OMB number: 4040-0019 expiration date: 06/30/2028 project abstract summary this project abstract summary form must be submitted or the application will be considered incomplete

The National Oceanic and Atmospheric Administration awarded a Cooperative Agreement to the University of Colorado (Regents of the University of Colorado, Office of Contracts and Grants) for $499,683 on September 1, 2026, under the Cooperative Institute (Inter-Agency Funded Activities) program (CFDA 11.405).

The award funds development of ensemble sensitivity-based and cluster tools to improve scenario-based extreme rainfall forecasting. The project addresses forecast challenges posed by flash flooding and high-impact winter precipitation by applying ensemble sensitivity analysis to diagnose relevant early forecast features associated with precipitation magnitude and timing, enabling real-time generation of information to improve hazard prediction within convection-permitting numerical weather prediction ensemble systems.

Performance takes place in Boulder, Colorado, with a period of performance through August 31, 2028. The Cooperative Institute program supports research and education in environmental sciences through cooperation between government, university, and nonprofit research institutions, with awards made on the basis of proposal evaluation, technical and administrative review, and external review where applicable.

Ensure the project abstract field succinctly describes the project in plain language that the public can understand and use without the full proposal. Use 4,000 characters or less. Do not include personally identifiable, sensitive or proprietary information. Refer to agency instructions for any additional project abstract field requirements. If the application is funded, your project abstract information (as submitted) will be made available to public websites and/or databases including usaspending.GOV. Funding opportunity number NOAA-OAR-ciao-2026-32241 assistance listing number(s): 11.405 applicant name austin coleman descriptive title of applicant's project development of ensemble sensitivity-based and cluster tools to improve scenario based extreme rainfall forecasting project abstract flash flooding poses a myriad of forecast challenges, particularly given the chaotic, highly variable nature of atmospheric conditions that govern flooding and high-impact winter precipitation. Such variability in convection- permitting numerical weather prediction (NWP) ensemble systems often presents a complex forecasting problem in that IT is difficult to quantify and communicate key forecast aspects like event timing or intensity using common probabilistic products (e.g., neighborhood probability of exceedance). If information specifically relevant to the prediction of these distinct hazards could be generated in real time, that information could potentially be used to improve their prediction. Ensemble sensitivity analysis (ESA) is a tool that presents the ability to do this, by diagnosing the most relevant early forecast features associated with the prediction of impacts, such as precipitation magnitude and timing, within a broader event. In turn, a significant opportunity exists to evaluate the use of ESA within an operational environment for flash flooding and winter weather at the hydrometeorological testbed (HMT) flash flood and intense rainfall (ffair) and winter weather (WWE) experiments. This project will directly address the capability for forecasters to interrogate specific flooding or winter weather attributes, like precipitation onset, and reveal the atmospheric features that drive them. This information will be used to inform forecast messaging for various hazards, and will be evaluated in a NOAA testbed environment.