Flows are at average for this time of the year on the upper reaches and is only around 10-12% above average on the lower reaches. What is...
Its August 10th - Think dry flies. But don't ignore nymphing.
August 10, 2017
First Report for December - Think Midges, BWOs, and Eggs
November 30, 2017
Cooler temps in Snake River country but we are still getting many days in the upper 30s to upper 40s and a respectable amount of surface action in the afternoon on midge and blue-winged olive imitations. Slow water targets at the margin, tailout, and inside head of riffles are the prime water types to hit. There is also decent activity in eddies and side channel confluences, although not as consistent as you will find in the vicinity of riffles.
Double nymph rigs and dry-droppers can produce throughout the day, although the activity is definitely better in the afternoon. Chironomid larva and pupa are working best. Egg patterns have been producing through November but expect this to continue through December as the whitefish spawn continues. Target riffle tailouts primarily, and go with as long of a drift as you can before a take.
Much the same story as what is being experienced on the Snake – Cooler temps we still have days in the lower 40s to lower 50s and decent dry fly action in the afternoon. Riffle tailouts, Seams, eddies, and flats are all fishing well with midges and blue-winged olive imitation (noticeably more blue-winged olives on the South Fork than on the Snake). Expect this action to start around noon and build until 3pm until falling off around 4:30 to 5pm.
Nymphs are producing throughout the day with OK action in the morning and much better action in the afternoon. Dry-dropper rigs are working best. If you go with a double or triple rig, keep your leader length at roughly five to six feet from line-leader joint to the trailing pattern. Target riffles, seams, and flats. As on the Snake, egg patterns should continue to produce in riffles on flats throughout December.