The best advice I can give you is to pack and dress in layers in Alaska. You can have some fairly wide ranges of temperature during the day and rain is often a part of the day. So pack a waterproof jacket.
I'm not sure what category of stateroom you booked but most of the staterooms are quite similar. If you booked a balcony then others will be able to tell you if your balcony is covered, open or partially covered.
I do hope you did book a balcony for Alaska. It is (IMO) worth it.
Welcome to Cruisemates and have a WONDERFUL time planning for and sailing to Alaska.