Core Viewpoint - The recent high temperature and humidity in northern China, resembling the "return of southern weather," is attributed to the northward movement of the subtropical high pressure system, which has brought warm and moist air to the region [1][2]. Group 1: Causes of Recent Weather - The high humidity and heat in northern regions are closely linked to the northward shift of the western Pacific subtropical high pressure, which is currently controlling much of central and eastern China [2]. - The summer monsoon has pushed northward, reaching southern Northeast China and central and southern North China, bringing moisture and heat [2]. - Although maximum temperatures are around 30°C, high humidity significantly affects the perceived temperature, making it feel hotter than the actual temperature [2][3]. Group 2: Future Weather Patterns - Such humid and hot weather typically occurs in Beijing during the summer, particularly in mid to late July, due to the northward movement of the subtropical high pressure [4]. - This year's occurrence of humid weather is notably earlier than usual, by over 10 days, influenced by changes in the weather patterns across East Asia [4]. - The trend of increasing summer temperatures in Beijing is linked to global climate change, which may lead to more frequent occurrences of such weather if the warming trend continues [4][5]. Group 3: Health Impacts and Precautions - High temperature and humidity can impair the body's ability to regulate temperature, leading to dehydration and electrolyte imbalances, which may increase the risk of heat-related illnesses, especially in vulnerable populations [6]. - Recommendations for the general public include staying indoors during peak heat, staying hydrated, and avoiding strenuous outdoor activities [6]. - High-risk groups, such as the elderly and those with chronic conditions, should take extra precautions, including staying cool and hydrated, and seeking medical attention if necessary [6].

Group 1 - The central region of China, particularly the Yangtze River middle and lower reaches, is experiencing significant rainfall, with heavy rain expected to continue over the holiday period [1][2][5] - The rain is forecasted to shift southward, affecting regions in South China, with warnings for potential severe weather including thunderstorms and strong winds [2][5] - The northeastern region is experiencing a cooling trend due to the movement of cold air, contrasting with the hot and humid conditions in South China, where temperatures may feel above 40°C [6] Group 2 - Specific areas such as Anhui, Zhejiang, and Jiangxi are currently facing heavy rain and localized flooding, with some regions reporting extreme weather conditions [2][5] - The forecast indicates that the heavy rainfall will persist in the central and southern parts of China, with warnings for potential flash floods and landslides in vulnerable areas [3][4] - The temperature fluctuations in northern regions are notable, with cities like Harbin and Changchun experiencing much cooler weather compared to the high temperatures in southern cities like Nanning and Haikou [6]