I'm not a meteorologist but I'm a weather enthusiast and it drives me nuts how much "90% chance of rain" or "scattered thunderstorms is misunderstood:
% chance precipitation = odds that it will rain at some point throughout the day. If there is a 90% chance of precipitation, there is a 90% chance that it will rain at some point during the day. This could be for an hour at 1pm or an all day affair. In Florida, the chance of rain is almost always over 50% every single day. Generally this means a passing shower or thunderstorm (which is honestly a good thing most of the time as it clears out the parks).
isolated thunderstorms = 15% or less of the area can expect a passing shower or thunderstorm. odds are low for multiple instances of precipitation.
scattered thunderstorms = 25-54% of the area can expect to see a passing shower or thunderstorm. odds are higher for multiple instances of precipitation.
showers = mostly an on and off affair of rain and clouds throughout the day.
Finally, Florida weather can change at a moments notice. In general precipitation forecasts are largely unreliable more than 72 hours out; especially in Florida. Don't plan around 10 day forecasts. Your best bet is to plan for 2-3 days ahead only and follow hourly forecasts. Mobile apps like RadarScope are very helpful as well.