We were there 2 weeks ago. Bring both. Juneau was in the 80's and the cruising was in the 50's. Layer is the word. Make sure you have a jacket and sweatshirt. deck was cool, definately poolside weather when we were in port. We did wear shorts in port. Depends where you are from. We are Floridians so 60's were cool to us. Hubbard glacier was cool. Needed a jacket and hood.
Anne