Again, it really depends, they have been HORRIBLE in the mountains this year.
http://cascadeclimbers.com/forum/ubbthreads.php?ubb=showflat&Number=1140661"But, it was the mosquito apocalypse. We kept thinking that if we got higher, above treeline, the mosquitoes wouldn't be there. But they only got worse and worse. The very air was thick with them. They were in my eyes, in my nose, in my mouth. At any given moment, there was at least 50 of them biting me. Looking over at Allie, she constantly had a cloud of at least 100 around her.
Despite the blistering heat, we put on our hardshells to at least partially protect us from the bugs. Between my pants and my shell and bugspray on my face (we didn't have enough to totally cover our whole bodies in it), most of my body was covered... except my hands and ankles. Allie was not as lucky, the bugs could bite right through her pants. Bleeding and itching from thousands of bug bites, we ran away from the base of the Paisano route and headed up to Burgundy col, thinking the breeze there might clear them away. They were slightly better, but we were still getting hundreds of bites per minute."
Uh yeah, so just stay in safe, bug-free seattle.