Montana ·
Stillwater River Fly Fishing Report - June 21, 2026

STILLWATER RIVER
ReportJUN 21 — 28, 2026
🌊
Flow
—CFS
🌡️
Water Temp
—
☀️
Weather
49–81°F
Chance Rain Showers
💧
Clarity
Clear
Check post-storm
Live gauge data is unavailable for the Stillwater today, but web intel from early June confirms flows were dropping and clearing after runoff, with visibility improving and trout moving back to fishable lies along the banks. With a warm, mostly sunny Sunday ahead (high near 81°F) and a storm system building Monday, today is your best window of the week.
What's Working — Hot Flies

Tungsten Split Case Nymph - PMD #20
#20

Stealth Link Mercer - PMD #20
#20

Parachute - Blue Wing Olive #22
#22

Juju Baetis Tungsten #22
#22

Top Secret Baetis #16
#16

Corn-fed Caddis (CDC) Tan #20
#20

Egan's GTI Caddis - Olive #12
#12

Olsen's Straggle Stone Brown Barbless #12 - 32
#12

Tungsten Pat's Rubber Legs - Tan & Brown #6
#6

Egan's Frenchie #12
#12

Bionic Hopper - Tan #12
#12

Bionic Ant 2.0 - Black #16
#16
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Pale Morning Dun (PMD) | #16-#20 | Heavy | 10 AM - 2 PM |
| Blue-Winged Olive (BWO) | #20-#22 | Moderate | 7 AM - 10 AM |
| Spotted Sedge Caddis | #14-#16 | Moderate | 5 PM - 8 PM |
| Midge | #20-#22 | Light | 7 AM - 9 AM |
| Stonefly (Golden) | #6-#10 | Light | 11 AM - 3 PM |
Best Time Window
- 6:30 AM - 9:30 AM: Early BWO and midge activity on flat tailouts; nymph or dry-dropper along shaded bank seams before the sun hits the water.
- 10 AM - 2 PM: Peak PMD hatch window; switch to PMD dries and emergers in the inside bends and slower runs as fish rise aggressively.
- 5 PM - 8 PM: Evening caddis and attractor window; fish hoppers and CDC caddis tight to grassy banks as temperatures cool and fish move shallow.
Guide's Tip
From the benchWith flows dropping and clearing post-runoff, trout are pushing back to their feeding lanes along the banks and in the inside seams of bends. Focus your morning on nymphing the 2-4 foot depth range tight to the bank with a tungsten anchor fly, keeping your drift as drag-free as possible. By mid-morning when PMDs start popping, switch to a dry or emerger and work the slower flat water just above riffles where fish will be sipping in the film. Get off the water by late afternoon if you can — Monday's storm system will likely blow things up, so today's sunny window is the one to capitalize on.
Main Species
Rainbow Trout
Brown Trout
Yellowstone Cutthroat Trout