Best weather: From June through August, expect highs in the low to mid 20s. May is quite dry, but by August the chance of rainfall increases to 50 percent daily.
Less crowded/lower prices: Go in May or June to spot newborn animals in Denali National Park. In August and September, prices can be up to 25 percent lower than in busier months.
Book your trip: A year in advance for cruises or six months out for land vacations to ensure the best rates and availability.
One more thing: To see the northern lights, go in January, February or March—and bundle up!