Clark Fork River Fishing Report, July 17, 2026

2026-07-17 (July 17, 2026)

Regional summary

Not much has moved on the calendar in the three days since the last report, and yet the season keeps inching forward. Every valley gauge is a notch lower than it was, the water keeps clearing, and the bug board has finished its handoff: the big stoneflies that carried June are essentially done, and trout have settled into a steady summer diet of PMDs, Yellow Sallies, caddis, Green Drakes on the gray days, and the first real wave of terrestrials. The one variable running the whole show is heat. Mornings still start cool and friendly, but midday water is now creeping into the upper 60s and low 70s on the valley rivers, so the productive clock has slid hard toward early and late. The other new wrinkle is a regulation change worth knowing before you load the boat: the Blackfoot closed to floating from Weigh Station down to the I-90 bridge on July 15, running through October 31. Carry a thermometer, start at first light, get fish in and released quickly in the warm afternoons, and check Montana FWP for restrictions before every trip, since nothing was posted when the shops filed but a hot week can flip that overnight.

At a glance: Dropped into good summer shape, best through and west of town | slightly off color, improving | ~70°F midday | ~2,440 CFS above Missoula, ~3,940 below (live USGS, down from ~2,670/4,510 last report) | GH rating: 3/5 | Best window: early and late

Float hazard: new tree down between Turah and Sha-Ron. about half a mile above the Clark Fork and Blackfoot confluence. Details are still thin, so call Blackfoot River Outfitters (406.542.7411) before floating that stretch.

The Clark Fork has kept dropping into genuinely good summer shape, with clarity improving and the fishing running consistent. The upper river above town is going low and weedy, but the water through Missoula and west of town remains the strongest, most overlooked hand in the valley this time of year. Fish are stacked in the soft, defined water: grassy banks, inside bends, foam lines, side channels, drop-offs, and the seams beside the heavier current. First thing in the morning, look tight to the banks for nocturnal stones before the sun gets on the water. Like the Blackfoot, the Weigh Station to Sha-Ron float is closed through October 31, so check your access before you launch.

Best techniques

• Search the soft edges with a dry-dropper. Put a high-floating golden or a Chubby Chernobyl, Water Walker, or Plan B up top in #8-12 tan, gold, or purple, and run a Jigged Hare's Ear, Perdigon, Psycho May, Caddis Pupa, or PMD nymph three to four feet below.
• Nymphing is the reliable midday play while the last color clears and the sun is high. Lead with the stonefly crowd (Pat's RLs, Twenty Inchers, TJ Hookers, Zirdles) and follow with Frenchies, Jig PTs, Split Case PMDs, and Prince nymphs as the day matures. Work the eddies, riffles, and buckets.
• The dry day runs on a clock: PMD spinners in the morning slicks, then sallies, drakes on gray light, and caddis plus a single Sparkle Dun, Corn Fed Caddis, or Purple Haze into the evening. Do not overlook streamers here; the CF has been fishing yellow, white, and olive well, with a Kreelex, Barely Legal, or Mini Dungeon worth a pass along shaded banks. Grizzly Hackle keeps the deepest cripple and spinner bins in town if the evening fish turn technical.

Hatches

Golden Stones winding down with nocturnal stones creeping in early, consistent PMDs, Green Drakes on gray days, Yellow Sallies, loads of caddis with evening activity, and the first ants and beetles.

The Fly Box

Nymphs: Pat's Rubber Legs, Twenty Inchers, TJ Hookers, Zirdles, Frenchies, Jig PTs, Prince Nymphs, Split Case PMDs, Psycho May, Caddis Pupa, Jigged Hare's Ear, Perdigons

Dries: Chubby Chernobyls, Water Walkers, Plan Bs, Golden Stones, PMD Spinners, Green Drakes, Yellow Sallies, Elk Hair Caddis, X-Caddis, Corn Fed Caddis, Sparkle Duns, Purple Haze, Parachute Adams, Ants and Beetles

Streamers: Sparkle Minnows, Mini Dungeons, Peanut Envy, Sculpzilla, Thin Mints, Woolly Buggers, Kreelex, Barely Legal

Outlook. Hot with a heavy thunderstorm chance today and more heat Saturday, then 80s with a mix of clouds and sun into next week. A storm cell could briefly cloud the water, but the cloudy windows help the dry-fly bite. If the drop holds, this is the week to hunt the Clark Fork's soft water while everyone else chases the prettier rivers.

Sources and Thanks

Shop	Report date	Coverage
Kingfisher Fly Shop	July 17, 2026	All four rivers (freshest)
The Missoulian Angler	July 16, 2026	All four rivers
Blackfoot River Outfitters	July 10, 2026	All four rivers
Grizzly Hackle	July 10, 2026	All four rivers
Lightweight Fly Shop	July 5, 2026	All four rivers, consolidated weekly