Big Thompson River & Rocky Mountain National Park

Mid-June has arrived in Estes Park, and we are now fully into runoff season across much of the area. Despite higher water, fishing remains productive for anglers who adjust their approach and focus on the right water types. The Big Thompson below Lake Estes continues to offer the most consistent fishing in the area, while sections inside Rocky Mountain National Park are seeing increasing flows from snowmelt and afternoon thunderstorms.

This time of year rewards anglers who fish early or late in the day, target softer water, and stay flexible as flows can change quickly throughout the afternoon.

Big Thompson River Conditions (Tailwater Below Lake Estes)

The Big Thompson below Lake Estes continues to fish well despite rising runoff conditions throughout Northern Colorado. Current flows are elevated but remain fishable, especially during morning hours before daily snowmelt peaks. Trout are holding heavily along seams, softer edges, and deeper buckets away from the strongest current.

Water clarity is generally best during the morning and can become slightly stained later in the afternoon depending on temperatures and runoff intensity. Caddis activity is increasing, with BWOs and stoneflies also becoming more active.

Key Water to Target:

  • Soft seams along heavier current
  • Pocket water behind rocks
  • Deep runs with moderate current
  • Bankside structure and slower edges
  • Tailouts during lower-light periods

Effective Flies and Techniques:

  • Pat’s Rubber Legs (#8–12)
  • CDC Pheasant Tails (#16–20)
  • Sparkle Wing RS2 (#18–22)
  • Rainbow Warriors (#16–20)
  • Zebra Midges (#18–22)
  • Green caddis patterns
  • Thin Mint and olive Wooly Buggers in deeper water

Nymphing remains the most consistent producer. High-stick nymphing and indicator rigs with extra weight are both working well depending on river section. Dry fly opportunities are improving during afternoon and evening caddis activity, especially on calmer stretches below Lake Estes.

Big Thompson Canyon

The canyon section is seeing stronger runoff influence and more variable conditions throughout the day. Fish are concentrated in softer holding water and are often feeding aggressively when presentations reach the proper depth.

EXPECT:

  • Higher and faster water than earlier spring conditions
  • Productive pocket water throughout the canyon
  • Fish stacked along slower current breaks
  • Better conditions during morning hours

The canyon has been fishing best with larger attractor nymphs, stonefly patterns, and streamers during stained water periods. Adjusting split shot frequently is critical right now.

Rocky Mountain National Park Conditions

Runoff is now fully impacting many streams inside Rocky Mountain National Park. Moraine Park and lower meadow sections of the Big Thompson remain the most consistent moving water options inside the park, while many steeper creeks and higher elevation streams are still running cold and fast.

Midday fishing windows continue to improve as water temperatures rise slightly throughout the day.
Current conditions include:

  • Cold mornings with slower fish activity
  • Increasing afternoon runoff
  • Best fishing in meadow sections and softer channels
  • Technical presentations in clear slower water
  • Best Approaches in RMNP
  • Smaller natural nymph patterns
  • 5X–6X tippet
  • Focus on undercut banks and softer inside bends
  • Fish later morning through evening
  • Hopper-dropper setups beginning to produce during warmer afternoonsMid June Strategy – The biggest key right now is fishing softer water than you think you should.
    Successful anglers are:

    Fishing early before runoff peaks
    Using heavier flies and more weight
    Slowing presentations down dramatically
    Focusing on depth and drift quality
    Targeting softer current edges rather than main channels

    As runoff continues, trout will increasingly stack into predictable feeding lanes near slower current.

    Seasonal Outlook – Over the next several weeks anglers can expect:

    Continued runoff fluctuations
    Stronger caddis activity
    Improving evening dry fly opportunities
    Better streamer fishing during stained water periods
    Increasing hopper activity later in the month

    Once flows begin stabilizing, expect some of the best fishing of the summer to follow shortly after.

    Guided Fly Fishing in Estes Park

    Mid-June can be one of the most productive times to fish Estes Park if anglers understand how runoff changes trout behavior. Guided trips continue to produce quality fish daily on both the Big Thompson River and within Rocky Mountain National Park.

    Trips include all equipment, instruction, and customized locations based on current conditions and angler experience.

    Available trip lengths range from 2 to 10 hours.

CONCLUSION

Runoff season is here, but the fishing remains very good for anglers willing to adapt. Focus on softer water, fish with confidence, and don’t be afraid to fish bigger flies and heavier rigs than normal.

Conditions are changing daily, but opportunities remain excellent throughout Estes Park and Rocky Mountain National Park for anglers who stay flexible and fish smart. Best time canyon and tailwater, mornings and late afternoon into evening, getting hot 1pm-4pm. Best section Top 4 miles of the Big thompson Canyon