San Joaquin River Near Vernalis Flow Report
As of September 12, 2026, San Joaquin River Near Vernalis is flowing at 525 cfs with a gage height of 6.94 ft, holding steady over the past 24 hours. Source: USGS gauge #11303500, refreshed throughout the day.
San Joaquin River Near Vernalis at a glance
Live reading, 10-day trend, and the key gauge stats — how San Joaquin River Near Vernalis is running right now.
San Joaquin River Near Vernalis is flowing at 525 cfs, with the water sitting 6.94 ft at the gage. Flow has held roughly steady over the past 24 hours.
This is USGS gauge #11303500 in California. Over the past 10 days the average has been 591 cfs, peaking at 667 cfs.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the California flow report, or open San Joaquin River Near Vernalis on the interactive map.
Streamgage details
Historical Data
Streamflow Forecast
Over the next 5 days, San Joaquin R Nr Vernalis Ca is expected to hold near today's 525 cfs, toward roughly 520 cfs by 2026-09-17 (likely range 182-1488 cfs) -- drier than normal for the date.
Powered by PULSE — Snoflo’s forecast engine, trained on this gauge’s full record of storms, snowmelt, and dry spells.
Forecast vs seasonal normal
Engineering Data
Flow-duration statistics and observed peak-flow context computed from this gauge’s complete daily record (USGS #11303500).
Flow-duration & observed peak context
Estimate flows at an ungauged site
Drainage-area ratio transfer from this gauge . Most reliable for hydrologically similar sites in the same watershed with area ratios between roughly 0.5 and 1.5.
Percentiles are flow-duration values computed from this gauge’s observed daily record as archived by Snoflo. Return periods are Weibull plotting-position estimates from observed annual maxima, provided as general reference context only. Always verify against official USGS NWIS records. Part of Snoflo for Engineering.
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.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
San Joaquin River Near Vernalis
The river is fed by snowmelt from the Sierra Nevada mountains, and its flow is largely influenced by releases from upstream dams. The major tributaries of the San Joaquin River include the Merced, Tuolumne, and Stanislaus rivers, which also contribute to its flow. Seasonal trends in flow depend on the amount of snowmelt and rainfall, with peak flows typically occurring in the spring. The hydrology of the San Joaquin River is important for agriculture and drinking water supply in the Central Valley, but the river also faces challenges related to water management and habitat degradation. Interesting fact: The San Joaquin River is the second longest river in California, stretching over 330 miles from its headwaters in the Sierra Nevada to its confluence with the Sacramento River.
Nearby streamflow levels
Cross-check San Joaquin River Near Vernalis's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| San Joaquin River Near Vernalis Ca | 525 cfs |
| Stanislaus River A Ripon Ca | 166 cfs |
| Del Puerto Creek Near Patterson Ca | 0 cfs |
| Tuolumne River A Modesto Ca | 181 cfs |
| Grant Line Canyon Near Tracy Ca | 4,090 cfs |
| San Joaquin River Near Crows Landing Ca | 244 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near San Joaquin River Near Vernalis. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Knights Ferry 5.2 Wsw | 0 in |
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 San Joaquin River Near Vernalis in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when San Joaquin River Near Vernalis crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About San Joaquin River Near Vernalis
What is the San Joaquin River Near Vernalis flow rate right now?
As of September 12, 2026, San Joaquin River Near Vernalis is flowing at 525 cfs. The live value, gage height, and 24-hour trend are shown at the top of this page.
Is the San Joaquin River Near Vernalis running high or low right now?
Check the percent of median figure on this page: above 100% means San Joaquin River Near Vernalis is running higher than normal for the date, below 100% means lower. The 24-hour trend shows whether it's rising or falling.
Where does the streamflow data for San Joaquin River Near Vernalis come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 11303500. 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 San Joaquin River Near Vernalis 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.
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Get the free San Joaquin River Near Vernalis report — flow alerts, favorites, and history & forecasts, plus the free iPhone app.