Big Thompson River Report

Big Thompson River Report

6-19-2026

Flows are up a tad, about 5 CFS. Currently, you'll run into overlapping hatches with water temps on the rise, and the fish can be fairly surface orriented all day, especially during periods of cloud cover. Most techniques are working right now, but we've still usually been starting out with dry droppers. The lower canyon has some higher flows, but is fishing good as well. FIsh can be with the warmer water temps in some surprisingly fast water, so be sure to pick the water apart. Observed hatches are Midges, and BWO's with some Caddis, Yellow Sallys and PMDs.

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For dries, use a Chubby Chernobyl, Angee's Knobler, Fool's Gold Sally, AR's Adult PMD, Hi Viz Quill Midge, No See Um Hi Viz BWO, Peacock Cluster, Griffith's Gnat, AR's BWO Adult and Emerger, Fin Fetcher Caddis, Superman Caddis, and a Hot Mess Midge.

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For sub-surface, use a Juju Baetis, RS-2, Puparazi, Zebra Midge, Tailwater Sow Bug, AR's Spanish Bullet, America Nymph, Crust Nymph, Lil Bit, Tung Stud, Angel Case Emerger, Juggarate Chocolate Baetis, Kyle's Yellow Sally and a Hogan S&M Nymph.

Guide Rating

5/5

Weather Experienced

- Temperature: Mid 70's

- Wind Conditions: Breezy

- Precipitation: None

Water Observations

- Water Temperature: Lower 60's

- Flow Level: 129 CFS

- Water Clarity: Light stain

About Big Thompson River Fly Fishing

Starting as a mere trickle on the east side of the Continental Divide, inside Rocky Mountain National Park, the Big Thompson flows from Forest Canyon Pass near the top of Trail Ridge Road through Forest Canyon. As small drainages offer additional snowmelt, the Big Thompson picks up volume, turning into one of Colorado’s finest streams.

The Big Thompson becomes fishable at Moraine Park in Rocky Mountain National Park, about six miles downstream of its headwaters. It’s there at Moraine Park, where the river splits into numerous braids and channels, that fisherman encounter the river’s first public access. Trails leading up and down the river from that point will lead you to great flyfishing experiences.

Moraine is a wide-open area, but the Big Thompson’s banks are lined with willows. It’s typical small stream conditions, and the river is filled with, you guessed it, brook, brown, and cutthroat trout in the 6- to 12-inch range. They’ll readily take a variety of general attractor flies.