I am planning on commissioning a couple of flannel trousers - a mid-grey and a charcoal grey - and would like some suggestions regarding fabric. I need these trousers to cover all of the colder months (fall through spring) in Washington, DC. While I suspect that, in a perfect world, I would have light-to-mid-weight flannel trousers for the shoulder seasons and heavier flannel trousers for the winter, we don't like in that (fiscally) perfect world. But in any event, Washington's winters don't get all that cold anyway (it's rare for highs to be in the 30s, although not unheard of). So ... what say the cognizati regarding the best weight for these bad boys? My initial thought is 12 oz. And what say you old hands with regards to "best" fabric at the recommended weight? I will most likely commission these trousers from W.W. Chan, by the way.