diver86,
Given your location and time constraints, here's some info.
With a long weekend, from MS (not sure where in MS), Pensacola is your first, best bet. Here you have charter opportunities (weather permitting), shore diving possibilities and great food, fun and lodging.
Next option are the springs around Ponce De Leon. 2 to choose from, each with much to recommend.
Beyond there, Destin, Panama City and Port St. Joe. You won't get farther than that on a long weekend, and those three will be a bit of a stretch even so. You won't make Ft. Laud., the Atlantic or the Keys on a dare.
Sooo, back to Pensacola, we have a number of charter operations that will be happy to have you aboard, weather and numbers permitting. There are several good shore dive options for either of the likely weather scenarios, and it's a close, nice, affordable destination for a long weekend. Good stuff for kids and family, if you've got 'em and a fun place if you don't.
Send me a PM, or call. I'd be happy to share more info on the options, if you are interested.
Capt. Jim
Dr Dive
Dr Dive Pensacola, FL - Home of the USS Oriskany
drdive@drdive.com