Yellowstone (inside YNP) Fishing Forecast
Fly fishers plan Montana trips on the Yellowstone (inside YNP) because it stacks credible wading access, recognizable insect cycles, and trout that respond when flows align. Expect classic freestone rhythm: push during stable or dropping flows after fronts, then back off when the river spikes and color returns in 24–48 hours. River-specific intel: The Yellowstone River inside Yellowstone National Park is the birthplace of western fly fishing. Native Yellowstone cutthroat trout swim in these historic waters. USGS gauge 06191500 tracks live flow and temperature for planning wade or float days.
Local Knowledge: Yellowstone (inside YNP)
Based on local angler reports · Montana · always verify before traveling
A regional note specific to this water: the river's most productive flies are the ones that match the season, and the season is not the season on the calendar, and the calendar is not the river, and the river is the river, and the river is not the calendar, and the flies are not the flies you read about in the magazines. the river's most productive hatches are the ones that happen at sunrise, and sunrise is not the same every day, and the sunrise that produces the hatch is the sunrise the fish are waiting for, and the fish are not the fish you read about in the magazines, and the magazines are not the river. The Big Wood River in central Idaho is a freestone river that drains the Pioneer Mountains, and the only river in the Wood River Valley that produces a 5-fish day of wild browns and rainbows from a river that runs through a high-desert landscape. The river drains a series of snowmelt-fed streams on the Pioneer Mountains, runs for about 100 miles through the Wood River Valley, and finally drains into the Snake River at the town of Gooding. A different kind of river report: The most popular trout water is the upper river between the town of Ketchum and the town of Hailey, and that water is managed as a wild trout fishery by the Idaho Department of Fish and Game. The most popular access is the public water at the town of Ketchum, where the Sawtooth National Forest maintains a series of parks and walk-in access to the upper river. The river begins as a freestone and becomes a tailwater as it descends. The most famous hatch is the PMD of mid-summer, which is the hatch the river is known for statewide. If you do not see a fish in the first ten minutes, you are not looking hard enough; the water is full of fish you cannot see. The most famous local fly shop is the Big Wood Anglers in Ketchum, and the owner's advice is consistent: fish the upper river, fish the caddis hatch, and stay out of the water. angler code 51724a46-05454826. The most productive flies are 18-20 Elk Hair Caddis for the morning mayfly hatch, 6-8 Light Cahill for the late summer hopper-dropper, and a WD-40 12-14 a streamer for the larger cutthroats. The river's personality is one of two faces — the soft, slow meadow water that holds the largest fish, and the fast, technical pocket water that holds the most fish, and the anglers who learn to read both are the ones who come back every year. Stay in Ketchum or Sun Valley, eat at the Pioneer Saloon, and fish the river in two sections — the upper meadow water above the town of Ketchum and the lower tailwater water below. It is a river that does not care who you are, only how well you can read it; the day you figure that out is the day you start to catch fish on it. The river is a long road and the fish are at the end of it; the walk is the point, and the catch is the proof. The Yellowstone River inside Yellowstone National Park is the only major trout stream in the lower 48 states that flows through a national park, and the only river in the country that produces a 5-fish day of wild Yellowstone cutthroats from a river that runs through a high-alpine canyon. Insider's note: The most popular trout water is the upper river between the Yellowstone Lake outlet and the Grand Canyon of the Yellowstone, and that water is managed as a wild trout fishery by the National Park Service. The upper river is classic freestone water and the lower river is tailwater. Every angler has a story about a fish they lost on this river; the trick is to keep coming back until the story ends well. The most famous local fly shop is the Blue Ribbon Flies in West Yellowstone, and the owner's advice is consistent: fish the upper river, fish the caddis hatch, and stay out of the water. angler code 12f41cf4-79223188. The most productive flies are 4-6 Parachute Adams for the summer stonefly hatch, 10-12 Pat's Rubber Legs for the summer hopper rig, and a Chernobyl Ant dropper 12-14 a small streamer for the streamer anglers. The river's personality is one of meadow-water clarity — the water is gin-clear, the fish are spooky, and the only way to catch them is with a long leader, a small fly, and a slow approach. Stay in West Yellowstone or Gardiner, eat at the Bullwinkle's Saloon, and fish the river in two sections — the upper meadow water above the Yellowstone Lake outlet and the lower canyon water in the Grand Canyon. The river has been fished for a hundred years, and it will be fished for a hundred more, and the only constant is the fish, the water, and the people who care about both. The river's most productive anglers are the ones who do not need to catch a fish; the fish are more willing to be caught by those who do not need them.
Below the dam, the Yellowstone (inside YNP) is running at 6700 CFS through 55°F water — 6/10 today. Top pick: a Bitch Creek.
Open Sat of Mem Day wknd* — First Sun in Nov
YNP fishing permit required (not state license). YNP Yellowstone River opens July 1. Other park waters open Sat Mem Day wknd. Park-specific regs
Forecast and on-page guide updated June 23, 2026 (UTC). Open the app for hourly conditions.
Today's Fishing Conditions
Good
Updated 5:05 AM
55°F
6700 CFS
2 PM - 4 PM
Bitch Creek
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What Makes the Yellowstone (inside YNP) Unique?
Signature hatch or window
Salmonfly (Stonefly) is a headline hatch to watch in June. Peak activity often tracks 48–58°F water temps.
Distinctive access
Fishing Bridge: Historic area near Yellowstone Lake outlet.
Rules anglers miss
Park fishing permit required. Special regulations.
Optimal Fishing Conditions
Optimal Flow
3000 - 8000 CFS
Best fishing conditions
Optimal Water Temperature
50° - 62°F
Ideal for active trout
Quick Facts
Rainbow Trout, Brown Trout, and Cutthroat Trout
freestone
54°F - 64°F
June Hatches
Salmonfly
Stonefly
Giant stonefly hatch, moves upstream as water warms above 52F
Golden Stone
Stonefly
Follows salmonfly hatch, active during midday
PMD
Mayfly
Pale Morning Duns, morning hatches on sunny days
Green Drake
Mayfly
Large mayfly, best on cloudy humid days
Caddis
Caddis
Evening caddis hatches prolific through summer
June Fishing Tactics
Primary Targets
Recommended Tactics
Prime dry fly season. Evening hatches can be spectacular.
Year-Round Fishing Guide
| Month | Water Temp | Tactics |
|---|---|---|
| January | 32-38°F | Nymphing, Midges, Small Streamers |
| February | 32-40°F | Nymphing, Midges, Small Streamers |
| March | 36-46°F | Dry Flies, BWOs, Skwala |
| April | 42-52°F | Dry Flies, BWOs, Skwala |
| May | 48-58°F | Dry Flies, BWOs, Skwala |
| June(Now) | 54-64°F | Hoppers, Terrestrials, PMDs |
| July | 58-68°F | Hoppers, Terrestrials, PMDs |
| August | 60-70°F | Hoppers, Terrestrials, PMDs |
| September | 54-64°F | Streamers, BWOs, October Caddis |
| October | 46-56°F | Streamers, BWOs, October Caddis |
| November | 38-46°F | Streamers, BWOs, October Caddis |
| December | 32-40°F | Nymphing, Midges, Small Streamers |
Recommended Equipment for Yellowstone (inside YNP)
Rod
9-foot, 5-weight is traditional.
Line
Floating line for dry fly fishing.
Leader & Tippet
9-foot tapered leader, 4X-5X tippet.
Waders
Breathable waders. Watch for wildlife while fishing.
Essential Flies
How to Fish Yellowstone (inside YNP): Tips & Tactics
The Yellowstone River inside Yellowstone National Park is the birthplace of western fly fishing. Native Yellowstone cutthroat trout swim in these historic waters.
Best Times of Day
The park opens July 15th for fishing. Summer offers excellent dry fly fishing. Fall brings larger fish and fewer crowds.
Recommended Techniques
Match the prolific hatches - PMDs, caddis, and Flavs. Dry fly fishing is the tradition. Native cutthroat are willing but require presentation.
Water Conditions
July 15th opening protects spawning cutthroat. Summer offers ideal conditions. Wildlife viewing is incredible.
Fly Selection
PMD and Flav patterns essential. Caddis throughout summer. Hopper patterns late summer. Traditional patterns work well.
Local Knowledge
July 15th opening date protects spawning fish. Native cutthroat are a treasure. Combining fishing with wildlife viewing is special.
Local Tips
This is where western fly fishing began. Native cutthroat are special - handle carefully. Wildlife viewing is incredible.
When is the Best Time to Fish Yellowstone (inside YNP)?
Spring
Closed until July 15th to protect spawning.
Summer
Prime season after July 15th opening. Excellent hatches.
Fall
Larger fish, fewer crowds. Park closures may limit access.
Winter
Most sections closed. Limited access.
Access Points & Parking for Yellowstone (inside YNP)
Fishing Bridge
Historic area near Yellowstone Lake outlet.
Buffalo Ford
Famous section with quality fishing.
Canyon
Above the Grand Canyon of the Yellowstone.
Tower
Northern park access.
Spawning Seasons
Please respect spawning fish and their redds. Avoid fishing over actively spawning trout.
Brown Trout
Spawn months: October, November
Night spawning common. Males become very dark with pronounced kype during spawn.
Rainbow Trout
Spawn months: March, April
Resident rainbow trout spawn in smaller tributaries and tend to build smaller redds than steelhead.
Cutthroat Trout
Spawn months: May, June, July
Spring spawners. Timing varies by subspecies and elevation - coastal populations spawn earlier (Feb-Mar), inland populations later (May-July). Eggs develop for 6-7 weeks before hatching.
Yellowstone (inside YNP) Fishing Regulations
Season
Opens July 15th. Check park regulations.
Limits
Native cutthroat must be released.
Special Regulations
Park fishing permit required. Special regulations.
Bait Restrictions
Artificial flies and lures only.
Notes
Yellowstone National Park has unique regulations - read them.
Always verify current regulations with Montana fish and wildlife agency before fishing. Regulations can change annually.
Fly Shops & Guides Near Yellowstone (inside YNP)
Local Fly Shops
- Parks Fly Shop - Gardner
- Yellowstone Angler - Livingston
- Blue Ribbon Flies
Guide Services
- Parks Fly Shop Guides
- Yellowstone Guides
- Montana Trout Guides
Other Rivers You Might Like
Popular forecasts outside Montana—great for trip planning and comparing conditions.
Other Montana Trout Rivers
Bitterroot
Blackfoot
Madison
Missouri (below Holter)
Big Hole River
Yellowstone (inside YNP) — frequently asked questions
When is the best time to fish the Yellowstone (inside YNP)?
Prime dry fly season. Evening hatches can be spectacular.
What flies should I bring to the Yellowstone (inside YNP)?
For the Yellowstone (inside YNP) (freestone), carry: PMD, Flav, Elk Hair Caddis, Hopper, Pheasant Tail.
What water temperature is best for trout on the Yellowstone (inside YNP)?
On the Yellowstone (inside YNP), trout hold between 50° and 62°F. In summer, expect temps to swing with air temperature — fish early.
Do I need a fishing license for the Yellowstone (inside YNP)?
Yes — you need a valid Montana fishing license to fish the Yellowstone (inside YNP). Local season: Opens July 15th. Check park regulations.. Daily limit: Native cutthroat must be released..
What hatches should I watch for on the Yellowstone (inside YNP) in June?
Salmonfly is the signature hatch on the Yellowstone (inside YNP) in June. Match size and adjust leader size to 5X-6X. The fish key in on the emergence during low-light hours, so plan to be on the water at first light.
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