Summary: As tropical cyclones (TCs) move across the oceans, they begin to expand each day around sunset, with clouds reaching hundreds of miles from the center by the following afternoon. This daily “exhale” of the clouds is a feature of what we call the TC diurnal cycle. This study looks at the this cycle in a forecast model version of a strong hurricane. The “exhales” are seen during multiple days with large, very regular expanding signals in temperature, moisture, wind, and rainfall. This study could help us better understand how the TC diurnal cycle affects TCs and how we can recognize it in forecast models.
Important Conclusions:
- The daily “exhale” or expansion of the TC clouds affects the structures of both real-world hurricanes and storms in forecast models.
- Scientists can use findings from this study to better recognize the TC diurnal cycle in forecast models and to understand how it affects the structure and intensity of TCs.
You can read the paper online at https://journals.ametsoc.org/doi/abs/10.1175/MWR-D-18-0130.1