SSTs are really only small fraction of the formula in "cooking" up tropical and subtropical cyclones. Most of the action is really centered above water (as are the storms).

In specific relation to Invest 93L, this feature is not yet even a tropical cyclone, to begin with. It is currently a healthy tropical wave that has crossed the ocean from Africa, and has found itself in a much sweeter spot in the atmosphere than it has been in up until this time. SSTs are also typically far more supportive in this region (the Caribbean and GOM) during this time of year than the rest of the north Atlantic. There is nothing climatologically unusual about this. It is what we would expect for June.

Hope that helps.