Typhoon "Bavi" suddenly "evolves into a two-stage system"? Chief forecaster of the Central Meteorological Observatory explains the key variables.

Why does Typhoon "Bavi" fluctuate between strong and weak? Wang Jian, chief forecaster of the Central Meteorological Observatory, said that Typhoon "Bavi" maintained its strength for a period of time after weakening to a typhoon level. During this period, the convective structure near the center began to reorganize and gradually formed a double eyewall structure. With about one day before landfall, as the outer eyewall and inner eyewall sequentially contract, the overall intensity of the typhoon is expected to slightly increase. At the same time, the continuous influx of southwest monsoons in the lower atmosphere provides a constant supply of energy for the typhoon; and the warm sea surface underneath also plays a positive role in sustaining and promoting the development of the typhoon. Therefore, there is still a possibility of further strengthening of the typhoon intensity in the future period. It is important to note that during the maintenance of the double eyewall structure, the typhoon intensity often shows some fluctuating characteristics. Specifically, the intensity will undergo a stage change of initially strengthening, then weakening due to the collapse of the inner eyewall, and finally completing a re-intensification process with the completion of the inner eyewall replacement.