Hey Dreampow, I was in Shibushi on the Oosumi peninsula, right on the border with Miyazaki. Such an awesome place - didn't want to leave!
Not sure if these are any good tokyo-dom, was doing some searching and found these - lol 'tramo-lando':
Indoor place in Yokohama - looks like it is all year-round:
-- S N O V A V ก l --
And this guy has a whole list of off-season training links for places around Japan:
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