***7/30/11: Please note, this post concerns Invest 91 from last year - 2010. If you're looking for this year's (2011) Invest 91, which is about to become "Emily", please go to this post instead.
------------------------------------Original post follows:
The above is a recent visible satellite image showing a couple of interesting features off the coast of Africa. First and foremost, in the red circled area, is "Tropical Invest 91". "Invest" is a term that the National Hurricane Center (NHC) uses to describe an area of interest (or investigation) that has not yet become a Tropical Depression, Storm or Hurricane.
The convection (thunderstorm activity) has become more dominant and well defined around what appears to be a developing circulation center associated with the system this afternoon. If Invest 91 isn't already a Tropical Depression, it will be very soon if this trend continues...
You can see more of the convective development I was talking about in the close-up visible image below:
Back to the first image at the top of the post, the white circled area notes more dust that is floating West off of Africa (note the milky-white coloration within the encircled area). So far, Invest 91 is developing South of the most widespread dust cloud, which will enhance development as it has full access to the beaming tropical sunlight.
The midday computer forecast models didn't stray too far from the early morning versions (except for a gradual northward turn toward the end of the forecast period) as far as the potential track of this system is concerned:
The brighter red track on the above map shows what the GFS Model thinks will happen to the system. It is obviously very early on in the developing stages of this system, but here is an even closer view of how the GFS model depicts this system, which would by then be Hurricane Colin, about 1 week from today (click image to enlarge):
As I said, it's very, very early in the game, but this gives you an idea of some of the tools that meteorologists have to work with. Lets see how the situation unfolds over the coming week. It will be interesting to look next Sunday at what the actual position of the storm is relative to the computer forecast model snapshot above.