Prof. Bin Wang from the University of Hawaii visited JPL on Wednesday, August 5. He is a renowned expert on hurricane research and atmospheric dynamics. He led a proposal to NASA Hurricane Science Research Program (ROSES08) last year, in which Brian Kahn and I are JPL Co-Is. The proposal has been selected. His visit thus marked the official start of our collaborations. Bin presented very impressive WRF simulations of concentric eyewall replacement to form annular hurricane, which is a type of “monster” hurricanes that have high intensity and are hard to dissipate. Cloud microphysics seem to play an important role in the transition of concentric eyewall to annular hurricanes by affecting convective heating and thus vertical and horizontal structure of vorticity and winds. We will use satellite observations to identify favorable environmental conditions for the eyewall replacement cycle and hurricane genesis. There may be problems with availability of soundings near severe storms. However, combining multiple satellite measurements, we are hopeful that our research will provide insights for improving hurricane forecasts.