It's Florida. You'll need sunblock.
I'm not sure if your question means that you haven't traveled to Florida before, so pardon me if my explanation seems "flip."
1. It can be very hot in late October. When we were there last year at Halloween time, it was sunny and in the high 80's-low 90's every day.
2. The sun is hotter/different the further south you go. You should always use sunblock anyway, but I would especially think you would want to use it in Florida.