Simply put, yes you are facing a felony in Florida. Three priors from any jurisdiction usually qualify as priors (with some very limited exceptions). You need to get an attorney in your area now to fight this. Good luck.
A fourth DUI in any amount of time is a serious crime in Florida with a possible lifetime license suspension. It is critical that all your potential defenses are analyzed and asserted in a timely manner.
There are many excellent DUI lawyers in Jacksonville - I suggest you contact a few as soon as possible and make a plan to have your interests aggressively represented. Feel free to contact my office. I can explain the process and recommend other attorneys in town you may also want to speak with.
I wish you the best of luck.
Yes. You are facing a possible felony filing, however there is a chance that the state could opt to file it as a misdemeanor. We have succesfully negotiatated with the state in prior cases here in Jacksonville to avoid felony filings. It is of course up to the individual state attorney handling your case. But keep in mind, even if they do file it as a felony, it is not over. The state still must bring forth a "provable" case and get over many hurdles in order to secure a conviction.