Core Viewpoint - A strong cold air mass is affecting Beijing, leading to an early onset of winter, with temperatures expected to drop significantly starting October 17, 2023 [2][4][6]. Summary by Sections Weather Forecast - The cold air mass is the most extensive and intense affecting China this year, with temperatures expected to drop by 4°C to 8°C across most regions from October 15 to 19, 2023 [2][4]. - Beijing is predicted to experience a significant temperature drop, with nighttime temperatures falling to around 4°C from October 17 to 18, 2023 [4][6]. Winter Onset Criteria - According to national standards, winter is defined as the first occurrence of a continuous 5-day sliding average temperature below 10°C [7]. - Historically, the average winter onset date for Beijing from 1991 to 2020 was October 31, but this year it is expected to be significantly earlier, around October 18, 2023 [7][8]. Historical Context - The earliest recorded winter onset in Beijing was October 16, 2021, with the potential for this year to tie for the fourth earliest winter onset [8]. Health Implications - The drop in temperature can lead to various health risks, including respiratory issues, cardiovascular diseases, and exacerbation of chronic conditions [9][10][11]. - Recommendations for health management during this cold spell include maintaining warmth, hydration, regular health monitoring, moderate exercise, and a consistent sleep schedule [12][13][14][15].