Orographically trapped coastal wind events in the Pacific Northwest and their oceanic response

Three ageostrophic, Orographically trapped wind events in the coastal zone of the Pacific Northwest are examined. Time series of wind speed, wind direction, air temperature, sea level pressure, ocean currents, and ocean temperature are utilized to establish the general features of these events and to characterize the oceanic response. It is suggested that these atmospheric events are highly nonlinear bores or gravity currents, rather than quasi‐linear Kelvin waves. Observed oceanic responses include a drop in sea surface temperature (SST) of 1°–3°C offshore to approximately 150 km (approximately the atmospheric Rossby radius) and a rise in SST of similar magnitude within ∼15 km of the shore. A set of reduced‐gravity, fully nonlinear single layer models is utilized to investigate the dynamics of the atmospheric features and their oceanic response, and a possible air‐sea interaction. The models reproduce several of the first‐order features of the air and sea phenomena, such as the development of the atmospheric front, and the wake of near‐inertial waves in the ocean.