:
http://cimss.ssec.wisc.edu/tropic/real- ... 8vor4.html

Some convection has been firing throughout the day

Possibly far enough south to avoid SAL:
http://cimss.ssec.wisc.edu/tropic/real- ... split.html

Main negatives--still attached to ITCZ; no model support yet

9 and 30 beginning to interest me too. needs to gain some Lat. Looks like players are coming on to the field. I think this upcoming week the light switch will be thrown. Looks like things are a changin in the basin.

[rockyman]

MM5 sort of develops 30

http://moe.met.fsu.edu/cyclonephase/mm5 ... 12/10.html

[caneman]

18Z GFS does as well

[rockyman]

Is this the storm at 144? If so, it's showing an early recurve?

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... hour=144hr

[Jam151]

Is this the storm at 144? If so, it's showing an early recurve?

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... hour=144hr

maybe. these guys seem to think it wuld turn back west first.

http://www.independentwx.com/discussion

[caneman]

Is this the storm at 144? If so, it's showing an early recurve?

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... hour=144hr

Watch how it backs back West at end of run though.

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

[MWatkins]

Don't look now but the new GFS run looks like it wants to develop the wave at 30W...the little one. That's the first time there's been any real hint this is on the way...through 54 hours:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... v_054m.gif

And the wave behind it...

MW

[wxmann_91]

Is this the storm at 144? If so, it's showing an early recurve?

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... hour=144hr

Even without looking at further times, the 1024 mb high, with height contours E-W, will support a turning to the west.

[rockyman]

Should this thread be merged with this one? I didn't mean to create a duplicate thread:

http://www.storm2k.org/phpbb2/viewtopic.php?t=88402

[southerngale]

No, rockyman. It's better not to have one giant thread about all Atlantic waves anyway. More precise, shorter threads are better anyway.

From the rules and guidelines thread at the top of the forum:

Storm2K has decided not to have an "official" thread for all Atlantic waves,GFS, etc... Although some may like it this way, many members don't want to read an entire thread about all waves and would prefer to see a thread title that captures their attention about a particular wave. Also, we'd really like to get away from everyone thinking they have to post in this "official" thread, etc. Everyone doesn't read every post in every thread, so let's not jump on people who happen to repeat something that someone else already said. Obvious duplicate threads may still be locked though and blantant repeated abuse of this will not be accepted.

[caneman]

Starting to see some nice consolidation here.Lots of red popping up in the convection. We haven't seen either to much this year. This may be ready for liftoff

[caneman]

It's Looking sweet....For those of you who don't know, just click on the suspect area t o zoom in

http://wwwghcc.msfc.nasa.gov/GOES/goeseastfullir.html

[TampaFl]

It appears the players are lining up on the field. And starting to look better this morning. The one near 35 west especially. Thoughts and comments welcomed.


Robert


http://oiswww.eumetsat.org/SDDI/cgi/listImages.pl?m=bnw,a=0,sa=8,pr=COLOUR,f=1,c=IR_108,se=0,n=6,d=1,v=400,pp=0,t=200608200900#controls

[Scorpion]

Convection is sustaining itself or increasing. Definite positive for development.

[caneman]

Yeah, this is a first this year. I believe someone may have flipped the switch

[cycloneye]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN AUG 20 2006

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN
SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE
AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION
IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...
AND METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0945 UTC.

TROPICAL WAVES...
TROPICAL WAVE OFF THE COAST OF W AFRICA IS ALONG 31W/32W S OF
19N WITH A 1012 MB LOW ALONG THE WAVE NEAR 9N MOVING W 15-20 KT.
LOW IS EMBEDDED WITHIN THE ITCZ AXIS WITH AN INVERTED-V
CURVATURE OBSERVED ON INFRARED SATELLITE IMAGERY. CONVECTION IS
WITHIN THE ITCZ AXIS.

[Hyperstorm]

The tropics are waking up!

Remember the MCS that was inland over Africa with good rotation at a very low latitude several days ago? Well, it is now located very roughly near 8N, 30W as a tropical wave/low. This system has persisted since it came off land, but has been in a status quo despite the seemingly favorable conditions. I think it might have been set back by the close interaction with the ITCZ. There is a trigger however that is sparking major convection today.

A squall line associated with the wave/low that is about to move off Africa raced ahead of the low and has met the system SW of the Cape Verde islands. This area of moisture has just sparked the fire as it is blocking any dry air intrusion the system. Convection is on the steady increase with cloud tops colder than -70*C. It seems that the system is gyring into a larger low pressure area pulling moisture from the ITCZ ahead of it. This process of development normally takes time (that's why it hasn't developed yet), but if conditions remain the same, I personally think we could see this become a classified cyclone as soon as Tuesday.

Behind this one there is another wave about to move off the continent. Yesterday, the system was located rather far north near 15N. The system has moved WSW and looks to have a good mid-level cyclonic turning near 12N-13N. The system is re-firing convection over water with the low still being inland. Impressive is that the system had to wait until moving over water to gather convection. Of course, it'll have to persist over water for any development to occur. If it holds on, this one could even develop before the other one as it already has a good cyclonic turning that could go down to the surface with any increase of convection over it.

I think we should start dusting off those tracking charts...

[SouthFloridawx]

Good post hyperstorm.