We were in Tokyo the 5-15th ish last year, weather was pretty good, got HOT our first couple of days, but once the sun was down it was FREEZING. Closer to the 15th we had some chillier park days, simply a thin pullover underneath a tshirt with full length pants was good enough, threw on a warmer sweater at night, and GLOVES! Layers are key
Shanghai was pretty warm for us, we were there Oct 30- Nov 4th, days were fine in a tshirt, needed more layers after sundown