Merced River
Yosemite Valley · El Portal · Merced Gorge
E California, USA
Open live forecast →Target species: Rainbow.
Stream gauge: 11264500. Flow and water temperature update on every refresh.
Weekly AI Outlook as of 06/05/26
The Merced is running high at 880 cfs but starting to drop from peak runoff, with water temps at 53.4°F — still a bit cold for reliable caddis emergence but getting close. Recent shop reports from Sierra Bright Dot confirm trout are feeding on caddis patterns as bugs start showing up with warming temps. Focus on nymphing deep pockets and slower edges until water drops another 200-300 cfs for comfortable wading.
- Flow: 880 cfs — dropping from peak but still pushy. Wade carefully, fish the soft water along banks and below boulders.
- Hatches: Caddis starting to emerge sporadically. Water temp needs 1-2°F more for consistent activity. Elk Hair Caddis #14-16 ready.
- Water Temp: 53.4°F — approaching the 55°F threshold where caddis emergence kicks into gear. Almost there.
- Best Window: Early morning before park crowds and heat. Focus on deep nymphing until hatches become more predictable.
Generated weekly from live USGS gauge readings, weather forecasts, and recent fly shop reports. Updates Friday mornings.
About this Water
- Freestone
- Best months: May–Oct, peak July–Sept
The Merced River drains the heart of Yosemite National Park, running west through dramatic granite canyon country to the San Joaquin Valley. The Yosemite reaches above El Portal hold native rainbow trout and brown trout in classic high-Sierra pocket water. The lower Merced below the park boundary offers more accessible wade and float fishing for browns and rainbows. Hatch activity centers on caddis, golden stones, and yellow sallies through summer; tippet management is critical given the often gin-clear water.
The Merced through Yosemite Valley offers fly fishing in front of Half Dome — one of the most photographed natural settings on Earth provides the backdrop for genuinely productive trout water.
January Outlook
January on the Merced River in Yosemite Valley is full winter. Yosemite National Park is open but with limited services. The river holds wild rainbow trout in the clear, cold water below El Capitan and Half Dome.
Productive Patterns
- Midge Pupa
- Hare's Ear
- RS2
- Soft Hackle
Tips
January on the Merced in Yosemite is a spectacular experience — the valley under snow with towering granite walls and clear trout water. The wild rainbows require careful presentation. A California sport fishing license plus NPS regulations apply.
Water Notes
Water 40–48°F. Clear Sierra winter conditions. Park access limited but open. Fewer visitors in January.
February Outlook
February on the Merced in Yosemite is late winter with occasional early Baetis hatches. The towering walls of Yosemite Valley at peak winter beauty provide an extraordinary backdrop.
Productive Patterns
- Baetis Nymph
- Midge Pupa
- RS2
- Hare's Ear
Tips
February is the quietest month in Yosemite with the fewest visitors. The Merced's wild rainbows are there year-round. Fish the long pools and glides below El Capitan and the Valley floor sections.
Water Notes
Water 42–50°F. Cold and clear. Winter road conditions — check NPS for any closures.
March Outlook
March on the Merced in Yosemite begins spring with early Baetis hatches and snowmelt starting. The waterfalls are at their most dramatic. Pre-runoff conditions can offer excellent fishing.
Productive Patterns
- Baetis Dry
- Midge Cluster
- Hare's Ear
- Elk Hair Caddis
Tips
March is a prime early-season window on the Merced before the spring runoff peaks in May. Yosemite Falls begins running. Wild rainbows are feeding actively after winter. The valley has more visitors in March than January but is still manageable.
Water Notes
Water 46–56°F. Pre-runoff conditions. Clear water. Waterfalls beginning. Fish the valley floor pools.
April Outlook
April on the Merced is excellent early April before snowmelt peaks. PMD and Caddis begin to emerge. Yosemite Valley fills with visitors and wildflowers. Peak waterfalls.
Productive Patterns
- PMD Nymph
- Elk Hair Caddis
- Baetis Dry
- Soft Hackle
Tips
Fish early April before snowmelt peaks. The Merced can rise rapidly in late April. Fish the valley floor sections between Yosemite Village and El Capitan Meadow. The wild rainbows are eager in the spring.
Water Notes
Water 50–60°F early April. Flows increasing from snowmelt in late April. Monitor USGS 11266500. Park is busy in April.
May Outlook
May brings high water to the Merced as Sierra snowmelt peaks. The river runs fast and high — often unfishable at peak runoff. Yosemite's waterfalls are at maximum flow.
Productive Patterns
- Large Stonefly Nymph
- Sculpin Streamer
- Rubber Legs
Tips
May is typically high water on the Merced. The peak runoff can make the valley sections very difficult to fish. If runoff is moderate, fish the slower side channels and eddies. Wait for flows to drop below 800 cfs for comfortable wading.
Water Notes
High runoff typically 800–3000 cfs in May. Glacial tint possible. Monitor flows before visiting.
June Outlook
June on the Merced sees flows receding from peak runoff. By late June the river typically reaches wadable levels. Caddis and PMD hatches begin as the water clears.
Productive Patterns
- Elk Hair Caddis
- PMD Dry
- Stimulator
- Rubber Legs
Tips
Late June can be excellent if the runoff has subsided — check USGS 11266500 for current flows. The valley is beautiful and busy in June. Early morning fishing before park visitors fill the meadows is most productive.
Water Notes
Flows dropping from May peak. Water clearing by late June. Water 56–64°F. Park is very busy in summer.
July Outlook
July on the Merced in Yosemite is summer with PMD, Caddis, and terrestrial activity. The park is at peak visitor capacity. Early morning fishing is essential.
Productive Patterns
- PMD Dry
- Elk Hair Caddis
- Hopper
- Stimulator
Tips
July is peak season in Yosemite — arrive by 6 AM to fish before the park fills. The Merced valley sections see heavy non-angling foot traffic. The wild rainbows are wary of overhead shadows in July. Lightweight tackle and careful approach are essential.
Water Notes
Water 60–68°F. Flows receded. Clear and wadable. Yosemite Valley is extremely busy — fish early.
August Outlook
August on the Merced is summer terrestrial fishing at its best. Hoppers, ants, and beetles produce the most surface takes. The park is still busy but evenings are excellent.
Productive Patterns
- Hopper
- Ant
- Beetle
- Evening Caddis
Tips
August evenings on the Merced after visitors leave the valley floor can be exceptional. Hopper-dropper rigs work well in the meadow sections. The wild rainbows of the Merced are beautiful fish in a beautiful setting.
Water Notes
Water 62–70°F. Low, clear summer flows. Evenings best. Park visitors everywhere during day.
September Outlook
September on the Merced is one of the best months — park crowds begin to thin, temperatures moderate, and Baetis hatches return. Wild rainbow trout are actively feeding.
Productive Patterns
- Baetis Dry
- Elk Hair Caddis
- Hopper
- Soft Hackle
Tips
September is a sweet spot on the Merced — the crowds thin after Labor Day, temperatures are perfect, and the fishing improves dramatically. The valley's granite walls take on warm afternoon light. One of the year's best months.
Water Notes
Water 56–64°F. Low, clear water. Flows stable. Yosemite in September is spectacular.
October Outlook
October on the Merced River is fall fly fishing in Yosemite Valley. Baetis hatches are excellent, the valley oak leaves are turning gold, and the crowds have departed. Some of the finest fishing of the year.
Productive Patterns
- BWO Parachute
- Hare's Ear
- Soft Hackle
- Elk Hair Caddis
Tips
October in Yosemite Valley is extraordinary — the fall colors, the solitude relative to summer, and excellent Baetis hatches make this perhaps the finest month of the year on the Merced.
Water Notes
Water 50–58°F. Excellent clarity. Fall conditions. Valley is quiet compared to summer. Permits not required in October.
November Outlook
November on the Merced in Yosemite is late fall. Baetis and midge hatches continue on warmer afternoons. The valley is very quiet with exceptional solitude.
Productive Patterns
- Zebra Midge
- BWO Nymph
- RS2
- Hare's Ear
Tips
November on the Merced is a true off-season gem. The valley has almost no visitors, the waterfalls begin to slow, and the wild rainbows are active in the cold clear water. Check NPS for road conditions.
Water Notes
Water 44–52°F. Late fall clarity excellent. NPS road conditions may affect access. Minimal visitors.
December Outlook
December on the Merced River in Yosemite is winter with possible snow and limited access. The river holds beautiful wild rainbows that can be caught on midges and small nymphs.
Productive Patterns
- Zebra Midge
- Midge Pupa
- RS2
- Soft Hackle
Tips
December fishing in Yosemite is for the adventurous — the valley may have snow and the park services are minimal. But the wild rainbows are there and the granite valley in winter is an unforgettable setting. Check road conditions before driving.
Water Notes
Water 40–48°F. Possible snow and ice. Check NPS road conditions. Minimal services. Year-round NPS regulations apply.
Hatch Calendar
| Insect | Peak | Active | Size | Productive Patterns |
|---|---|---|---|---|
| Caddis (Mother's Day / October) Brachycentrus spp. / Hydropsyche spp. |
May, Sep | Apr, May, Jun, Aug, Sep, Oct | #14–18 |
|
| Blue Winged Olive Baetis tricaudatus |
Apr, Oct | Mar, Apr, Sep, Oct, Nov | #18–20 |
|
| Hopper / Terrestrials Melanoplus spp. / Formicidae |
Jul, Aug | Jul, Aug, Sep | #8–14 |
|
Access & Approach
Yosemite Valley and El Portal are the main park bases. California fishing license required (national park entry separate). Wade access throughout the canyon; float water exists below the park boundary.
Nearby Fly Shops
- Sierra Bright Dot
- Sierra Trout Magnet
- Golden Trout Guiding Co
Regulations & License
Fishing in California requires a current license. Always verify season dates, bag limits, and any special-regulation waters before you fish.
California fishing regulations & license →
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About Current
Merced River conditions on Current combine real-time flow data (USGS, WSC, CDEC, CEHQ), weather, tide predictions, hatch probabilities calibrated to this specific water, and recent fly shop reports from the area.
Merced River is one of 245 hand-curated waters in Current. The app and web forecast also generate AI outlooks for any unlisted river, lake, or saltwater flat anywhere in the world — drop a pin or paste a name and Current produces a fresh seasonal outlook with weather, flow context, and recommended techniques.
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