Any advice for a 13 hour layover at HND? I've never been to Tokyo before - flying JAL J. That's too much time to sit around in a lounge I think - I'm assuming JAL's J lounge has showers so I can at least freshen up before my onward flight to LAX?

What would you do if you had that long a layover - do they have lockers I could stash my luggage in for the day? Take the train into Tokyo and have lunch? I get in at like 6 a.m. on JL and my next flight (JL metal operated by AA) doesn't depart until 7:10 p.m. I don't see any other options on AA/JL out of NRT or HND to depart to any destination on the West Coast so I think I'm spending the day. Thank you!