Michael J Deflorio¹, Duane Edward Waliser², F Martin Ralph³, Luca Delle Monache³, Peter Gibson⁴, Bin Guan⁵, Alex Goodman², Zhenhai Zhang⁶, Alexander Gershunov¹, Tamara Shulgina⁷, Kristen Guirguis⁸, Shakeel Asharaf⁹, Aneesh Subramanian¹⁰, Frederic Vitart¹¹, Hai Lin¹² and Arun Kumar¹³, (1)Scripps Institution of Oceanography, Center for Western Weather and Water Extremes (CW3E), La Jolla, CA, United States, (2)NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States, (3)Scripps Institution of Oceanography, UC San Diego, Center for Western Weather and Water Extremes, La Jolla, CA, United States, (4)JPL, Pasadena, United States, (5)University of California, Los Angeles, Joint Institute for Regional Earth System Science and Engineering, Los Angeles, CA, United States, (6)Scripps Institution of Oceanography, UC San Diego, Center for Western Weather and Water Extremes, La Jolla, United States, (7)University of California San Diego, La Jolla, United States, (8)Scripps Institution of Oceanography, La Jolla, CA, United States, (9)NASA Jet Propulsion Laboratory, Pasadena, United States, (10)University of Colorado at Boulder, Boulder, CO, United States, (11)ECMWF, Reading, United Kingdom, (12)Meteorological Research Division, Environment and Climate Change Canada, Dorval, QC, Canada, (13)NOAA/NCEP, College Park, MD, United States