Fly Fishing Greys River

The Greys River is one of Wyoming’s most underrated yet rewarding freestone streams, offering fly anglers miles of productive, remote water surrounded by dramatic mountain scenery. Flowing north through the rugged Wyoming Range, the Greys meets the Snake River near Alpine, making it one of the key tributaries feeding the famed Snake system. The river winds through a narrow canyon and opens into broad valleys, featuring varied water types — from fast pocket water to long glassy runs and deep cutbanks. With minimal development and easy roadside access along Forest Service Road 10138, the Greys River is a paradise for adventurous anglers looking to explore off-the-beaten-path fisheries.

Fishing the Greys River is all about variety and solitude. Native Snake River Fine-Spotted Cutthroat Trout dominate the system, but healthy populations of Brown, Rainbow, Brook Trout, and Mountain Whitefish provide a mixed-bag experience. The Greys fishes best from late June through October, once runoff subsides. Stoneflies, Yellow Sallies, Caddis, PMDs, and terrestrials make up the bulk of the summer hatches, and dry-dropper rigs or hopper-dropper combos are especially productive. In fall, streamers bring out the larger browns, especially in the deeper pools and near woody debris.

Because the Greys River is so remote, it sees relatively low fishing pressure compared to other Wyoming waters. Its proximity to Jackson (under 1.5 hours away) makes it a great day trip, but many anglers opt for multi-day camping and fishing missions along its 50+ miles of accessible water. The USGS gage near Alpine provides real-time flow info, with optimal wading conditions typically between 200–600 CFS. Whether you’re casting dries to rising Cutthroat in July or stripping streamers through undercut banks in October, the Greys River delivers a wild and memorable fly fishing experience.