High summer, high reward.
Right now, the Bighorn is running at a sweet 1,490 CFS—perfectly clear, totally wadeable, and just a touch higher than a few weeks ago, according to Fly Fish Food’s latest report. The catch is that it is pushing 94°F and more out there, and the afternoon moss is creeping in below 3-Mile.
If you want to trick these fish, you need to play the clock, not just the hatch.
- The Dawn Patrol (6:30 AM – 9:00 AM): Sleep when you’re dead. Get to the slow pools near the dam while it’s still cool. Nymph some tiny BWOs and midges before the sun bakes the water.
- The Golden Hour (9:00 AM – 1:00 PM): This is why you came. The PMD hatch hits the riffles hard. Look for dimples in the flats, tie on a dry fly, and hunt individual risers.
- The Siesta Shift (1:00 PM – 3:00 PM): When the hatch quits and the heat peaks, pivot. Slap hoppers and ants right against the shaded cutbanks where big browns go to hide from the sun.
- The Happy Hour (6:00 PM – 8:00 PM): Let the inevitable afternoon thunderstorms roll through. Once they clear, the evening Caddis bite along the grass is pure money.
Match the hatch or trigger a frustration bite. Here’s what’s getting eaten:
- For the Morning Hatch: Tungsten Split Case PMD (#20), Parachute BWO (#22), or Juju Baetis (#22).
- For the Afternoon Heat: Bionic Hopper (#12) or Bionic Ant 2.0 (#16) dropped inches from the dirt.
- For the Evening Rise: Corn-fed Caddis (#20).
- For the Meat Eaters: Coffey’s Sparkle Minnow (#6) always has a chance.
The Bottom Line
Don’t waste your energy blind-casting the middle of the river in the afternoon heat. Focus your morning on the riffle seams near the dam, hunt specific rising fish during the lunch-hour hatch, and spend your afternoon pounding the banks. If the sky turns black after 2 PM, get off the water, grab a truck beer, and wait for the evening caddis madness.
Editor’s note: Corrected an overlapping time window: the 'Siesta Shift' now runs 1:00 PM – 3:00 PM to follow the Golden Hour sequentially.
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