Alaska: Cruise to Alaska
High season: June through August
Quirks and Perks of Sailing in Season: temperatures are at their warmest at 50 to 70°F. The further into summer you are the better you can see wildlife on the various expeditions. The downside is that the demand is very strong and you need to book months even years in advance to get the best land and tour packages. Keep in mind that there are so many sailing ships in Alaska now there's a tremendous amount of congestion in the small town ports.
To minimize these masses select a ship the sales during the week. For pricing advantage the northbound glacier roots tend to be cheaper than the southbound.
Low season: May and September
Quirks and Perks of Sailing in the Season: shoulder season perks include small crowds and cheaper prices on cruise because of the gamble that you take on the weather and it is only in the 50s and 60s and there's a possibility of snow. May sailings typically encounter less rain than the summer cruises and the scenery is arguably more beautiful with the snowcapped mountains. September cruisers benefit from the end of season souvenir bargains and they possibly can catch the northern lights. Just a few caveats though-shore excursions have a greater chance of being canceled than in high season especially the boat and helicopter tours. Additionally Denali National Park is been known to close in September due to snow.