Hatch-chart pattern list

Best Flies for Colorado River (Grand County) (Colorado)

The Colorado River (Grand County) in Colorado fishes as both a wade and a float. It is a freestone fishery for Rainbow Trout and Brown Trout, with the most reliable window in April, May, June. The patterns below are matched to the hatch chart we publish for this water. They are not a live report of what other anglers caught this week.

This is not a live report of other anglers' catches. Presence and flow live on the Colorado River (Grand County) river page and the Colorado destination guide.

What's hatching now

Month, insect, size, and pattern from the Colorado River (Grand County) hatch chart. August is highlighted when that month exists in the chart. We do not invent a hatch that is not on the chart.

MonthInsectSizePattern
MarchBlue-winged Olive#18-22Parachute BWO
AprilBlue-winged Olive#18-22RS2
Midge#22-26Mercury Midge
MayCaddis#14-16Elk Hair Caddis
Golden Stonefly#10-12Stimulator
JunePMD#16-18PMD Sparkle Dun
Caddis#14-16X-Caddis
JulyPMD#16-18Pale Evening Dun
Trico#20-24Trico Spinner
OctoberBlue-winged Olive#20-22Parachute BWO
Midge#22-26Zebra Midge

Nymphs

Subsurface patterns matched to this river's chart and catalog. Fish them at the size the chart lists, not the size that looks good in the bin.

Dries

Dries and terrestrials for the Colorado River (Grand County). If the chart says a size 18 PMD, do not start with a 12.

Streamers

Streamers and wets for stained water, banks, and low light. This is not a claim that streamers are "on" today.

No catalog patterns in this group yet. Use the hatch chart and the river guide.

Setup

4X and 5X cover most nymphing. 4X on dries until the fish get picky, then 5X. A 3.0–3.8mm tungsten on the point and a lighter dropper is a default until you see the water. Tight-line the near bank and the heads of pockets. Use an indicator only when you need to search water you cannot euro.

FAQ

What flies work on the Colorado River (Grand County)?
Start with BWO Sparkle Dun and BWO Parachute, then match size to the hatch chart for the month you are standing in. The Colorado River (Grand County) does not need a 40-pattern box. It needs the right size on the insect that is actually in the drift.
When is the best time to fly fish the Colorado River (Grand County)?
The editorial window we list is April, May, June, September, October, November. That is a planning month range, not a guarantee. Shoulder months can fish well if flows and water temperature cooperate.
Do I need a guide on the Colorado River (Grand County)?
Colorado has walk-up wade water and, on some sections, float water. A guide is worth it for a first float or a technical tailwater. A hatch chart and a gauge are enough for a first wade if you already nymph. We list local guides and shops on this page when we have them.
Where can I see live flow for the Colorado River (Grand County)?
Open the Colorado River (Grand County) river page for the USGS gauge, access notes, and the same hatch chart this fly list is built from. We do not publish other people's spots or fish counts.
Is this a report of what's working now on the Colorado River (Grand County)?
No. Executive Angler does not publish other anglers' catches, GPS, or a crowdsourced hot fly. This page is hatch-chart patterns plus catalog flies. Presence on the river page is gauge and weather only.

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