I don't think it's possible. Ouch, ew, oh no, what have I said.

If you're talking about being in a meditative state for more than an hour of physical time all the while out-of-body without returning to your body I don't buy it, I call looney tunes. It may
feel like hours, just as one may fall asleep and wake up 5 minutes later feeling that hours have passed. But to think that you can spend more than an hour without returning to your body is physically impossible -- unless your brain is unique in the way it stores these memories. I've had experiences that have felt like hours, yet when I return to the physical 30 minutes has passed. It's a strange thing.
Why am I saying this? What am I basing this on? The physical brain we need to actually recall these memories classes OBEs along with dreams and shuts down long term memory storage while in this state. So if you did manage to stay out for hours your recall of the event would be sporadic and dream like at best. It's physically possible, you would need to "wake up" every so often and recall the event while in the physical for it to be stored long term without losing it.
I know I'll take some flak for this and I'm not trying to flame, it just doesn't seem legit to me.
At this moment I don't remember any of my dreams except for bits and pieces of a few special dreams, I don't even remember what I did yesterday

but I can recall my few long OBEs and dozens of short OBEs (out of hundreds) in detail so I don't think your theory is correct but as I said in all of them I had help from many guides and it wouldn't be so easy to stay there for that long and remember everything like that if it wasn't for their energy. It's your energy level and experience that raises your awareness in such experiences so theoretically if someone has a lot of energy and focus I don't see why he shouldn't be able to do this on his own.