Even during the prime cruising months of June, July, and August, temperatures are generally fairly mild during this time, with average highs in the 60s and lows in the high 40s and 50s.

Alaskan cruises in the summer offer a climate that is best described as "variable" rather than "cold," though it is certainly much cooler than a Caribbean or Mediterranean voyage. During the peak season of June, July, and August, daytime temperatures in Southeast Alaska usually hover between 55°F and 70°F (13°C to 21°C). However, the perception of temperature changes drastically based on your activity. If you are standing on the deck of the ship while it is navigating near a glacier, the "glacial breeze" can make it feel significantly colder, often dropping the perceived temperature into the low 40s. Additionally, Alaska is famously rainy, especially in places like Ketchikan; a damp, rainy day at 55 degrees feels much colder than a sunny one. On the other hand, if you are hiking in Juneau on a clear day, you might find yourself comfortable in a t-shirt. The key to an Alaskan cruise is layering. You will likely experience four seasons in a single day. You need a waterproof outer shell, a fleece or light down mid-layer, and breathable base layers. While it isn't "arctic cold," it is rarely "tropical warm," making it a trip for those who appreciate crisp, fresh air and dramatic, misty landscapes.