Top 5 Wyoming Rivers Fishing This Week | September 2026

The Gros Ventre River was flowing on the report date at 233 cfs (normal) with a stable trend. Water Temperature: 53°F (prime). Why This Week: Flow 233 cfs (normal). Water temperature 53F. This week’s forecast shows temperatures ranging from 47-65°F. Calm winds make indicator nymphing more effective.

Insect Activity: Late-September mornings and evenings on the Gros Ventre are bringing steady midge activity in the size 18-24 range, with fish keying on emergers just under the surface as water hovers in the low 50s. Low light at dawn and dusk is prime streamer water too — olive and black Woolly Buggers and Muddler Minnows in sizes 4-8 are pulling browns out of the deeper bends ahead of the fall spawn.

Where to Fish: With flows holding steady at 233 cfs, work the deeper runs and undercut banks for streamer swings first, then switch to the slower tailouts and back eddies for midges once the sun climbs. Clear, low fall water calls for a long leader and 6X tippet — sight-fish the softer inside seams where trout are holding out of the main current.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Buffalo Fork – Jackson Hole was flowing on the report date at 178 cfs (normal) with a falling trend. Water Temperature: 50°F (prime). Why This Week: Flow 178 cfs (normal). Water temperature 50F. This week’s forecast shows temperatures ranging from 46-64°F. Calm winds make indicator nymphing more effective.

Insect Activity: No specific hatch is dominating the Buffalo Fork this week, but with water sitting near 50°F and nights already dipping into the high 30s, terrestrials remain the reliable play — Parachute Ants and Amy’s Ants in sizes 12-16 are still drawing looks on sunny afternoons. Cooling water is also pushing browns and cutthroat onto baitfish, so don’t leave the streamer box at home.

Where to Fish: At a wadable 178 cfs, the Buffalo Fork fishes bank to bank — target the riffle-to-pool transitions and log jams where terrestrials get pinned against structure. Swing a Woolly Bugger through the softer inside bends at midday, then tighten up to dries in the last hour of light when bug activity peaks.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Lamar River was flowing on the report date at 153 cfs (normal) with a falling trend. Water Temperature: 54°F (prime). Why This Week: Flow 153 cfs (normal). Water temperature 54F. This week’s forecast shows temperatures ranging from 50-68°F. Calm winds make indicator nymphing more effective.

Insect Activity: The Lamar’s hopper bite is fading but not done — Dave’s Hoppers and Chubby Chernobyls in sizes 10-12 along the grassy banks can still draw a take on the warmer afternoons. Early risers should also watch for a light Trico spinner fall in sizes 20-22 over the slower flats just after sunrise before the day warms.

Where to Fish: At 153 cfs, the Lamar’s braided channels stay easy to read — start with nymphs through the deep cutbanks and current seams below Tower Falls, then work the grassy edges with hoppers as temperatures climb into the high 60s. Cloud cover through midday should keep fish looking up longer than usual, so hold off switching back to subsurface too early.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Firehole River was flowing on the report date at 190 cfs (normal) with a stable trend. Water Temperature: 63°F (warm). Why This Week: Flow 190 cfs (normal). Warm but fishable water at 63F. This week’s forecast shows temperatures ranging from 43-61°F. Calm winds make indicator nymphing more effective.

Insect Activity: The Firehole’s geothermal warmth keeps this stretch fishing differently than the rest of the park — with water near 63°F this week, caddis and small mayflies like Parachute BWOs and Sparkle Duns in sizes 18-20 are still active later into the fall than nearby freestones allow. Plan around the warmest afternoon hours for the best dry-fly window before overnight lows in the low 30s shut activity down.

Where to Fish:Because this water runs warmer than typical for the season, fish late morning through early afternoon rather than dawn, and handle any released fish quickly.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The North Platte River was flowing on the report date at 535 cfs (normal) with a stable trend. Why This Week: Flow 535 cfs (normal). No water temperature reading. This week’s forecast shows temperatures ranging from 54-72°F. Calm winds make indicator nymphing more effective.

Insect Activity: No water-temperature telemetry is reporting on the Miracle Mile gage this week, but this tailwater’s scud and sowbug base never really goes out of season — size 16-18 Sow Bugs and Scuds fished deep and slow remain the bread-and-butter subsurface bite below the dam. A size 20-22 Zebra Midge or Mercury Midge dropper is also worth adding in the flatter, clearer runs.

Where to Fish: Flow is holding at a steady 535 cfs, well within this tailwater’s typical range, so focus nymph rigs on the deeper slots and current breaks where scuds get flushed from the weed beds. Afternoon wind out of the southwest can gust to 25 mph, so plan an early start and tuck into bank-side pockets for shelter once it picks up.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.