Greys River Wyoming Hatch Chart
Western Wyoming, flowing north through the Wyoming Range in Lincoln County before joining the Snake River near Alpine. The Greys River is one of the most remote and unspoiled wild trout streams in Wyoming - a freestone river running through roadless national forest and wilderness terrain with exceptional populations of native Snake River finespotted cutthroat trout. The river sees a fraction of the pressure of nearby fisheries and rewards anglers willing to make the drive with genuine wilderness dry-fly fishing in spectacular mountain country.
Check current Wyoming Game and Fish Department regulations before you go. The Greys River has special regulations including catch-and-release requirements for cutthroat trout on portions of the river. Much of the drainage is accessible via the Greys River Road (Forest Road 10138) which follows the river for much of its length - a scenic and largely unpaved route through the Wyoming Range. Verify current regulations and road conditions before your trip.
Shop by type: dry flies, nymphs, Euro nymphs, hoppers and terrestrials, streamers.
The river
The Greys River flows approximately 75 miles from its headwaters in the Wyoming Range to its confluence with the Snake River at Palisades Reservoir. The upper river above the Greys River Road is the most remote and least pressured water - excellent cutthroat fishing in a true backcountry setting accessible by foot or horseback. The middle river along the Greys River Road is the most accessible and most productive section for drive-up fishing, with good cutthroat populations in every riffle, pool, and undercut bank. The lower river near Palisades Reservoir widens and deepens with larger fish but less classic dry-fly character.
Snake River finespotted cutthroat are the primary species throughout - a subspecies of cutthroat trout native to the upper Snake River drainage, distinguished by their fine spotting pattern and aggressive surface feeding behavior. These are wild, unhatchery-influenced fish that rise freely to dry flies and rarely require the technical presentations demanded by tailwater trout. The Greys is a river where a well-presented elk hair caddis or parachute hopper will catch fish consistently throughout the season.
This is freestone wilderness fishing - flows vary with snowmelt and summer rain, the river can be high and off-color in May and early June, and conditions improve dramatically as summer progresses. The best fishing window runs from late June through September with peak dry-fly action in July and August. No guides, no drift boats, minimal crowds - just wild cutthroat trout in the Wyoming Range.
Year at a glance
| Month | Primary hatches | Also carry | Typical sizes |
|---|---|---|---|
| Jan | Midges (limited access) | Small nymphs | 20-24 |
| Feb | Midges (limited access) | Small nymphs | 20-24 |
| Mar | Midges, BWO | Small nymphs | 18-22 |
| Apr | BWO, midges | Early stonefly nymphs | BWO 16-20 |
| May | Runoff - nymphs and streamers | Stonefly nymphs | varies |
| Jun | Salmonfly, golden stone, caddis | PMD start, yellow sally | Salmonfly 2-6, golden 6-10 |
| Jul | Caddis, PMD, hoppers | Yellow sally, golden stone, ants | Caddis 14-16, hopper 8-12 |
| Aug | Hoppers, caddis, PMD | Ants, beetles, yellow sally | Hopper 8-12, caddis 14-16 |
| Sep | BWO, hoppers, caddis | Mahogany dun, ants | BWO 16-20, hopper 8-12 |
| Oct | BWO, midges | Streamers, mahogany dun | BWO 16-20, midge 20-24 |
| Nov | Midges, BWO | Small nymphs | 18-24 |
| Dec | Midges (limited access) | Small nymphs | 20-24 |
January - February
The Greys River Road can be snow-covered and impassable in winter - access to most of the river is limited by road conditions rather than fishing regulations. The lower river near Palisades Reservoir remains accessible and holds fish year-round. Midges are the primary food source in winter. For most anglers the Greys River is a late spring through fall destination - plan accordingly and check road conditions before attempting winter or early spring access.
- Midges - 20-24. Red zebra midge and small Euro nymphs in the slower pools near the lower river.
- Check road conditions before attempting access - the Greys River Road is not maintained for winter travel.
March - April
The river is accessible in the lower sections as the Greys River Road opens with improving conditions. BWO begin on overcast afternoons in April. Midges throughout. Snowmelt begins in earnest by late April and flows rise through the month. The pre-runoff window in late March and early April can offer excellent fishing on the lower and middle sections before high water arrives - worth the trip for early-season cutthroat on BWO and midges with no other anglers in the canyon.
- BWO - 18-22 on overcast afternoons. Parachute BWO when fish are rising.
- Midges throughout. Red zebra midge subsurface.
- Early stonefly nymphs subsurface as flows rise. Nymphs.
May
Peak runoff on the Greys River. Snowmelt from the Wyoming Range pushes flows to their highest and most turbid levels of the year - typically unfishable for dry-fly anglers through most of the month. Stonefly nymphs and streamers in the deeper pools near the lower river can produce fish when flows moderate. Most anglers skip May on the Greys and wait for the June clearing. Check current flows before making the drive.
- Stonefly nymphs - 6-10 in the deeper pools during moderate flows. Nymphs.
- Streamers in the deeper lower river pools when flows are high and turbid - streamers.
June
The salmonfly hatch is the opening event of the Greys River dry-fly season and one of the finest in western Wyoming. As flows drop and clear from late May into June, the giant stoneflies begin hatching and the cutthroat respond with abandon - large adults bring the biggest fish to the surface and the fishing can be extraordinary when the timing aligns. Golden stones and large caddis overlap with the salmonfly hatch. PMDs begin on the flatter sections by late June. This is the most exciting and most weather-dependent month on the Greys - worth building a trip around if timing works out.
- Salmonfly - 2-6. The signature early-season hatch. Large adult stonefly dries when the hatch is on - see dry flies.
- Golden stone - 6-10 in the faster riffles and pocket water.
- Caddis - 14-16. Elk hair caddis evenings as flows drop and clear.
- Yellow sally - 14-16 in the riffles on warm afternoons.
- Late June: first PMD - Pale Morning Dun on the flatter sections.
July
July is the heart of the Greys River season. Flows have dropped to ideal wading levels, the river is running clear, and the full hatch sequence is underway. Caddis evenings are outstanding. PMDs in the mornings on the flatter sections. Hoppers begin along the meadow banks and canyon margins by mid-month and the cutthroat respond eagerly. Golden stones linger in the faster water. Yellow sallies in the riffles. Ants and beetles midday. This is the Greys River at its best - wild cutthroat rising freely in beautiful Wyoming Range country with minimal angling pressure.
- Caddis - 14-16 evenings. Elk hair.
- PMD - 16-18 mornings on the flatter sections. Pale Morning Dun.
- Hoppers - 8-12. Hoppers and terrestrials along the meadow banks and canyon margins. Cutthroat respond aggressively.
- Yellow sally - 14-16 in the riffles.
- Golden stone - 6-10 in the faster pocket water.
August
Hopper season peaks in August and the Greys River is exceptional terrestrial water. The meadow sections of the middle river concentrate grasshoppers along the banks and the Snake River cutthroat are among the most willing hopper-eating trout in Wyoming. Fish hoppers tight to the grassy banks and undercut edges with confidence - these are not selective tailwater fish. Caddis evenings continue strong. PMDs linger on the cooler upper sections. Ants and beetles midday. August on the Greys is as good as Wyoming wilderness dry-fly fishing gets.
- Hoppers - 8-12. Hoppers and terrestrials along the grassy meadow banks. These cutthroat eat hoppers with enthusiasm.
- Caddis - 14-16 evenings. Elk hair.
- PMD - 16-18 on cooler upper sections. Pale Morning Dun.
- Ants and beetles midday from hoppers and terrestrials.
September
September is the finest month on the Greys River. Crowds are minimal after Labor Day, BWO return with the cooling temperatures, hoppers continue through mid-month, and the Wyoming Range turns gold. The combination of hopper mornings, BWO afternoons, and caddis evenings with no other anglers on the water is what the Greys River is all about. Mahogany duns add variety on overcast days. The upper river sections are at their most dramatic in September - worth the extra miles on the Greys River Road.
- Hoppers through mid-September. Hoppers and terrestrials.
- BWO - 16-20. Parachute BWO and CDC Baetis emerger on overcast afternoons.
- Mahogany dun - 14-16 on overcast afternoons.
- Caddis evenings. Elk hair.
October
BWO and midges as the season closes. Road access becomes variable as early snowstorms affect the Greys River Road - check conditions before making the drive. The lower river near Palisades remains accessible and produces good BWO fishing on overcast October days. Streamers for the larger fish as temperatures drop. October on the accessible lower sections is excellent uncrowded fishing for the angler willing to deal with fall Wyoming weather.
- BWO - 16-20. Parachute BWO on overcast afternoons.
- Mahogany dun - 14-16 on overcast days.
- Midges - 20-24 picking back up. Red zebra midge subsurface.
- Streamers in the deeper lower river pools - streamers.
November - December
The Greys River Road closes or becomes impassable in most years by November - access is limited to the lower river near Palisades. The Greys is a summer and fall fishery at its best. Plan visits for late June through September for the full hatch experience and reliable road access throughout the drainage.
- Midges on the lower accessible sections. Red zebra midge subsurface.
- BWO on overcast afternoons when accessible. Parachute BWO.
A western dry and nymph assortment covers the core season. Add a salmonfly pattern for June and a hopper box for July through September. The Greys River does not require technical presentations or fine tippets - these are willing wild cutthroat that respond to well-presented dry flies throughout the season. The reward is genuine Wyoming Range wilderness fishing with native Snake River cutthroat in some of the most beautiful mountain country in the West.