You'll see shorts in winter. Don't know how those people do it... my chicken legs don't care for it.
There's plenty of water all around in winter... just be sure to melt it first. Eating snow to hydrate is tough/rough on the body, or so I've heard. Haven't had to do it myself, but it makes sense.
Phones - Don't count on having service off the beaten path, unless you're on top of a mountain which is within view of a populated area/highway (which is why all maps best be downloaded onto your device). The best, or worst case, device to have is a PLB, but the casual explorer typically doesn't carry one. I've heard you can rent them. I've also heard avalanche backpacks have them built in and are triggered if the pack has to deploy... pretty cool. I've not become so adventuresome that I have such things... the desire is there, but I haven't acted upon it. I've been toying with the idea of getting my HAM license, if for nothing else than to have a radio with some reach (particularly if hiking). My problem is I'll leave my "plan" with someone (if I'm going out alone), get bored with that plan, then deviate to find new things. Hasn't left me in a pickle yet, but it's just a matter of time.
I like photography, so getting out to see the big horned sheep in fall and winter is fun. I usually combine that with a flexible ski schedule, so that if I happen upon the sheep when heading to the ski area, then I'll spend as much time as I like taking pics.