Big Thompson Canyon: Lake Estes to Drake / Loveland
Big Thompson Canyon — Fishing Report for April 27, 2026
Quick Stats
Flow: 25 CFS | Trend: Falling | Fishability: Fair | Weather: Snow showers likely, high 42°F
The Bite
April on the Big Thompson is usually one of the Front Range's better dry fly windows, but this week is asking anglers to earn it. Water temps are sitting at 38°F — well below the 42–50°F range typical for late April — and snow showers are in the forecast through at least Wednesday. With a historically dry water year in the basin (snowpack at a fraction of normal and overall precipitation running about a third below average), the river is flowing low and cold rather than building toward the seasonal peak. That's not all bad news: flows at 25 CFS and falling are clear, accessible, and well within the fishable band. The fish are here. They're just not in a hurry.
At 38°F, trout metabolism slows considerably. Don't expect aggressive surface takes or wide feeding lanes — fish will be holding tight to structure, conserving energy in the slower water behind boulders and in the deeper slots of plunge pool eddies. Your best window today is likely a narrow one: if cloud cover softens and temperatures nudge toward the mid-40s between noon and 3 PM, a sparse BWO hatch is possible. Don't count on it being heavy given the cold, but the canyon's sheltered character gives it a better shot than open water. Morning midges are worth a look in the slower tailouts before the snow picks up.
The ongoing snow is worth watching not just for comfort but for its effect on the water. Snowmelt from today's storm could bump flows slightly by Tuesday or Wednesday — nothing dramatic given the light snowpack, but worth checking the gauge before you head out.
What to Fish
- RS2 #20–22 — Dead-drift through plunge pool eddies and slower pocket water seams. This is your workhorse today.
- Pheasant Tail Nymph #16–18 — Weighted, on point in a double-nymph rig. Let it tick bottom through the deeper slots.
- Black Stonefly Nymph #14–16 — Nymphs are active in the riffles; a good anchor fly for a two-nymph setup.
- Griffith's Gnat #18 — If midges are showing in the morning, a natural drift through the slower tailouts can produce.
- Parachute BWO #18–20 — Keep one tied on and ready. If the hatch fires between noon and 3 PM, switch quickly.
- Sparkle Wing RS2 #20 — Emerger option if fish are sipping just below the surface during any BWO activity.
Tactics & Rigging
Given the cold water and low flows, go deep and slow. Rig a Black Stonefly Nymph #14–16 as your anchor on point, with an RS2 #20 trailing 14–16 inches behind on 6X fluorocarbon. Add enough split shot to keep the rig ticking bottom — in 25 CFS, you won't need much. Focus your drifts on the deeper pockets directly behind mid-channel boulders and the slower water at the tail of plunge pools, where lethargic fish will stack up rather than holding in the faster current. Short, accurate casts are the rule in this canyon; the steep gradient means lies are tight and drag sets in fast.
If a BWO hatch develops, drop down to a single Parachute BWO #18–20 on 6X or a dry-dropper with a Sparkle Wing RS2 #20 hung 14 inches below. Watch for subtle sips in the slower eddies rather than splashy rises — cold-water takes are easy to miss.
Access & Logistics
Highway 34 through the canyon provides roadside access to most of the fishable water. The upper catch-and-release section from Olympus Dam to Waltonia Bridge is the priority water — artificial flies and lures only in that stretch. With snow in the forecast, check road conditions before heading up; the canyon can get slick quickly. Dress in layers and plan for wet, cold hands. Verify current regulations with CPW before fishing.
Stop by Estes Angler or Kirk's Fly Shop for flies, local intel, and to support the shops that keep this fishery healthy.
Looking Ahead
Snow continues through Tuesday with another round possible Wednesday before partial clearing — water temps should stay suppressed into midweek, keeping conditions challenging but fishable. If the sun returns by Wednesday afternoon, expect the BWO hatch to strengthen and fish to become noticeably more active; that could be the best window of the week.