I think sometimes people forget that there are regional variations on both sides. Someone coming from Florida and California may find it generally cooler here. I'm from Wisconsin, and don't miss the frigid winters, don't need the heavy coat, but do need the layering to protect from the damp. I love the cooler summers, and generally speaking, even if it got hot for me, I wouldn't wear shorts the way the I wore them in the US - as in, everywhere! Because where I live now, I just don't see it being done the way I did it in Wisconsin - I wear more skirts though.
So, it doesn't answer the original question, but I didn't bring any heavy coats with me, and I brought fewer summery things. I've been here 3 years now and still wear a few of my old American clothes, but have mostly replaced my wardrobe as I've gone along (and gained and lost weight!!). Replacing my wardrobe has included buying shorts, tank tops and strappy sandles, as well as woolen stockings and a waterproof!