Trinity River A Lewiston flow report

California, USA USGS #11525500 ↗

As of July 13, 2026, Trinity River A Lewiston is flowing at 444 cfs with a gage height of 14.04 ft, holding steady over the past 24 hours. Source: USGS gauge #11525500, refreshed throughout the day.

Stale data This gauge hasn’t reported in days (last reading unknown). The readings below may not reflect current conditions.
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Right now · latest observation
Trinity River A Lewiston
USGS gauge #11525500
444 cfs streamflow
Latest reading from this gauge.
Gage height
14.04ft
Water temp
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% of median
Since yesterday
↓ -1%
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Conditions summary

Trinity River A Lewiston at a glance

How Trinity River A Lewiston is running right now, where it sits on the map, and the key gauge stats.

Trinity River A Lewiston is flowing at 444 cfs, with the water sitting 14.04 ft at the gage. Flow has held roughly steady over the past 24 hours.

This is USGS gauge #11525500 in California. Over the past 10 days the average has been 450 cfs, peaking at 457 cfs.

Over the next 5 days, Trinity R A Lewiston Ca is expected to hold near today's 444 cfs, toward roughly 426 cfs by 2026-07-18 (likely range 282-644 cfs) -- running well below the seasonal normal.

For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the California flow report.

Trinity River A Lewiston on the map Open map →
Site IDUSGS 11525500
Last updated2026-07-13
Gage height, ft14.04 ft
Stream water level elevation above NAVD 1988, in ft1835.49 ft
Temperature, water, °C10.1 deg C
Streamflow, ft³/s444.0 ft3/s
Max recorded11,700 cfs
Streamflow outlook

Streamflow Forecast

Powered by PULSE — Snoflo’s Predictive Unified Learning & Simulation Engine, which learns from how this river has answered every past storm, snowmelt, and dry spell to forecast where it’s headed with a precision generic models can’t match.

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Historical context

How does this compare to past years?

Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.

Detailed forecast

Weather Forecast

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

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Deep dive

5-day forecast table

Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
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Long-term outlook

15-day forecast

Daily temperatures, snow, and rain projected over the next two weeks.

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About this location

Trinity River A Lewiston

It is important for water resource management, hydropower, and recreation. The main providers of water are snowmelt and precipitation. There are several dams and tributaries along the Trinity River, including the Trinity Dam and the South Fork Trinity River. Seasonal trends show high flow during spring and early summer, and low flow during fall and winter. Interesting facts include the Trinity River being one of the main rivers in California and home to several fish species, including salmon and steelhead. The river also serves as a source of irrigation and provides water for agricultural activities.

Regional streamflow

Nearby streamflow levels

Cross-check Trinity River A Lewiston's discharge against nearby gauges to spot whether the change here is local or regional.

Regional snowpack

Nearby snowpack data

Snowpack at SNOTEL stations near Trinity River A Lewiston. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.

Nearby recreation

Plan a trip

Reservoirs, boat launches, river runs, and fishing spots within driving distance of Trinity River A Lewiston.

River levels & flood safety

Read the level before you go
A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
Respect cold water
Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
Watch for swiftwater hazards
Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
Mind flash floods & releases
Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.

Track Trinity River A Lewiston in the Snoflo app

Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Trinity River A Lewiston crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.

FAQ

About Trinity River A Lewiston

Where does the streamflow data for Trinity River A Lewiston come from?

Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 11525500. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.

How often is the report updated?

USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.

What's the difference between discharge and gage height?

Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.

How is "percent of median" calculated?

Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.

What are flood stages, and is this river safe right now?

Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.

Can I get alerts when Trinity River A Lewiston rises?

Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.