Contrary to popular belief, while temperatures do go down on average as you go further north, the really pronounced difference is how much it varies between its extremes. Realize that in the summer in these northern places, the sun is shining (or at least in twilight) past midnight, and comes back up very early in the morning, only a handful of hours later [1]. It actually gets quite warm [2].

[1] http://www.alaska.org/weather/daylight-hours/whittier/june

[2] http://weatherspark.com/averages/33093/6/Whittier-Alaska-Uni...