August and September ... Some cruise lines, such as Holland America Line, have formal evenings. It's not required to dress up, especially in Alaska, but many women choose to wear cocktail dresses ...

The Alaska cruise season runs from late April to September, with July and August ... Alaska’s weather can be unpredictable, so it’s good to wear layers. Bring a waterproof jacket and wear ...

Not only will the destination and weather factor into what you should wear on your cruise ... Costumes are suggested for Halloween cruises between the end of September and October.