Not many rivers to choose from these days, I did forget to mention the North Fork Nooksack, Horseshoe Bend section, is also a great class 4 option right now!
Sauk levels are hard to guess into the summer. The main gauge is downstream just a couple miles from the mouth of the Sauk which includes major tributaries like the Suiattle and Whitechuck. The other gauge is just upstream of the Whitechuck, and neither Suiattle or Whitechuck have gauges of their own. So for the class 3/4 stretch from Whitechuck down it's touch to guess what the actual flow might look like, it's nice to see over 1000cfs above Whitechuck and several thousand for the lower Sauk gauge. Sorry for the late response!
