Clark Fork River Fishing Report, May 18, 2026
The whole Missoula-area system is in spring-runoff mode. The Bitterroot peaked near 11,600 CFS on Friday 5/15 and has been dropping with the cool weekend; the Blackfoot is dropping from a 7,000 CFS peak (4,600 this morning); Rock Creek is around 1,500–1,800 CFS and still high; the Clark Fork is high and off-color, with the upper river fishing better than the lower. Tributaries open Saturday 5/16 this year. The week ahead clears up Monday with highs climbing back into the 60s — fishing should improve daily as flows drop and clarity returns. Best window most days is roughly late-morning through afternoon.
Conditions at-a-glance: High and off-color · visibility improving · water temp ~51°F upper, dropping from 3,000 CFS · upper river ~7,490 CFS, lower river ~16,000 CFS · Grizzly Hackle: 1/5
Warning: The lower river is serious volume. Above the Blackfoot confluence is fishing best right now; below town needs another week to clear. Tributaries do not open until Saturday 5/16.
Conditions. The Clark Fork has dropped 3,000 CFS in the last five days and is settling into fine fishing flows up high. The upper sections (Golds, Jens, Bearmouth, Beavertail) are mud-free with that glacial green clarity peeking through. The cold snap helped keep temps down up high. Below town will need more time. Fishing best on softer water — inside seams, slower buckets, transition water — where fish are holding out of the heavier current.
Best techniques.
- Dry-dropper is the go-to rig — Chubby or Water Walker up top with a TJ, Prince, or Jig PT underneath. Don't forget San Juans in red and pink.
- Nymphing with stonefly nymphs (TJ Hookers, double bead hare's ears, DBL Bead Stones, Front St. Stones, 20-Inchers, Zirdles, Blow Torches, Duracells, Prince Nymphs) and mayfly patterns like Pheasant Tails, Frenchies, and dark perdigons.
- Streamers in slightly off-color water favor darker, high-contrast patterns: black/purple/olive Dungeons, Gongas, and Woolly Buggers. Where clarity improves, mix in Sparkle Minnows, Masked Avengers, Goldies, Butchers, Foxy Cleopatras, and Mini Dungeons.
Hatches
Last of the March Browns, BWOs, Mothers Day Caddis, beginnings of the Fluttering Stone hatch, and a few straggling Skwalas and Grey Drakes. Look for fish to look up in softer water during warmer afternoons or under cloud cover. Good dry options: Purple Haze, BWO Comparadun, Last Chance Cripple, Parachute Adams, X-Caddis, Corn-Fed Caddis, and Chubbies / Hi-Vis Micro Chubby. Blackfoot River Outfitters' featured dries: Elk Hair Caddis, X-Caddis, Carlson's Purple Haze, Stranahan's Brindle Chute, Hi-Vis Micro Chubby, Plan B- Black/Purple.
The Fly Box
Nymphs: TJ Hookers, 20-Inchers, Blow Torches, Duracells, Prince Nymphs, Frenchies
Dries: Chubby, Water Walker, Purple Haze, Comparadun, Last Chance Cripple, Parachute Adams, X-Caddis, Corn-Fed Caddis, Elk Hair Caddis, Brindle Chute
Streamers: Woolly Buggers, Sparkle Minnows, Foxy Cleopatras, Mini Dungeons
Outlook. Wet and cool weekend in Missoula with highs in the mid-40s on Saturday and Sunday. Monday clears beautifully — highs climb back into the low to mid-60s through the week. Clarity continues to improve as flows drop; lower river still needs a week.
