Yellowstone Park

 

YELLOWSTONE PARK

Report
JUL 30 — AUG 6, 2026
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Flow
3140CFS
Yellowstone River at Corwin Springs MT
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Water Temp
66.7°F
Updated 2026-07-30
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Weather
46–86°F
Areas Of Smoke
🎣
Reported By
Bruce Staples
On the water
The Yellowstone River at Corwin Springs is running 3,140 cfs at 66.7°F, with warming lake-outlet waters pushing fish back toward the lake and making early mornings the prime window. Afternoon thunderstorms are possible today under areas of smoke, with a sunny high near 84°F.
From the ShopMadison Losee · July 30, 2026

The entire Madison River drainage remains closed to fishing, excepting the Gibbon River above Norris Campground. Streams in the northeast corner of the park are rounding into shape but are becoming crowded with fly fishers. PMDs, yellow sallies, caddis, ants, and beetles are bringing fish up. Watch for afternoon thundershowers that can rain hard enough to discolor downstream waters.

The Gallatin and Gardner Rivers offer some great PM caddis activity with terrestrial insect populations building. The Yellowstone River below the lake is crowded with fly fishers and warming waters are beginning to switch fish back to the lake — best time to fish is early AM. Fishing in Fall River Basin streams is slowing because of summer heat; try long, drag-free drifts with grasshopper patterns.

Beula Lake is producing some of the fastest still-water fishing in the park, with cutthroat trout feeding on speckled dun, cinnamon caddis, and damselflies.

Hatch Chart
Insect Size Activity Prime Time
PMD (Pale Morning Dun) #16–20 Moderate — bringing fish up in northeast park streams Midmorning to early afternoon
Caddis #16–20 Strong — especially PM activity on Gallatin and Gardner Rivers Afternoon into evening
Yellow Sally (Little Yellow Stonefly) #14–16 Active — northeast corner streams Midday to afternoon
Ants & Beetles (Terrestrials) #14–18 Building — populations increasing across open-water drainages All day, peak midday heat
Grasshoppers #10–14 Emerging — key pattern for slowing Fall River Basin streams Late morning through afternoon
Cinnamon Caddis & Damselflies (Beula Lake) #14–18 Strong — cutthroats actively feeding at Beula Lake Morning and midday
Best Time Window
  • FIRST LIGHT TO 9 AM: Fish the Yellowstone River below the lake before warming water temperatures push cutthroats back toward the lake — crowds build fast, so arrive early.
  • MIDMORNING TO EARLY AFTERNOON: Target northeast corner streams for PMD, yellow sally, and terrestrial dry-fly action; watch for afternoon thunderstorms that can quickly discolor water downstream.
  • AFTERNOON INTO EVENING: Hit the Gallatin and Gardner Rivers for peak caddis activity; terrestrial patterns continue to produce throughout the warmest part of the day.
Guide's Tip
From the benchSpeckled dun, cinnamon caddis, and damselfly patterns are the ticket at Beula Lake — if you don't have catalog damsel patterns, pick up a simple Olive Woolly Bugger or soft hackle in #12–14 to cover the damselfly movement. Remember the entire Madison River drainage is closed; the Gibbon River above Norris Campground is the lone exception in that system. On the Yellowstone River below the lake, get on the water at first light before warming temperatures push fish back toward the lake.
Main Species

Yellowstone Cutthroat Trout

Brown Trout

Rainbow Trout
Report generated July 30, 2026 — Next update: August 6, 2026