What flies are hatching on the Yellowstone River right now?

Current and seasonal hatches on the Yellowstone River include Caddis. Use the AI Hatch Advisor on this page for a live, temperature-aware recommendation.

What's the current flow on the Yellowstone River?

The Yellowstone River is running at 2,630 CFS at the At Corwin Springs gauge. Readings update every 15 minutes from the USGS Water Services API.

Is the Yellowstone River fishable today?

Yellowstone River is rated marginal right now. Flow is 2,630 CFS at the At Corwin Springs gauge. Go in prepared — heavier tippet, cautious wading, or target edges and seams.

Yellowstone River Fly Fishing Conditions

Live Conditions

Yellowstone River — At Corwin Springs

Marginal

2,630CFS

Discharge

1.34ft

Gauge Height

65.3°F

Water Temp

Updated 1 hr agoView on USGS ↗

7-Day Flow

→ Stable

RisingFallingStable

24-Hr Pressure

25.61 inHg · → High/stable

Falling (good)RisingHigh/stable

Voluntary Catch-and-Release Advisory

Water temperature is at or above 65°F. At these temperatures trout are physiologically stressed and have a higher post-release mortality rate. Consider waiting for cooler conditions — early morning or evening — or choosing a tailwater with regulated temperatures.

Local Weather

56°FClear sky

Wind 11 mph25.61 inHg Low & stable

Tough conditions — fish deep

Today

🌤️

Mainly clear

90° / 63°

Tomorrow

☁️

Overcast

71° / 53°

Tue

☀️

Clear sky

77° / 49°

Wed

☀️

Clear sky

87° / 52°

Cold front incoming — go deep with nymphs, surface activity likely slow.

Weather by Open-Meteo · No API key · Updated every 30 min

What should I fish today?

⚡ AI

AI-powered recommendation using today's live flow, temperature, and hatch data.

4

Time of Day

Using: 2,630 CFS · 65.3°F · PMDs continue. HOPPER SEASON peak

What should I pack?

Rod, flies, tippet, and safety gear specific to today's Yellowstone River conditions.

🪰 Hatch Calendar

Yellowstone River · August · Late Summer

Full calendar →

🟢 Active now at 65.3°F water

Caddis

🟡 Approaching — within 5°F of trigger range

Pale Morning Dun

Select month

JanDec

PMDs continue. HOPPER SEASON peak (size 8-12) — Paradise Valley grasshoppers hammer the banks. Caddis evenings. Hot afternoons — hoot-owl restrictions common on the lower Yellowstone. Fish dawn and dusk.

PMDCaddis

🟢 Active · 🟡 Approaching · ⚪ Seasonal only

River Map

Loading map…

USGS Gauge (click for site ID)Fishing Access / SectionScroll to zoom disabled — use map controls

About Yellowstone River

Longest free-flowing river in the lower 48 — undammed from Yellowstone Park through Paradise Valley to the plains. Wild Yellowstone Cutthroat, browns, and rainbows in classic riffle-pool freestone water.

SalmonflyGolden StoneCaddisPale Morning DunHopperBlue-Winged OliveMidge

Regulations

Standard Montana trout regulations apply on the Yellowstone; native Yellowstone Cutthroat are the species of concern, and catch-and-release is strongly encouraged for wild cutthroat. Montana fishing license required. Verify current regs at fwp.mt.gov before fishing.

Learn More

Guides to help you fish Yellowstone River with more confidence.