Should weather systems impact gameplay?

We've talked about weather systems and day/night cycles before, although generally MMOs and gamers seem to think of them mostly as cosmetic features that are fine to have as long as they don't get in the way. But what if they do get in the way? What if weather actually has an impact on your character and the game world?

What if a pass got snowed in so that you couldn't reach a certain area? What if whiteout conditions kept you from seeing that face-eating monster 10 feet away? What if wind gave your character an extra bounce in his or her step if it came from behind or actually slowed you down if you were facing into it? What if lakes dried up in drought or lightning could strike metal objects (like, um, your plate mail)? Would it be more immersive for you or just more annoying?

Seeing as most of the potential ways that weather could interact with us are negative, this might be a silly question. Still, I'm putting it out there: Should weather systems impact gameplay, and if so, how?

TH

YES PLS in all realistic ways possible!!