I am planning to go to Taipei & Hualien mid of November.

May I know what is the weather in Taipei & Hualien in mid November? I was thinking of staying minsu in Hualien. Should I stay for one night or 2 nights if I plan to visit Taroko National Park, Tunnel of Nine Turns, Swallow Grotto & Mystery Valley? Should I purchase the train tickets in advance or can I purchase when I reach Taipei?

Any summer clothes that I can still find in Nov?

Sorry for having so many questions.