Troutline

Greys River

Wyoming·Star Valley·43.05° N, 110.82° W
Flow
425 CFS
Greys River above Reservoir, near Alpine
Water Temp
—
Condition
Well Below Normal
Weather
63°F
Slight Chance Showers And Thunderstorms
near Nordic

Insights

Flow
Low flows at 425 CFS
Fish are spooky. Lighten tippet and lengthen leaders.
Snowpack
Snowpack snowpack update
Snowpack data for Greys River basin is limited right now.

The Greys is a 50-plus-mile freestone that drops out of the Wyoming Range and meets the Snake River at Alpine, and it's about as close as Wyoming gets to a genuinely wild cutthroat river you can drive to. More than 95% of the trout here are native Snake River fine-spotted cutthroat — the strain with the pepper-fine spotting concentrated toward the tail — and they eat dry flies with the enthusiasm of fish that don't see much pressure. Browns, rainbows, a few cuttbow hybrids, brook trout in the colder upper tributaries, and mountain whitefish round out the mix, but the cutthroat are the point. Fish run 8 to 16 inches on average, which is honest freestone size; the reward here isn't trophies, it's solitude and a fish that comes up for a size 12 Stimulator without much fuss.

The whole river parallels one gravel road — Greys River Road (Forest Service Road 10138) — which leaves Highway 89 just south of the Snake River bridge at Alpine and runs to the headwaters at the Tri-Basin Divide. Access is genuinely easy: pull over almost anywhere past the Forest boundary and you're on fishable water. It's a wading river, not a float — fast pocket water, long glassy runs, deep cutbanks, and willow-lined meadow meanders. Best flows for wading are roughly 200–600 CFS. The Greys blows out hard during spring runoff (it can push well over 2,000 CFS in late May and June, running high and off-color), so the season is essentially late June through October once snowmelt drops out. Attractor dries and hopper-dropper rigs carry most of the summer; fall is when you throw streamers at the bigger browns in the lower canyon.

The trade-offs are real. Runoff timing is everything — show up in early June and you'll find brown water and no fishing. The road is long, dusty, and washboarded; the upper reaches are a commitment, with the Feathered Hook's private water starting 24 miles up at Deadman Creek. There's no drift-boat option, cell service disappears past Alpine, and while pressure is low by Jackson-area standards, the lower few miles near the Snake confluence do get worked. But if you want a cutthroat freestone where you can fish attractor dries in comparative solitude, the Greys delivers — and it stays underfished relative to the Snake and Salt next door.

Species

  • Snake River Fine-Spotted Cutthroat Trout
    Abundant · Jul-Oct · 8-16"

    More than 95% of the trout population and the defining fish of the river. Fine, pepper-like spotting concentrated toward the tail. Aggressive to attractor dries — Stimulators, Chubbys, and Royal Wulffs all move fish.

  • Brown Trout
    Common · Sep-Oct · 10-18"+

    Concentrated in the lower canyon near the Snake confluence, where the only real brown-trout size on the river lives. Best targeted with streamers during the fall pre-spawn.

  • Rainbow Trout
    Present · Jul-Sep · 8-14"

    A minority of the population; some rainbow-cutthroat hybrids ('cuttbows') show up mixed in with the cutthroat.

  • Brook Trout
    Present · Jul-Sep · 6-12"

    Cooler, higher stretches and the small upper tributaries. Eager and abundant in the headwater water toward the Tri-Basin Divide.

  • Mountain Whitefish
    Common · Year-round · 8-16"

    Native and common throughout; readily takes nymphs and makes a good winter and shoulder-season target when the trout are sluggish.

  • Colorado River Cutthroat Trout
    Localized · Jul-Sep · 6-12"

    Reported in some uppermost tributary and headwater water near the Tri-Basin Divide, where the Greys drainage brushes the Colorado River basin divide.

Ideal wading flow200–600 CFS
Blow-out>2,000 CFS
Ideal water temp50–62°F

July is prime — post-runoff, with stoneflies winding down into PMDs and caddis over classic dry-fly water. August and September are hopper and terrestrial season: low, clear water, eager cutthroat, and fall browns on streamers in the lower canyon. Late June can be excellent during the salmonfly and golden stone window if runoff has dropped, but timing varies year to year. October brings BWOs, streamers, and cooling water until snow closes the upper road. Spring through mid-June is runoff and generally not fishable on the mainstem. Watch gauge 13023000 near Alpine for the drop below roughly 700 CFS.

Sections

4 sections on this river

Lower Greys — The Canyon

WadeCutthroat · Brown Trout · Rainbow Trout · Whitefish

The lower few miles from the Snake confluence at Alpine up into the canyon — bigger, pushier water with deep cutbanks and runs, and some Class II–III whitewater between the Little Greys confluence and the highway bridge. The USGS gauge sits mid-reach near the bridge.

Best for: The only stretch of the Greys with legitimate brown trout size — streamers in fall for pre-spawn browns, with Snake River cutthroat and mountain whitefish throughout on attractor dries and nymphs.

Middle Greys — The Meadows

WadeCutthroat

Classic western freestone — willow-lined meadow meanders alternating with fast riffles and pocket pools, all clear, cold, and wadeable. This is the heart of the dry-fly water, roadside off Greys River Road with countless pullouts and dispersed campsites.

Best for: Snake River cutthroat on attractor dries and hopper-dropper rigs, with genuine sight-fishing in the flatter meadow sections. The quintessential walk-and-wade Greys experience.

Little Greys River (tributary)

WadeCutthroat · Brook Trout · Rainbow Trout

The one significant fishable tributary — it rises above Roosevelt Meadows in the northern Wyoming Range and runs about 15 miles to join the Greys just east of the highway bridge. Smaller, intimate freestone in its own drainage.

Best for: Cutthroat and brook trout on dries; a quieter small-stream alternative when the main Greys is high or crowded near Alpine.

Upper Greys — Headwaters

WadeCutthroat · Brook Trout · Rainbow Trout

Smaller, higher, colder pocket water and small meadow sections climbing toward the headwaters at the Tri-Basin Divide. A commitment — a long drive on gravel, with the Feathered Hook's private Deadman Ranch water beginning at the lower end.

Best for: Small-stream dry-fly fishing for eager, smaller cutthroat and brook trout, with Colorado River cutthroat reported in the uppermost tributary water. Solitude in a native-trout headwaters setting.

Regulations

Current fishing rules and restrictions

The Greys is in Wyoming Game & Fish Area 1 (Snake, Salt, Greys, Hoback drainages). A special artificial-flies-and-lures-only regulation applies from Corral Creek downstream to the Murphy Creek Bridge; general Area 1 stream rules apply elsewhere. Open year-round, though the practical season is late June through October.

  • Artificial flies and lures only from Corral Creek downstream to the Murphy Creek Bridge (Lincoln County)
  • General Area 1 creel limit: 3 trout daily; no more than 1 trout over 16"
  • No more than 1 cutthroat over 12" in the daily limit
  • Use or possession of live baitfish is prohibited throughout Area 1 (dead approved baitfish permitted)
  • Open to fishing year-round under general regulations
  • Wyoming resident or nonresident fishing license required; nonresident daily and annual options via WGFD

The Little Greys River carries no separate special regulation — general Area 1 stream rules apply. Confirm current-year rules against the Chapter 46 regulations before fishing, as creel limits and special-regulation reaches are revised periodically.

Source: Wyoming Game and Fish Department — Fishing Regulations (Chapter 46, Area 1). Regulations change annually — verify before fishing.

Access & Logistics

Getting there, fly shops, and lodging

Getting There

Alpine, WY

35–40 min south of Jackson via Hoback Junction; Jackson Hole Airport (JAC) ~45 min; Idaho Falls (IDA) ~1.5 hrs west.

Camping & Lodging

Extensive dispersed and developed Forest Service camping all along Greys River Road (FSR 10138) — the standard way to fish the middle and upper river, most dispersed sites free. Gas, lodging, and restaurants in Alpine at the river mouth; fuller services in Afton, about 35 minutes south in Star Valley.

No permits or reservations for general access — it's National Forest. Greys River Road is long gravel that can be rough and washboarded far up, and cell service ends past Alpine. The lower reach past the Forest boundary has the easiest roadside pull-offs. The Feathered Hook controls private membership water on the upper Greys at Deadman Ranch, beginning roughly 24 miles up where Deadman Creek joins.

Conditions data is live from public monitoring networks. Regulations change annually — always verify current rules with your state fish & wildlife agency before fishing.

More in Wyoming

View all 15 rivers

Star Valley

Salt RiverWY

Star Valley's home water — a spring-influenced freestone that runs north out of the Salt River Range through the ranch country around Afton, Thayne, and Etna into Palisades Reservoir. Wild Snake River fine-spotted cutthroat and brown trout in a float-first river most of Wyoming overlooks, with big pre-spawn browns running up out of the reservoir every fall.

Other regions

Buffalo Fork RiverWY

The wild, back-of-beyond cousin to the Snake it feeds — a small snowmelt freestone that gathers its North and South Forks deep in the Teton Wilderness and comes together in Buffalo Valley before joining the Snake near Moran. Almost pure Snake River fine-spotted cutthroat water, with mountain whitefish thick enough to rise during a stonefly emergence. The lower river along Buffalo Valley Road is an easy float-or-wade cutthroat float; the upper forks are a backcountry pack trip. No dam to steady it, so it fishes best on the drop from August into September.

Firehole RiverWY

The most unusual trout stream in the Lower 48 — a geyser-fed meadow river inside Yellowstone NP with vast White Miller caddis hatches, PMD and BWO windows, and a short fishing season (late May through early July, then September to early November) bracketing a summer that's too warm to fish.

Gibbon RiverWY

The Firehole's quieter sibling — the other geothermally-influenced headwater that joins it at Madison Junction to form the Madison. Technical spring-creek meadow flats above Gibbon Falls (the biggest fish) and forgiving canyon pocket water below, holding wild brown, rainbow, brook, native westslope cutthroat, and the odd Arctic grayling. A spring-and-fall fishery inside Yellowstone NP.

Gros Ventre RiverWY

The walk-and-wade counterpart to the crowded Snake River float scene in Jackson Hole — a medium freestone that drops out of the Gros Ventre Wilderness past the 1925 slide and its two slide lakes, then runs through the National Elk Refuge and Grand Teton National Park corridor to meet the Snake. Wild Snake River fine-spotted cutthroat eat attractor dries from July into fall once runoff drops; irrigation diversion pulls the lower river down hard by late summer.

Hoback RiverWY

The small roadside freestone you drive right past heading south out of Jackson — US-189/191 traces it the whole way down Hoback Canyon to the Snake at Hoback Junction. Wade-only water, mostly 15 feet wide, holding native Snake River fine-spotted cutthroat that charge attractor dries. Most fish run 8–13 inches, with bigger migratory Snake River cutthroat pushing up in late spring and early fall; the early-summer salmonfly and golden stone hatches are the marquee event once runoff drops in late June.

Lamar RiverWY

The marquee Yellowstone cutthroat river — a freestone rolling out of the Absaroka wilderness through the wide-open Lamar Valley, where pure Yellowstone cutthroat sip drakes and hoppers in glassy meadow runs. Sight-fishing on foot for 14-20"+ fish; comes into shape mid-to-late July and stays flash-prone all summer.