“桦加沙”“博罗依”之后还有台风 今年为何扎堆出没？

Core Insights - The current typhoon season in China has seen an increase in both the number of typhoons generated and those making landfall compared to historical averages, particularly concentrated in the months of July to September [1][3]. Group 1: Typhoon Generation and Landfall - The number of typhoons generated from January to September is approximately 1.53 more than the average, while the number of landfalls is about 1.5 more than usual, with a significant concentration in the July to September period [1][3]. - The generation of typhoons has been delayed this year, with only two typhoons formed before the end of June, while the majority occurred between July and September [3]. Group 2: Factors Influencing Typhoon Activity - The increase in typhoon activity is influenced by several factors, including the position and strength of the subtropical high pressure, monsoon currents, and sea surface temperatures [3]. - In July and September, the subtropical high pressure was generally stronger and positioned more to the north and west than usual, providing favorable conditions for typhoon formation [3]. - High sea surface temperatures have also contributed to the generation and development of typhoons [3]. Group 3: Current Typhoon Activity - Currently, two typhoons are active in the Northwest Pacific and South China Sea, with Typhoon "Bolaoi" being particularly noteworthy as it has intensified and is expected to impact regions such as Hainan [8][9]. - The expected weather conditions from Typhoon "Bolaoi" include strong winds and significant rainfall, with potential accumulations of 250 to 400 millimeters in affected areas [9]. Group 4: Future Typhoon Developments - There is a possibility of another typhoon or tropical depression forming in the Northwest Pacific, with developments expected around October 3, which may subsequently approach the South China Sea [10][12]. - The potential new disturbance could impact parts of South China, necessitating heightened awareness and safety measures for maritime activities in the South China Sea and coastal areas [12].