The average temperature in February in Tokyo is high of 10℃ (50℉) and low of 2℃ (36℉).
If you are traveling with public transportation, you may not have to wear so much.
It was around 5-7℃ (41-45℉) today during the daytime. I wore T-shirt, Sweater and Down Jacket. It was not windy at all so it was totally okay not to wear scarf or gloves.
When you walk outside, it might be better to have a pair of gloves, scarf and/or a hat.
Have fun in Tokyo!