The best way to take care of this stuff in your absence is to find the proverbial cool, dry place, which might be a hard thing to do in Beaumont, Texas. One possibility: If you plan to store any household goods in a rental-storage unit, find one that's multi-story and has inside units, then rent an inside unit on the bottom floor. That will have the least temperature fluctuations, and should stay pretty dry.
Otherwise, don't leave the bag or tent in stuff sacks. Shake them out and store them loosely in large, cotton or mesh bags. You want the bag to be able to breath to adjust for humidity, and you don't want to compress the down any more than just a little. The pack you can just hang up on the wall. It'll get a little dusty, but no harm in that. The main thing is you want to minimize humidity. The big enemy is going to be mildew, with especially thrives in warm, damp climates in the South. But, if you take a few reasonable precautions, everything should be fine when you return.