A very strong African Easterly Wave born in far eastern Africa back on August 14 exited the coast Sunday afternoon. It quickly acquired a mid-level circulation and later on Monday developed a low-level circulation as well, prompting the upgrade to TD4. As of this writing, it has deep convection in large spiral bands, but not too concentrated yet over the center... divergence aloft is healthy, with a stronger outflow channel to its south.
The 21Z advisory places the center at 12.3N 21.0W, or just south of the Cape Verde Islands. The satellite-estimated intensity is 30kts and 1007mb. Motion is toward the WNW at 11kts.
It is forecast to slowly intensify and track NW through a weakness in the subtropical ridge. It seems unlikely as of now that this will be the type to travel the full distance across the basin before recurving. The next name on deck is Debby.
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