The smallmouth bass started out with a reasonable bite by the end of April with a few streaks of warm weather to so spur things on. The shores and side ponds of the Columbia River between Bonneville and McNary Dams started well and continue to produce great bass fishing. Most of all, popper fishing is in tall order and raising big bass is definitely probable. I noticed the weeds are choking some areas but no worries, look for the open pockets (even as small as a bathtub) and cast to it. Right now, intermediate sink and floating lines are the ticket as bass continue to feed near shore and are spawning. Fly choice is pretty simple, anything white or black does the trick. If your fly mimics a 2-4 inch bait fish or crayfish, it will produce too. I'm a big popper fan myself, so, I tend to fish on top most of the time. Killer popper time is the first 1 1/2 hrs of daylight and the end of daylight! I don't think popper color is a big deal, but I like, red/white, green/yellow, and black/yellow. the popper body is just about the size of an acorn or slightly larger.
I prefer fly fishing from a boat but there are plenty of side sloughs and ponds along hwy 14 on the WA side and I-84 on the OR side. Float tubes provide a lot of versatility to get into tight places. Bass fishing should be good through most of the summer and the bite will become crazy again when the juvenile shad begin their out-migration.
Wishing the best in your fly fish pursuits,