The Oregon Brewers Festival starts Thursday the 26th and runs through Sunday the 29th.
If you prefer drinking beer to standing in lines in ridiculously hot weather, get there early in the day. Taps open at noon so you should start drinking at noon. Arrive at least before 5pm on Thursday or Friday. If you can’t get to the festival by early afternoon on Saturday or Sunday I wouldn’t bother; a few blocks away at the Yamhill Pub the Pabst is only $1 all day Sunday!