Why does Pantín feel different morning to afternoon?

Usually because local wind and tide have changed, not because a new swell arrived. The NW-facing beach takes the afternoon breeze more directly than a sheltered cove, and the tide running over the bank changes the shape under your feet. If neighbouring beaches also jumped in size, the swell filled in. If only Pantín got bumpier, start with wind and tide. Check whitecaps in the bay, the tide line on the sand, and whether Marnela still looks organised.