I gave up on trying to dress correctly for the weather years ago, Boise ID is about worthless to have a weather forecast as its likely to do something entirely different. The only place ive been that has more unpredictable weather than Boise is Laramie Wyoming where I once saw the temp go from mid 80's to below freezing and start sleeting mind you this was aug. There was a quite a few days the temp change was more than 60 degrees how the hell do you dress for that change.

What I do is I keep shorts and a T-shirt at work year round, its 28f and snowing right now but two weeks ago it was highs in the mid 60's so its easier to have a completely different change of cloths for when I need it.