South Fork cutthroat hunting the edges as Snake River peaks at June runoff

What's Biting

What's Next

Over the next two to three days, the 13,000 cfs reading will hold roughly steady or begin a modest decline depending on overnight temperatures at elevation. Warm days accelerate snowmelt and can push flows higher, while a cooler stretch can produce a noticeable drop within 24 to 48 hours. Check USGS gauge 13037500 daily and watch for any sustained downward trend, since even a 1,500 to 2,000 cfs reduction can meaningfully open up wadeable water and shift fish behavior across the South Fork.

Right now, streamers fished tight to the bank are the strongest play. High, slightly off-color water means fish are relying more on movement and silhouette than precise imitation. Larger weighted patterns, olive or tan bunny leeches and sculpin profiles, stripped slowly through the soft-water pockets just off the main current will intercept both cutthroat and brown trout holding in the breaks. Gink and Gasoline (fly) makes the point plainly in their nymphing coverage: adding more weight and fishing deeper drifts almost always outperforms finesse presentations when rivers are running fast and full. That principle applies directly to the Snake at current levels.

Dry fly opportunity is limited at peak runoff, but keep an eye on late afternoons. Caddis and early PMDs occasionally coax fish to the surface in calmer eddies even when the main stem is running hard. This transition window, a few rising fish showing while the river is still elevated, can deliver some of the year's most memorable dry fly moments if you are positioned correctly in a protected inside bend.

By mid-to-late June, expect flows to begin receding toward the South Fork's summer baseline. That drop typically triggers the South Fork's legendary PMD hatch, one of the most prolific in the Rockies, with top-tier dry fly fishing from mid-morning through afternoon. Start building your box now: Pale Morning Dun patterns, cripple emergers, and para-duns in sizes 16 through 18 are the priority before the river drops into prime shape.

Anglers planning a weekend trip should target early morning or evening sessions to find the softest water. At current levels, aggressive wading on the main stem is not advisable. Stick to established access points and prioritize bank fishing or float trips over in-river wading.

Context

Thirteen thousand cfs in early June on the Snake River near Heise is a significant but seasonally expected reading for this drainage. The Snake River basin draws snowpack from the Wyoming ranges, the Tetons, and the eastern Idaho highlands, and peak runoff typically arrives sometime between late May and mid-June depending on the winter's accumulation and spring temperatures. A 13,000 cfs reading falls in the elevated-but-float-fishable range; heavy snowpack years can push the mainstem well above 20,000 cfs at peak, while dry winters produce a notably earlier and lower crest.

The broader Snake River watershed is receiving attention this year on the 50th anniversary of the 1976 Teton Dam failure, which Hatch Magazine examines in depth as the debate over a potential dam rebuild resurfaces publicly. That catastrophic release reshaped the Snake River floodplain and stressed the fishery for years. The fact that the South Fork has since developed into one of the premier wild trout destinations in the American West reflects both the river's underlying productivity and sustained conservation investment over the decades that followed.

Trout Unlimited documents active habitat restoration work on tributaries supporting Snake River cutthroat populations, including Spread Creek in the adjacent Wyoming drainage. These projects reinforce the long-term health of the fine-spotted subspecies that defines the South Fork's identity as a fishery and its draw for visiting anglers each season.

From a seasonal standpoint, a June with healthy snowmelt runoff is a positive indicator for the fall fishery. Adequate cold water now translates to cooler summer temperatures later, reducing thermal stress on trout during August, historically the most challenging month for fish in the Snake system. Anglers frustrated by high water in early June can reasonably expect the back half of the season to benefit from the conditions they are working around today.