HB 4302 would accelerate subseasonal to seasonal precipitation forecasts for water management in the western United States by amending existing law to establish pilot projects within NOAA’s Weather Research Program. It also creates a nationwide atmospheric river forecast improvement program designed to develop next-generation forecast systems, metrics, and transfer mechanisms to operations.
The bill authorizes $15 million per year for 2026–2030 to fund the pilot and related activities and includes a five-year sunset for the pilot authority. The package emphasizes collaboration with NOAA, the Weather Service, academia, and industry to advance higher-resolution modeling, data assimilation, and probabilistic forecasts that inform decision-making during atmospheric river events and related hydrologic impacts.
At a Glance
What It Does
The bill establishes a pilot project within NOAA’s Weather Research Program to improve subseasonal-to-seasonal precipitation forecasts for water management in the western U.S., and it creates an Atmospheric River Forecast Improvement Program to develop forecasts capable of predicting landfall, wind, snow, and hydrologic impacts.
Who It Affects
NOAA, the National Weather Service, universities and industry partners, and federal, state, and local water managers who rely on precipitation forecasts for water resource planning and hazard mitigation.
Why It Matters
Improved forecast skill can reduce flood risk, optimize water storage and releases, and support decision-making for infrastructure and emergency management tied to atmospheric river events.
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What This Bill Actually Does
The bill reorients NOAA’s forecast research toward two core efforts. First, it amends the Food Security Act to require at least one pilot project within the Weather Research Program that focuses on improving western U.S. precipitation forecasts.
The pilot emphasizes higher-resolution models, better representation of the atmospheric boundary layer and mountainous terrain, and more accurate predictions of rain-versus-snow and storm tracks. The aim is to produce measurable operational improvements for water managers who rely on forecasts for reservoir operations and drought planning.
Second, the legislation creates an Atmospheric River Forecast Improvement Program with the goal of reducing life and property losses from atmospheric river events. This program would pursue forecast system integration, probabilistic guidance, and tools to predict active versus inactive landfalls, while also advancing data assimilation, machine learning, and public-facing information.
It envisions closer collaboration with weather industry partners and academia, and it requires a concrete plan and budget to be presented to Congress. The bill also contemplates testbeds and technology transfer to ensure research findings reach operations, with an explicit emphasis on timely, actionable products for stakeholders.
Finally, the plan includes reconnaissance and observation enhancements, including aerial reconnaissance capabilities when warranted by atmospheric river and tropical cyclone activity, and a focus on effective hazard communication.
The Five Things You Need to Know
The bill adds a pilot project inside NOAA’s Weather Research Program to improve western U.S. precipitation forecasts.
It creates an Atmospheric River Forecast Improvement Program to develop probabilistic forecasts and end-to-end forecast systems.
An annual $15 million funding line is authorized for 2026–2030 to support the pilot and related activities.
A public plan with timelines and resource needs must be released within 270 days of enactment, followed by annual budget submissions.
The program integrates advanced observations, data assimilation, AI/ML methods, and operations transfer through NOAA testbeds.
Section-by-Section Breakdown
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Short Title
This act may be cited as the “Improving Atmospheric River Forecasts Act.” It establishes the framework and terminology used throughout the bill and sets the stage for the two main program tracks: subseasonal-to-seasonal forecasting pilots and atmospheric river forecast improvements.
Subseasonal to Seasonal Forecasting Pilot Projects
The bill amends the Food Security Act of 1985 to establish at least one pilot project within NOAA’s Weather Research Program. The pilot’s objectives include improving horizontal and vertical model resolution for mountainous terrain, better modeling of the boundary layer and atmospheric rivers, and resolving winter circulation and storm-track prediction challenges. It also calls for developing tools to predict active or inactive atmospheric river landfalls and inland penetration, with coordination between NOAA’s Office of Oceanic and Atmospheric Research and the National Weather Service. An annual appropriation of $15 million is authorized for 2026–2030 to support these activities, and the authority ends five years after enactment. The pilot is expected to build on and implement recommendations from the National Weather Service’s 2019 “Subseasonal and Seasonal Forecasting Innovation” report and to collaborate with higher education institutions and existing NOAA entities.
Atmospheric Rivers Forecast Improvement Program
This section requires the Under Secretary to establish an atmospheric river forecast improvement program in cooperation with the weather industry and academic partners. The program’s goals include creating forecast–skill metrics, developing a unified forecast system that spans seasonal to short-range scales, and advancing understanding of atmospheric rivers’ role in precipitation. It also mandates tools to predict landfall timing and inland penetration, while ensuring research transitions into operations via NOAA testbeds. A plan outlining research, data acquisition, partnerships, and resource needs must be public within 270 days, followed by annual congressional budget submissions. The Under Secretary is authorized to pursue high-resolution modeling, enhanced data assimilation, AI/ML applications, and improved weather monitoring in regions historically affected by atmospheric rivers, with reconnaissance resources (aircraft, equipment, personnel) to support hurricane hunter and atmospheric river missions where appropriate.
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Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- NOAA and the National Weather Service, through improved forecast accuracy and operational tools that can be deployed in routine public-facing products and warnings.
- Western state and local water managers, utilities, and reservoir operators who rely on accurate precipitation forecasts for flood control, drought mitigation, and water supply planning.
- Universities and research centers with expertise in western precipitation, hydrology, and atmospheric science that collaborate with NOAA and contribute to modeling and data assimilation advances.
- The weather industry partners who will participate in testing, validating, and operationalizing forecast improvements, potentially enabling new products and services.
Who Bears the Cost
- NOAA funding and resource allocation to implement pilots and develop new forecast systems.
- U.S. taxpayers bearing the upfront costs of federal program expansion and capability upgrades.
- State and local governments and water agencies that may need to adapt to new forecast products and decision-support tools.
- Academic and industry partners that invest time and resources to develop and validate new forecasting methods and transition research into practice.
Key Issues
The Core Tension
Should the federal government devote fixed, five-year funding to exploratory pilots and a new forecast-improvement program that may yield substantial advances but requires rapid transition to operations, or risk delayed implementation and uneven benefits given the complexity of atmospheric river forecasting and the varied needs of western water systems?
The bill envisions a multi-year investment in forecast science with a clear sunset for the pilot authority, recognizing the need to transition promising research into sustained operational capabilities. It raises questions about long-term funding, integration with existing NOAA programs, and the risk that pilot results may not fully translate to practice in some regions or over diverse atmospheric river regimes.
A key tension is balancing the pursuit of advanced modeling and data assimilation with the practical realities of operational constraints, data latency, and stakeholder readiness. The plan’s reliance on public sharing of sensitive, improved forecast products also warrants attention to governance and data stewardship.
These trade-offs will shape whether the forecast improvements translate into real-world resilience.
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