Should I TA next semester?

I'm currently TAing for my advisor in a Master's program - I've started my thesis and plan to be done by the end of the calandar year (December). I want to go on to a PhD program, and my advisor has been a lot of help to my work and such. This fall I have to take an obligatory "Thesis Supervision" course as I finish submitting it. I commute to campus (in New York) from where I live (in Connecticut), it's worked out so far as I only go in once or twice a week. This semester, I'm only going in to TA, or for meetings and such.

My advisor emailed me yesterday asking if I wanted to TA for him in the fall and spring, saying he knew I might not be enrolled in spring but thought he'd ask. The problem is, this fall it would add an extra day of commute strictly for the sake of the class I would TA. The stipend would cover travel for that day and part of the day I have to be there for Thesis Supervision. I'm not sure what my plans are work wise for fall yet. I do videography on the side, and I'll be applying to other grad programs, I'm sure there will be other things to keep me busy.

Mostly I don't want to disappoint my advisor. So is it ok for me to turn down the TA offer because I'm not sure if it's the best thing for my schedule?