You have what I think is early blight.Need more pics of stems to confirm. Once you get a blight there is no cure, as the old adage goes an once of prevention is worth a pound of cure. If there is only a few leaves you can try trimming them off and spraying with daconil thats listed for tomatoes. It may be too late though.

Maybe just crappy weather , but next year you may want to start a spray program or look at more disease resistant varieties. What variety is this?

Here is a link that might be useful: Early and light blight info

Welcome to Florida. It's even worse in Miami.