I was in Alaska once. I saw what I thought was a Crane Fly. It looks like a very big mosquito (1+ inches long). The AK native that I was with informed me that I was looking at a mosquito and not a Crane Fly. I never did figure out if he was yanking me around or not.
I developed a great love for Dragonflies on that trip.
In the spring, which is usually in May, the first mosquitoes come out, and they are the same ones that were around at the end of the fall. They overwinter, frozen solid, I suppose, and thaw in the spring. Big, yes, but slow. The spring generation is small and quick, deadly in numbers.