Idaho ·
Snake River Fly Fishing Report - May 31, 2026
SNAKE RIVER
ReportMAY 31 — JUN 7, 2026
🌊
Flow
9040CFS
SNAKE RIVER AT MOOSE, WY
🌡️
Water Temp
48.4°F
Updated 2026-05-30
☀️
Weather
31–60°F
Rain Showers
💧
Clarity
Clear
Check post-storm
The Snake at Moose is running a blistering 9,040 CFS at 12.36 ft gauge height with water temps at 48.4°F — full peak runoff fueled by an early-melting 41%-of-median snowpack. The dam-to-Moose tailwater is ice-clear and fishing well; below Moose the river is off-color and wading is dangerous — float only.
What's Working — Hot Flies
Parachute - Blue Wing Olive #22
#22
Juju Baetis Tungsten #22
#22
Egan's Silver Bullet - Baetis #14
#14
Black Zebra Midge(TBH) #20
#20
Higa's SOS - Black #16
#16
Tungsten Pat's Rubber Legs - Tan & Brown #6
#6
Coffey's CH Sparkle Minnow Sculpin #6
#6
Olsen's Straggle Stone Brown Barbless #12
#12
Egan's GTI Caddis - Olive #12
#12
Corn-fed Caddis (CDC) Tan #20
#20
Egan's Thread Frenchie Jig - Olive #12
#12
Sculpzilla - Olive #4
#4
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Blue-Winged Olive (Baetis) | #18–22 | 🟢 Heavy — best dry-fly hatch on the river right now | 10 AM – 2 PM, especially on overcast/rainy days |
| Midges (Chironomidae) | #20–24 | 🟢 Active — consistent on the upper tailwater | Morning & evening; all day on cold/cloudy days |
| Early Caddis (Brachycentrus) | #14–16 | 🟡 Sporadic — beginning to appear in afternoon | 2 PM – dusk |
| Salmonfly Nymphs (Pteronarcys) | #6–8 | 🟡 Nymphs migrating — adults not yet flying in numbers | All day; fish the soft seams and cut banks |
| Skwala Stonefly | #10–12 | 🔴 Closing window — last stragglers | Midday warmth on sunny banks |
| PMD (Pale Morning Dun) | #16–18 | 🔴 Not yet — watch for emergence post-runoff in June | Late morning, post-runoff only |
Best Time Window
- 10:00 AM – 2:00 PM — Peak BWO hatch window on the tailwater; overcast skies and rain today will extend this window; watch for subtle sipping rises in back eddies and slow seams
- 7:00 AM – 9:30 AM — Morning midge activity on the tailwater; cold overnight temps (36°F) will keep fish feeding low and slow; tight-line nymphing with Zebra Midge or Higa's SOS most effective
- 2:00 PM – Dusk — Early caddis begin trickling off; afternoon temps peak near 54°F before falling; best window for swinging a wet caddis or fishing a CDC emerger in the tailwater flats
Guide's Tip
From the benchWith 9,040 CFS pushing through Moose and today's rain keeping skies dark all day, your best move is to focus exclusively on the dam-to-Moose tailwater — it's ice-clear, safe to wade in the shallower margins, and the BWO and midge hatches will fire hard under these overcast conditions. Set up a tight-line nymph rig with a Juju Baetis or Frenchie Jig as your anchor and watch for subtle sipping rises between 10 AM and 2 PM to switch to a dry. If you're floating the lower river, stay in the boat, hug the soft water on the inside bends, and let a heavy Pat's Rubber Legs or Sculpzilla do the work — the fish are there, they're just not fighting the main current.
Main Species
Snake River Fine-Spotted Cutthroat Trout
Brown Trout
Rainbow Trout
