American Apparel jackets in the summer yay or nay?

Photo`s shown are not my own, source links below

I love my AA jackets, there warm and comfy and dont forget they have the cutest and most vibrant colors. I just wonder if its appropriate to wear such a warm jacket during the summer; I always think that it will get colder at night so I should put one in my bag just in case I still out late. Or is it better to just put the AA jackets in hibernation and rock thinner jackets instead.
Is it a yay or a nay?

http://www.starstyleinc.com
jackets

Source link: http://www.thisnext.com