Streamflow forecasts for Western U.S. water agencies and utilities
From Sierra snowmelt to atmospheric rivers, Western water managers face some of the most complex forecasting conditions. HydroForecast helps agencies and utilities protect communities, meet regulatory requirements, and make the most of every drop.
Stay ahead of Western water extremes
Western water conditions are never average. HydroForecast is built for the extremes — atmospheric rivers, fire-affected basins, and multi-year drought — when accurate forecasts matter most.
Atmospheric rivers
When a narrow band of moisture makes landfall, the difference between a well-managed reservoir and an emergency can come down to forecast accuracy. HydroForecast provided early warning at Folsom Reservoir 7 days before the February 2025 AR arrived — with 27% lower error than the RFC forecast.
Fire-affected basins
Wildfires reshape how water moves across a landscape overnight — stripping vegetation, accelerating runoff, and making existing models obsolete. HydroForecast integrates daily satellite vegetation data so forecasts adapt to post-fire conditions as they evolve, not as they were.
Drought conditions
When reservoirs are under pressure and allocations are tight, the last thing you need is a forecast built on historical patterns that no longer hold. HydroForecast Seasonal gives water managers reliable advance notice to make allocation and operational decisions before conditions reach a crisis point.
How FIRO is transforming reservoir operations
Forecast-Informed Reservoir Operations (FIRO) gives water managers the flexibility to make release and storage decisions based on what forecasts say is coming — not just what historical guide curves dictate. For California reservoirs managing flood risk and water supply in the same season, that flexibility can make the difference between a crisis and a well-managed event.
Sonoma Water has been using HydroForecast to inform FIRO decisions since 2022. Watch how their team puts it into practice.
Watch the Sonoma Water webinar
Forecasts for the West's largest water manager
Upstream Tech has been selected by the U.S. Bureau of Reclamation to bring AI river forecasts to ~20 key sites across the Western U.S. This multi-year partnership showcases the hydrologic science, the operational rigor, and the institutional fit of HydroForecast at any large utility or agency in the West.
Partnership highlights
Snow forecasting for the Western water year
Snowpack accumulation, rain-on-snow events, and spring snowmelt are some of the most consequential and difficult forecasting challenges in the Western U.S. The weeks around peak runoff are when accuracy matters most and when traditional models tend to break down.
HydroForecast reads more from sparse snow observations than traditional methods — enabling confident water supply planning across hydropower, irrigation, and municipal demand.
Explore snow forecasting
HydroForecast outperformed the next best model during the snowmelt season by 41% — exactly when water managers need reliable forecasts.
Accurate forecasts that pay off in day-ahead markets
CAISO reforms and the new Extended Day-Ahead Market (EDAM) reward operators who can forecast water — and price — with conviction. Western hydropower fleets use HydroForecast to capture more value, hour by hour.
CAISO customers earn more revenue per MW
- 33%
- reduction in day-ahead forecast errors for Western hydropower operators using HydroForecast.
Navigating the new EDAM market and CAISO reforms
As EDAM goes live in 2026, hydropower producers equipped with strong forecasting tools will be best positioned to thrive in this new landscape, improving both their financial performance and their contribution to grid reliability across the West.
Forecasting for environmental flows
Compliance, fish & wildlife flows, and ungauged tributaries — the hardest forecasting problems in the West also have the highest ecological stakes. We work alongside water agencies, researchers, and NGOs to improve environmental impact.
Forecasting where gauges don't exist
More than 80% of streams in the Western U.S. have no gauge — but water managers still need to account for every tributary, meet environmental flow requirements, and report on water rights.
HydroForecast delivers streamflow forecasts in ungauged basins, so agencies, utilities, and conservation groups can manage flows and meet compliance obligations without waiting on new infrastructure.
Supports
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Active in the Western water community
We're regular participants in the conferences, working groups, and professional organizations that shape Western water management and hydrology.
2026 events & memberships
