judging by your SN, you have an SS... that being said, yes you can adjust your rear air bags... if you look through your rear wheel spokes, or eve take the wheel off to see.. there are sensors that you can loosen their mounts, and readjust them, therefore making the rear end go higher or lower...
here is a write-up/how to, on tbssowners.com... literally takes you 5 minutes to acomplish this...
I was lucky to use that method bottom out both sensors and I came out with 1/4 inch rake. Took me longer to get to the bolt than the whole lowering process
no, it wont efffect your driving in the winter.. if you were dropping say 2+", then yes, the ride would be a bit bouncy and annoying... but with just a 1/4" to an 1", you wont notice much differnece..