Extreme weather events are shaped not only by atmospheric dynamics but also by ocean conditions that evolve from subseasonal to decadal timescales. Variability in the upper ocean modulates sea surface temperature patterns and air–sea exchanges of heat, moisture, and momentum. These coupled processes can precondition the atmosphere, influence storm development and persistence, and affect the likelihood, intensity, and duration of extremes such as heatwaves, heavy precipitation, droughts, tropical cyclones, and compound coastal flooding. This session invites contributions that advance understanding of how upper-ocean processes and air–sea interactions modulate extreme weather and ocean phenomena at subseasonal, seasonal, interannual, and decadal timescales. We welcome observational, modeling, and theory-based studies, including process diagnostics, coupled predictability experiments, case studies of notable extremes, and evaluations of model physics and parameterizations. Contributions that link ocean states to specific extreme-event mechanisms, and that identify pathways for improved prediction and risk assessment, are particularly encouraged.

• A - Atmospheric Sciences