Big Thompson River Report

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Big Thompson River Report

7-13-2026

Flows are surprisingly steady, which is great news! Water temps in the middle to lower canyon can get hot, and with the current heat, carrying a thermometer isn't a bad idea, as the upper stretches may start getting a bit warm wuith the dam doing a top release of water. Fish are pretty spread out right now, so hit any fishy looking water you come across. Dry fly fishing has been good, but slows down a bit midday, which is when we've been switching to a dry dropper. Observed hatches are Midges, BWO's, 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: Upper 80's

- Wind Conditions: Breezy

- Precipitation: None

Water Observations

- Water Temperature: Lower 60's

- Flow Level: 96.20 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.