April is the flattest useful month in Senegal, and it is flat for a structural reason rather than a bad one. The North Atlantic has stopped sending winter swell to the north shore, and the southern hemisphere has not yet started sending it to the south. The peninsula is between jobs.
What that leaves is small, and the small is warming: the sea turns the corner from its March floor and begins the climb that ends in September.
If your dates are fixed to April, plan the week around Yoff and the beaches rather than the reefs, and treat any reef day as a bonus.

