Colorado ·
Arkansas River Fly Fishing Report - August 9, 2026
ARKANSAS RIVER
ReportAUG 9 — 16, 2026
🌊
Flow
196CFS
ARKANSAS RIVER NEAR NATHROP, CO
🌡️
Water Temp
—
Updated 2026-08-08
☀️
Weather
53–92°F
Mostly Clear
💧
Clarity
Clear
Check post-storm
Flow at Nathrop is running 196 CFS at a gauge height of 3.38 ft — low, clear summer conditions that demand precise presentations and reward anglers who work the banks and seams early. Water temps are climbing into the afternoon, so morning and evening windows are your best bets before the heat sets in.
What's Working — Hot Flies
Bionic Hopper - Tan #12
#12
Bionic Hopper - Purple #12
#12
Bionic Ant 2.0 - Black #16
#16
Bionic Ant 2.0 - Brown #12
#12
Corn-fed Caddis (CDC) Tan #20
#20
Corn-fed Caddis (CDC) Olive #20
#20
Egan's GTI Caddis - Olive #12
#12
Tungsten Split Case Nymph - PMD #20
#20
Egan's Thread Frenchie Jig - Olive #12
#12
Roza's World Spain Perdigon Barbless #18 - 32
#18
Juju Baetis Tungsten #22
#22
Parachute - Blue Wing Olive #22
#22
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Grasshoppers / Terrestrials | 10-14 | Heavy | 10 AM - 5 PM |
| Caddis | 18-20 | Moderate | 6 AM - 10 AM |
| PMD (Pale Morning Dun) | 18-20 | Moderate | 9 AM - 12 PM |
| Blue Wing Olive (Baetis) | 20-22 | Light | 5 PM - 7 PM |
| Ants / Beetles | 14-18 | Moderate | 11 AM - 4 PM |
Best Time Window
- 6 AM - 10 AM: Early caddis and PMD activity in riffles and tailouts — best dry-fly window before heat builds.
- 10 AM - 4 PM: Prime hopper and terrestrial time along grassy cutbanks; nymph deep slots when surface action slows.
- 6 PM - Dark: Post-storm BWO and caddis evening rise in slower flats — watch for sipping fish in the film.
Guide's Tip
From the benchWith flows at 196 CFS and clear water, fish are spooky — stay low, approach from downstream, and keep your shadow off the water. The hopper bite is your best mid-day play: work the right bank where grassy meadow edges overhang the current, and land the fly within 6 inches of the bank. Keep a close eye on the sky after 5 PM — afternoon thunderstorms are possible and can blow up the bite fast, so plan to be off exposed water by 4:30 PM and return for the evening caddis and BWO window once storms clear.
Main Species
Brown Trout
Rainbow Trout
Mountain Whitefish
