This is a pretty cool place to go, in eastern Oregon about 30 miles or so due west of Boise Idaho. Easiest way to get there from the north or east is to fly to Ontario Oregon & then follow the Owyhee river south-southwest to the reservoir. The airstrip is about halfway down the length of the (man-made) lake on the west side. Kinda rough and 1800 feet long at 2680 feet elevation, so you have to pay attention.
We camped there a couple years ago in early June & got it all: hot, cold, windy, rainy, & then hot again. Had a good time. One couple even brought their funky little inflatable boat, at first I laughed at them but it turned out to be a lot of fun to paddle around.

Eric