October brings golden aspens, crisp mornings, and trout feeding aggressively before winter. This post highlights why October is one of the most underrated months to fish the Estes Park area, focusing on changing conditions, insect activity, and the ideal waters to target.

1. Why October Is a Hidden Gem

• Fewer crowds in RMNP and the Big Thompson

• Cooler water means more active trout

• Stunning fall colors and elk rut season enhance the experience

2. Where to Fish

• Big Thompson River (Below Lake Estes): Reliable flows, clear water, predictable fish movement

• Moraine Park / Horseshoe Park: Meadow stretches with great sight-fishing before temperatures drop

• Select Alpine Lakes: Still open early in October, with trout cruising the shallows

3. Seasonal Trout Behavior

• Increased feeding ahead of winter

• Browns transitioning to pre-spawn patterns

• Higher activity during late-morning to afternoon warmups

4. October Fly Box

• BWOs (#18–22)

• Elk Hair Caddis (#14–18)

• Griffith’s Gnat (#20–24)

• Ants and beetles during warm afternoons

• Pheasant Tails, Frenchies, and WD-40s subsurface

5. Tips for Success

• Fish the warmest hours (10am–3pm)

• Wear layers — mornings can be cold

• Use longer leaders and lighter tippet as water gets clearer

• Take time for photos — the fall scenery is unbeatable

October is one of the most visually stunning and productive fishing months of the year.
Book your October fly-fishing trip with Fly Fish Estes Park and let our guides put you on active trout, beautiful water, and unmatched fall scenery.
Schedule your guided trip before the season winds down.