70, to me is good take a walk weather, but I would always have a sweater with me at 70 degrees. I know I know, I'm a wuss.
TIS
I can't wear more than a t-shirt past about 65 (if it's sunny) and I don't consider myself warm blooded or anything. About 40 I can see the need for a sweater or light coat. I think I am just built to live in a cooler climate. I like the beach and all but I prefer cooler temps.
Long as I remember The rain been coming down. Clouds of Mystery pouring Confusion on the ground. Good men through the ages, Trying to find the sun; And I wonder, Still I wonder, Who'll stop the rain.