II 

118TH CONGRESS 

2D SESSION S. 5361 

To improve the lead time, accuracy, and dissemination of forecasts of 

atmospheric rivers throughout the United States, and for other purposes. 

IN THE SENATE OF THE UNITED STATES 

NOVEMBER 20, 2024 

Mr. PADILLA (for himself and Ms. MURKOWSKI) introduced the following bill; 

which was read twice and referred to the Committee on Commerce, 

Science, and Transportation 

A BILL 

To improve the lead time, accuracy, and dissemination of 

forecasts of atmospheric rivers throughout the United 

States, and for other purposes. 

1 Be it enacted by the Senate and House of Representa2 tives of the United States of America in Congress assembled, 

3 SECTION 1. SHORT TITLE. 

4 This Act may be cited as the ‘‘Improving Atmos5 pheric River Forecasts Act’’. 

6 SEC. 2. ATMOSPHERIC RIVERS FORECAST IMPROVEMENT 

7 PROGRAM. 

8 (a) IN GENERAL.—The Under Secretary, in collabo9 ration with the weather enterprise in the United States 


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1 and institutions of higher education, shall establish an at2 mospheric river forecast improvement program (in this 

3 section referred to as the ‘‘program’’). 

4 (b) PROGRAM ELEMENTS.—In carrying out the pro5 gram, the Under Secretary shall seek to reduce the loss 

6 of life and property and economic losses from atmospheric 

7 rivers through the development and extension of, and re8 search on, accurate, effective, and actionable forecasts and 

9 warnings, including by— 

10 (1) establishing quantitative atmospheric river 

11 forecast skill metrics that include the benefits of dy12 namical modeling, data assimilation, and machine 

13 learning improvements in the probabilistic forecasts 

14 of landfall location, extreme wind and precipitation, 

15 and cascading impacts; 

16 (2) developing an atmospheric river forecast 

17 system within a unified forecast system, and advanc18 ing next-generation coupled modeling systems, with 

19 the capability of providing seasonal to short-range 

20 atmospheric river forecasts that include forecast of 

21 snow accumulation and other hydrologic compo22 nents; 

23 (3) advancing scientific understanding of the 

24 roles of atmospheric rivers in subseasonal to seaVerDate Sep 11 2014 00:32 Nov 26, 2024 Jkt 059200 PO 00000 Frm 00002 Fmt 6652 Sfmt 6201 E:\BILLS\S5361.IS S5361

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1 sonal precipitation and probabilistic predictions at 

2 subseasonal and seasonal scales; 

3 (4) developing tools and improved forecast 

4 products to predict periods of active or inactive at5 mospheric river landfalls and inland penetration over 

6 the United States with a focus on addressing stake7 holder and public needs related to perceiving, com8 prehending, and responding to atmospheric river 

9 forecast improvements; 

10 (5) enhancing the transition of research to op11 erations through the testbeds of the National Oce12 anic and Atmospheric Administration, including the 

13 evaluation of physical and social science, technology, 

14 and other research to develop products and services 

15 for implementation and use by relevant stakeholders; 

16 and 

17 (6) incorporating social, behavioral, risk, com18 munication, and economic sciences, including by col19 lecting voluntary data regarding hazardous weather 

20 or water events. 

21 (c) INNOVATIVE OBSERVATIONS, DATA ASSIMILA22 TION, AND MODELING.—The Under Secretary shall en23 sure the program periodically examines, tests, and evalu24 ates the value of incorporating innovative observations, 

25 such as observations from radar, observations from crewed 


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1 or uncrewed aircraft, novel airborne and satellite-based 

2 measurements, data from ocean buoys, data from soil 

3 moisture monitoring systems, reservoir storage data, ob4 servations from mesonets, or any observations, measure5 ments, or data from other emerging technologies, with re6 spect to the improvement of atmospheric river analysis, 

7 modeling, forecasts, predictions, and warnings. 

8 (d) IMPROVED MODELING.— 

9 (1) IN GENERAL.—Under the program, the 

10 Under Secretary may improve modeling for precipi11 tation forecasts, with an emphasis on forecasting for 

12 complex terrain. 

13 (2) IMPROVED PRECIPITATION FORECASTS.— 

14 Improved precipitation forecasts pursuant to im15 proved modeling under paragraph (1) should support 

16 improved water resource management and resilience 

17 to extreme water-related events, from floods to 

18 drought, which may include the use of enhanced 

19 streamflow prediction. 

20 (3) ELEMENTS.—In improving modeling under 

21 paragraph (1), the Under Secretary may— 

22 (A) develop, test, and operationalize proto23 type high-resolution Atmospheric River Analysis 

24 and Forecasting System models through a re25 search and operations partnership with partners 


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1 outside the National Oceanic and Atmospheric 

2 Administration; 

3 (B) enhance data assimilation of current 

4 and new satellite and ocean observations; 

5 (C) improve data processing techniques; 

6 (D) use artificial intelligence and machine 

7 learning methods as applicable; 

8 (E) ensure the surface and subsurface ob9 servations of the ocean meet the needs of at10 mospheric river analysis and forecasting pre11 dictions on time scales from days, to weeks, to 

12 months, to seasons; and 

13 (F) improve or establish baseline weather 

14 monitoring service in areas that have histori15 cally experienced, or are predicted to experi16 ence, atmospheric rivers. 

17 (e) ATMOSPHERIC RIVER RECONNAISSANCE.— 

18 (1) IN GENERAL.—The Under Secretary shall 

19 acquire and sustain adequate crewed and uncrewed 

20 aircraft, scientific equipment, and personnel nec21 essary to meet mission requirements annually from 

22 November 1 through March 31 to— 

23 (A) ensure atmospheric river air reconnais24 sance observations are available throughout the 

25 expected seasons of atmospheric rivers; 


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1 (B) meet air reconnaissance and research 

2 mission requirements of the National Oceanic 

3 and Atmospheric Administration, including with 

4 respect to tropical cyclones, high-impact weath5 er, sea ice, atmospheric chemistry, climate, air 

6 quality for public health, fire weather research 

7 and operations, and other missions, including 

8 marine animal surveys, post-damage surveys, 

9 and coastal erosion reconnaissance; 

10 (C) ensure data and information collected 

11 by the aircraft are made available to all users 

12 for research and operations purposes; 

13 (D) participate in the research and oper14 ations partnership that guides flight planning 

15 and uses research methods to improve and ex16 pand the capabilities and effectiveness of atmos17 pheric river reconnaissance over time; 

18 (E) develop data management strategies to 

19 ensure that data and metadata are adequately 

20 stewarded, maintained, and archived in accord21 ance with collective benefit, authority to control, 

22 responsibility, and ethics principles (commonly 

23 known as ‘‘CARE’’ principles), findable, acces24 sible, interoperable, and reusable principles 

25 (commonly known as ‘‘FAIR’’ principles), and 


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1 the Foundations for Evidence-Based Policy2 making Act of 2018 (Public Law 115–435; 132 

3 Stat. 5529) and the amendments made by that 

4 Act, and preserve and curate such data and 

5 metadata in accordance with chapter 31 of title 

6 44, United States Code (commonly known as 

7 the ‘‘Federal Records Act of 1950’’); 

8 (F) maintain or establish within the Office 

9 of Oceanic and Atmospheric Research not fewer 

10 than one atmospheric river observatory, which 

11 shall include water vapor flux analyses and 

12 forecasts, radar and disdrometer precipitation 

13 analyses, and snow level radars in all States 

14 along the West Coast of the United States, in15 cluding Alaska, to ensure equal and comprehen16 sive coverage of that region; and 

17 (G) undertake such other additional activi18 ties as the Under Secretary, in consultation 

19 with the Secretary of the Air Force, considers 

20 appropriate to improve and grow the atmos21 pheric river reconnaissance mission. 

22 (f) IMPROVED ATMOSPHERIC RIVER HAZARD COM23 MUNICATION.—Under the program, the Under Secretary 

24 shall consider research and development activities to— 


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1 (1) as appropriate, develop and refine methods 

2 to categorize the intensity of atmospheric rivers on 

3 a quantitative scale and the impacts of such a scale 

4 in hazard communication; 

5 (2) develop best practices for communication of 

6 atmospheric river events and hazards across regions 

7 of the United States; 

8 (3) gather information from areas prone to at9 mospheric rivers regarding levels of knowledge and 

10 preparedness, including responses to early forecasts 

11 and warnings by the National Oceanic and Atmos12 pheric Administration; and 

13 (4) explore strategies and effectiveness of com14 municating that atmospheric river events are bene15 ficial at lower intensities versus hazardous at higher 

16 intensities. 

17 (g) PROGRAM PLAN.—Not later than 270 days after 

18 the date of the enactment of this Act, the Under Sec19 retary, in consultation with the Secretary of the Air Force 

20 or the Commander of the 53rd Weather Reconnaissance 

21 Squadron of the Air Force Reserve Command, shall— 

22 (1) develop a plan that details the specific re23 search, development, data acquisition, partnerships 

24 with institutions of higher education, and technology 

25 transfer activities, as well as corresponding resources 


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1 and timelines, necessary to achieve the goals of the 

2 program under subsection (b); 

3 (2) submit that plan to the Committee on Com4 merce, Science, and Transportation of the Senate 

5 and the Committee on Science, Space, and Tech6 nology of the House of Representatives; and 

7 (3) make that plan available to the public. 

8 (h) DEFINITIONS.—In this section: 

9 (1) INSTITUTION OF HIGHER EDUCATION.—The 

10 term ‘‘institution of higher education’’ has the 

11 meaning given that term in section 101(a) of the 

12 Higher Education Act of 1965 (20 U.S.C. 1001(a)). 

13 (2) SEASONAL; SUBSEASONAL; UNDER SEC14 RETARY; WEATHER ENTERPRISE.—The terms ‘‘sea15 sonal’’, ‘‘subseasonal’’, ‘‘Under Secretary’’, and 

16 ‘‘weather enterprise’’ have the meanings given those 

17 terms in section 2 of the Weather Research and 

18 Forecasting Innovation Act of 2017 (15 U.S.C. 

19 8501). 

Æ 


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