Quiet tropics

Except for Irene, which has a nice satellite presentation with a clearly visible eye, the tropics are quiet today. Irene continues to steam out to sea, and is only a threat to shipping.

TD 10
The remains of TD 10 are near 15N 55W at noon EDT today, moving WNW at about 10 mph. One can see a clearly defined spin on satellite images, but there is no deep convection associated with the system. It is moving through the base of a huge trough that extends several thousand miles northeast to southwest across the central Atlantic, almost to the coast of South America. This trough is creating lots of wind shear over the remains of TD 10, keeping any re-development from happening. The GFS model indicates that the remains of TD 10 will take at least two days to traverse the trough and arrive in an area of lighter wind shear, which may happen by Wednesday night or Thursday as the system approaches Puerto Rico. By that time, it is questionable if there will be anything left of TD 10 to re-develop.

African Dust
The large cloud of African dust that moved off the coast yesterday is now nearly 1/3 of the way across the Atlantic. There is a fair bit of activity in the ITCZ south of this dust cloud, but anything that forms in the mid-Atlantic from the ITCZ this week will have a tough time overcoming the dry air associated with this dust cloud.

Caribbean
Strong upper-level westerly winds cover the Caribbean, and tropical development is unlikely here until these westerly winds subside. The GFS model is forecasting these winds to subside by mid-week, but the upper level winds across the Caribbean will still not look as favorable as they did in July when Dennis and Emily formed.

Jeff Masters