Summary: The Madden-Julian Oscillation (MJO) is an eastward-moving disturbance of clouds, rainfall, wind, and pressure that circles the earth in the tropics and returns to its starting point every 30 to 60 days, on average. One part of the MJO is stormy and wet and supports the development of thunderstorms, and another part is sunny and dry and generally prevents thunderstorms from forming.
Thunderstorms are necessary for tropical cyclones (hurricanes and typhoons) to form and become more intense. This study looked at whether the MJO can be used to help predict whether tropical cyclones in the north Atlantic Ocean and the north Pacific Ocean east of the International Dateline will intensify rapidly or not.
Important Conclusions:
1. Rapid intensification events and the MJO tend to move with each other from west to east across the hemisphere suggesting a relationship between the two.
2. Rapid intensification is most likely to occur when the MJO is neither stormy and wet nor sunny and dry near the tropical cyclone.
3. The addition of information about the MJO does not improve forecasts of rapid intensification. This is likely because the information about the MJO is already available in the forecast models in a different form.
Read the study at https://journals.ametsoc.org/waf/article/doi/10.1175/WAF-D-19-0209.1/348644/The-relationship-between-the-Madden-Julian?searchresult=1.
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