According to Florida statutes any person who has a vehicle in Florida for more than 90 days during a 365 day period (the days do not need to be consecutive) must purchase personal injury protection and property damage liability insurance coverage.

Personal injury protection (PIP) insurance will compensate a loss due to injury regardless of who is charged with causing the crash. PIP typically insures the policyholder and relatives that live in your home.

Property damage liability (PDL) pays for damage you cause (and are liable for) to other people's property in a crash involving a motor vehicle.

So if the car you are borrowing from your Uncle is in Florida 90 days or more this type of FL coverage will need to be put on it. You Uncle will need to check that his insurance will cover you until you are able to get the auto insurance required of a car in Florida.

Since you are not an owner of the car you will have to find an insurance company that will allow you to get insurance on a car that you do not have insurable interest on. We work with such a company so you can start here to try to get a Florida car insurance quote.

As for what could happen if you do not have the correct insurance on a vehicle and was in an accident, the state of Florida might impose penalties as if you did not have insurance or perhaps require an SR-22. You can check with the HSMV to find out for certain.