I saved this for future reference and thought you might like to read it; Majestic Mount McKinley plays hide-and-seek with Alaska visitors - USATODAY.com
As you can see in the article, only about 1 in 3 visitors actually get to see the mountain. Naturally, the day we went into Denali, it was drizzly and we never got to see it. The next day we were in Anchorage, about 200 miles away, and we could see the mountain very clearly. Go figure! But you'll hear the same story from many people - it's just one of those mountains that sometimes you'll get to see and sometimes you won't.
Like most people, we chose one big expensive excursion to do in Alaska - some choose the flightseeing tours, which are amazing if the weather cooperates. We did the helicopter/dog sled tour out of Juneau and it was awesome!
But there are many options available for some unbelievable sightseeing. No matter what you decide, it'll be fantastic and you'll be glad you did it. The important thing is that you do it as Alaska is one of those places you definitely need to experience.