Online
Unfortunately, no. Total screw-up in the planning process. Unless you fly out on Tuesday mornings, the lots are generally full. Thursday-Sunday its basically shut out. (Unless you want to park in the old garage by the old terminal and take a 15 minute bus ride - no thanks).
I did discover that you can reserve a spot on their website and then park there even if it shows 'full' but I usually just uber at this point.
Last time I gave the guy $20 guarding the entrance since website showed 15 open spots. Lol