Seems your son was a mirror of mine. Threw 84MPH after Soph year and he only played legion his rising soph and junior seasons. We started by making a list of schools that would fit academically and for baseball. We initially focused on D3. We reached out to these schools, with a few hopeful D1, sending videos and attended their camps. But his velo kept climbing and he eventually committed D1. He received numerous offers, all based on our list and the camps we attended.
However, we had the luxury of being in the northeast and all schools fairly local, as my son didn't want to go far. It was easy for us to go and be seen. I think your biggest constraint will be wanting to play outside of CO. Members here have much more experience, but I think the majority of CA schools, have CA players. You will need to work extremely hard to get on their radars, when they have similar kids in their back yards.
There's a lot of time between now and the summer, when you start on your travel teams and MAYBE get in front of the schools you desire. Make a video of your son, send out to schools, get on the coaches radar. You will need to start visiting schools, just from an admissions perspective, see if coaches will meet with you, etc. I always tell people, getting my son recruited was a part time job, and you need to work real hard at it. Now, if he was throwing 94, that's a different story...