Influence of the Madden-Julian Oscillation and Convectively-Coupled Kelvin Waves on tropical cyclone cyclogenesis over the eastern north Pacific and Atlantic Ocean basins

During the past few years, the real-time monitoring of convectively coupled atmospheric Kelvin Waves (CCKWs) and the Madden-Julian Oscillation (MJO) has become an important new tool for operational forecasters making tropical cyclone genesis forecasts. However, many questions remain open regarding the use of these atmospheric waves as a means for genesis prediction. While it is useful information to know the state of the MJO, or if a CCKW is nearing a system, quantifying the impact of these waves has been challenging. For example, a key question is whether the CCKWs in certain phases of the MJO are more effective at initiating tropical cyclones. A more quantifiable impact would be useful to the National Hurricane Center (NHC), which now makes probability forecasts of genesis for the next 5 days. The use of these atmospheric waves in a daily operational setting at NHC will be discussed and key case studies of recent storms that may have been influenced by these waves will be presented. In addition, CCKWs will be compared in various states of the MJO to help derive a more probability-based impact of these CCKWs based on the MJO phase and/or strength.