http://www.rmiguides.com
They required we arrive a day early and go through a daylong training/qualifying climbing school before attempting the actual 2-day climb. This is a good idea because it weeds out the people who really have no business being there.
Overall, the whole thing was a good experience, but we never made it to the top. The first day of the climb, it was raining cats and dogs - we got about 1/2 way to the shelter where we would spend the night and people started falling down while slogging through the snow. The guide used his professional good judgement and rightly called the climb off and I never got around to trying again.
Yep. The weather is unpredictable.
My house is on a bluff on Puget Sound and our street is aimed right at Mount Rainier. When I get in my car each morning, sometimes you can see The Mountain. Most of the time, you can't.