Even in the summer - longest day of the year - Anchorage will see sunset/sunrise. The time in between sunset/sunrise will be a twilight time. By the time you get to Fairbanks - some 250 miles further north - you will be in the Land of the Midnight Sun. The summer temps will run 55F to 75F in Anchorage. Being its interior, Fairbanks can get considerably warmer in the summer........and we all know about winter in Fairbanks!!
Man - I miss the times in Alaska - they were some of the best experiences I will ever have.