Last time I've been there was close to two years ago, so pretty much around February as well. I stayed as central as possible, right next to Plaza de la Merced, which is a good hangout spot. You'll meet some Skateboarders there for sure. Weather was always great.
The whole marina area was still skateable, but I never met locals there — some things were a little rugged (the area with bank / wallride), but there aren't too many tourists strolling around as it's going to be off season. The curved ledges along the avenue east of the main plaza and all that stuff should be always good to go.
At the time there was a DIY in the old riverbed which was a really cool hang out spot as it was still pretty central, too, not sure if it's still there, curbs / legdes, flat rails, all built super solid, you'll meet people there. I remember there was also CAC, an arts museum that had some blocks to play with and super perfect flat ground. As the center is pretty small and the ground is always good, you can cruise everywhere in no time, so just discover.
Enjoy, I'm sure you are going to have a great time.