Good morning! Today is August 20, which marks the tradition rapid uptick in activity in the Atlantic basin. Seemingly right on cue, it appears we will soon have our first Cape Verde (east Atlantic/west coast of Africa) system of the season. This will emerge from the cluster of storms stretching over quite a bit of latitude in the eastern Atlantic; it appears one of the clusters of storms is becoming dominant which will allow it to develop further -- especially as it starts to move slightly farther north and breaks free of the Intertropical Convergence Zone (ITCZ).
Most of our forecast models develop this system into a tropical cyclone by the end of the weekend and move it on a west-northwest heading toward the central Atlantic by the middle of next week. The amount of latitude this system gains as it moves north will be critical in determining its ultimate fate. At this point, essentially every one of our forecast models recurves this system will east of the United States as multiple troughs of low pressure prevent the subtropical high from strengthening sufficiently to keep the system on a westerly track. I will caution, though, that these early model forecasts -- without a true center of circulation -- and many days away from these low pressure troughs emerging off the US east coast should be taken with a grain of salt. This should be our first long-tracked system of the year and is worth watching over the next several days, but at this point, no forecast models indicate a threat to the United States. As long as enough of the dry air out ahead of it erodes over the next few days, conditions should be optimal for strengthening and some of the first hurricane model guidance coming out this morning takes this to a strong hurricane 5 days from now in the central Atlantic.
Elsewhere, things are relatively quiet as the tropical wave we were looking at in the Caribbean pushes onshore in Central America. Low pressure aloft will develop in the Gulf of Mexico or off the east coast of Florida this weekend and early next week as an upper level front/surface trough moves into the southeast. Often, this time of year, these areas can spawn what we call "home brew" tropical systems -- systems that start as extratropical and become tropical. A similar situation occurred when Tropical Depression 5 developed. So, don't be surprised if something does spin up along this frontal system in the southeast or in the Gulf over the next 3 or 4 days, starting tomorrow.
Have a great weekend!
Brian
