The climate varies widely throughout USA's largest state, with a climate more comparable to Northern Canada than the rest of the States. Most people visit between May and September, when the days are long and the temperatures are moderate. The longest days occur around the summer solstice, June 21, when in the southernmost Inside Passage, around Ketchikan, you can experience 18 hours of sunlight.

In south central Alaska, Anchorage gets 19.5 hours of sunlight. Fairbanks in the Interior has 21 hours, and north Alaska has 24 hours of sunlight. Winter brings 24-hour darkness only to the part of Alaska above the Arctic Circle. Anchorage, Juneau, Fairbanks and the rest of the state all get some sunlight for a few hours each day. The climate in Juneau and the southeast panhandle is wet and warm with milder temperatures in the winter and high precipitation throughout the year. Anchorage and south central Alaska is mild by Alaskan standards, mainly due to its proximity to the coast. It experiences less rain as the southeast of Alaska but more snow.

Western Alaska is influenced by the Bering Sea and the Pacific Ocean. The inland sections are warm in the summer and cold in the winter. The interior of Alaska experiences the most extreme weather, with some of the hottest and coldest temperatures in Alaska occuring around the area near Fairbanks. Summer temperatures can reach about 34°C (93°F) and in winter the temperature can fall to about -52°C (-60°F). The extreme north of Alaska has an Arctic climate with long, very cold winters and short, cool summers.