This jacket is not heavy but it sure is warm.  I've worn this jacket without a rain/wind resistant jacket on top in temperatures in the teens and twenties and it has kept me warm for a while until the wind started blowing.  The only thing I don't like about the product is that it is difficult to zip up at times because the bottom zipper rides up a little bit when unzipped and if you don't check and pull it down you won't be able to zip up.