What to wear to Harbin at the end of April?

With the current changes, the temperature at the end of April will be around 20, or even higher ... the temperature difference between morning and evening is relatively large, about 10 degrees. Clothes can be increased or decreased as appropriate. It is suggested to add a short coat and a T-shirt. People who are weak should wear a sweater, plus a jacket and a book. However, the temperature difference between day and night is large, so pay attention to increasing or decreasing clothes.