CW3E Adds New Radiosonde Launch Site at Seven Oaks Dam

November 11, 2022

CW3E staff Hillary Beckmeyer (Field Researcher) and Ethan Morris (R&D Engineer) inaugurated a new weather balloon launch site at Seven Oaks Dam, 35 miles upstream from Prado Dam, within the Santa Ana River Watershed. Between 7-8 November 2022, a dynamic storm system featured a landfalling atmospheric river (AR) combined with a potent upper-level trough to produce strong upslope moisture flux and heavy precipitation. The launches at Seven Oaks Dam were coordinated with CW3E staff at three other locations: Scripps Pier, Yuba Water Agency in Marysville, and UC Davis Bodega Marine Lab. For further details on sampling the AR event, a summary can be found on the CW3E Sounding Google Drive.

CW3E placed a 20’ modified seavan on-site prior to the storm to have a dry space for launching and monitoring meteorological balloons. The new launch site at Seven Oaks Dam provides for more spatially comprehensive observations and improved context for meteorological site instrumentation already in place at the dam.

CW3E, with a host of partners, is currently assessing the viability of Forecast Informed Reservoir Operations (FIRO) at nearby Prado Dam, and will use the enhanced monitoring at Seven Oaks Dam to learn more about AR structure and evolution in southern California to improve upon weather and water forecasts. The goal is for the additional data collected from Seven Oaks Dam as part of FIRO, amongst a large suite of data collection, modeling, and other studies, to be integrated into decisions to retain or release water from Prado Dam.

CW3E is grateful to have such supportive partnerships in this endeavor with the Orange County Water District (OCWD), US Army Corps of Engineers (USACE), and San Bernardino County Public Works (SBCPW). Additionally, the assistance of the security team at the dam was instrumental in facilitating access throughout the entirety of the event.