Colorado ·
Colorado River Fly Fishing Report - September 20, 2026

COLORADO RIVER
ReportSEP 20 — 27, 2026
🌊
Flow
613CFS
ROARING FORK RIVER AT GLENWOOD SPRINGS, CO.
🌡️
Water Temp
56.5°F
Updated 2026-09-19
☀️
Weather
41–75°F
Slight Chance Rain Showers
💧
Clarity
Clear
Check post-storm
Flow is running at 613 CFS at the Roaring Fork/Glenwood gauge with water temps at a crisp 56.5°F — a significant jump from last week's 256 CFS, so expect slightly off-color water in lower sections and concentrate on slower seams and eddies where trout are stacking up. Sunny skies and a high of 72°F today will warm things up nicely through midday, triggering both terrestrial activity and afternoon BWO hatches.
What's Working — Hot Flies

Parachute - Blue Wing Olive #22
#22

Juju Baetis Tungsten #22
#22

Top Secret Baetis #16
#16

Bionic Ant 2.0 - Black #16
#16

Bionic Ant 2.0 - Purple #16
#16

Bionic Hopper - Tan #12
#12

Egan's Thread Frenchie Jig - Olive #12
#12

Egan's Frenchie #12
#12

Black Zebra Midge(TBH) #20
#20

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

Egan's Silver Bullet - Baetis #14
#14

Olsen's Straggle Stone Brown Barbless #12 - 32
#12
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Blue-Winged Olive (Baetis) | 20-22 | Moderate | 11 AM - 2 PM |
| Caddis | 16-18 | Light | 4 PM - 6 PM |
| Terrestrials (Ants) | 16-18 | Moderate | 10 AM - 3 PM |
| Terrestrials (Hoppers) | 12 | Light | 12 PM - 4 PM |
| Midges | 20-22 | Moderate | 7 AM - 10 AM |
Best Time Window
- 7 AM - 9:30 AM: Pre-sun midge and nymph fishing in slow flats and eddies before the crowds arrive.
- 11 AM - 2 PM: Prime dry fly window as BWOs hatch and terrestrials become active along sunny, grassy banks.
- 4 PM - 6 PM: Evening caddis activity picks up — work the riffles and tailouts with a CDC caddis as light fades.
Guide's Tip
From the benchFlows are up to 613 CFS from last week's 256 CFS, so the river has more push than anglers have seen recently — focus your nymphing efforts on the inside seams of bends and the soft water directly behind mid-channel boulders where trout are conserving energy. Set your indicator depth at least 1.5x the water depth to get heavy jig nymphs into the strike zone quickly. For dry fly action, don't abandon the banks — terrestrial and BWO risers will be tucked tight to the grass and willows in the slower margin water, largely unaffected by the higher mid-channel flows. Time your dry fly session for the 11 AM to 2 PM window when warming air temps and sunny skies will push both ant and BWO activity to its peak.
Main Species
Brown Trout
Rainbow Trout
Colorado River Cutthroat Trout
