Palm Sunday was a beautiful spring day in Tokyo this year. I woke up at 5am and could not fall back asleep, so I decided to go to the 7am mass which was the earliest mass I have ever attended. When I was growing up occasionally my family and I went to 9am mass which I though was incredibly early and much preferred 10:30am or evening masses. So anyway bright and early I was at church and was surprised to see it was almost full. I usually attend the evening mass which is half or less full, so I guess the early masses are more popular at least in my parish.
There is no procession of the congregation from outside to inside the church at my parish since there is not enough room outside for people to gather. Other than that the mass was your average Palm Sunday mass. Back when I attended my first Palm Sunday mass in Japan I was happy to see the palm branches were exactly that, branches, not the whole thing but cut into nice sized sections for each person. In my home country the palms were just basically the branch divided up into a single palm leaf per person, so I happily keep my Japanese palm branch in water and it stays nice and green until at least Easter.
I should mention the vast majority of Japanese have no idea what Palm Sunday is so walking home with my palm branch people who saw me probably thought I was dong some kind of ikebana, or vandalising trees.