The Bighorn is looking pretty darn dialed right now, with clear water rolling out of Yellowtail Afterbay at 1,850 CFS and trout feeding well from breakfast through happy hour. This report is by Fly Fish Food from September 13, 2026, and the big headline is caddis: PMDs and midges can keep rods bent through the morning, but once the afternoon warms up, #16–20 black and tan caddis become the main event, especially around seams, shallower runs, and weed edges. As the report puts it, “the best dry-fly action will develop between 1 and 5 PM as caddis get active,” so save some enthusiasm for the afternoon risers. Early birds still have a good reason to launch before 9 AM, when nymphs and sculpin-style streamers can tempt bigger browns along deeper runs and undercut banks, while patterns like Frenchies, Pheasant Tails, Juju Baetis, sowbugs, and Sparkle Minnows round out a very fishy fly box.
With sunshine pushing temperatures toward 81°F before possible rain and wind arrive, Sunday afternoon looks like the sweet spot to park the boat, watch the water, and let the Bighorn tell you when it’s time to tie on something tiny.
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