What flies are hatching on the San Joaquin River (Upper) right now?

Current and seasonal hatches on the San Joaquin River (Upper) include Salmonfly, Golden Stone, Pale Morning Dun. Use the AI Hatch Advisor on this page for a live, temperature-aware recommendation.

What's the current flow on the San Joaquin River (Upper)?

The San Joaquin River (Upper) is running at currently unavailable — check the USGS gauge at the primary station for the latest reading. Readings update every 15 minutes from the USGS Water Services API.

Is the San Joaquin River (Upper) fishable today?

Live conditions for San Joaquin River (Upper) are unavailable right now. Check the embedded gauge widget on this page for the latest data.

San Joaquin River (Upper) Fly Fishing Conditions

No Data

Gauge data unavailable for San Joaquin River (Upper).
Check USGS directly ↗

24-Hr Pressure

27.2 inHg · → High/stable

Falling (good)RisingHigh/stable

Local Weather

81°FClear sky

Wind 7 mph27.2 inHg Low & stable

Tough conditions — fish deep

Today

☀️

Clear sky

87° / 68°

Tomorrow

☁️

Overcast

85° / 68°

Tue

☁️

Overcast

75° / 55°

Wed

☁️

Overcast

77° / 51°

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.

Time of Day

Using: BWOs returning

What should I pack?

Rod, flies, tippet, and safety gear specific to today's San Joaquin River (Upper) conditions.

🪰 Hatch Calendar

San Joaquin River (Upper) · September · Early Fall

Full calendar →

Showing typical dates — water temperature data unavailable for live hatch predictions.

Select month

JanDec

BWOs returning (size 18-20). PMDs tapering. Cool mornings — short fall window before snow.

Blue-Winged OlivePMD

River Map

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

About San Joaquin River (Upper)

The upper San Joaquin River above Mammoth Pool Reservoir flows through a spectacular granite canyon in the Sierra Nevada. Wild rainbow and brown trout inhabit the cold, clear water, with upper wilderness sections offering remote backcountry fishing. The lower accessible sections near North Fork provide roadside access for day anglers.

SalmonflyGolden StonePale Morning DunCaddisBlue-Winged Olive

Regulations

Live CFS data unavailable — no road-accessible USGS gauge on the wilderness sections. General season regulations apply above Mammoth Pool. Wilderness sections may require a wilderness permit for camping. California Sport Fishing License required.

Learn More

Guides to help you fish San Joaquin River (Upper) with more confidence.