This Autumn Rain is the Heaviest in 74 Years for This Period
Yesterday morning, the autumn rain that had lasted for three days finally came to an end. According to the chief forecaster, this rainfall event was characterized by its long duration, large cumulative rainfall, and gentle intensity; the entire rainfall process lasted over 70 hours, with the city’s average rainfall being the highest for early October since 1951, ranking first in historical records for the same period.
The rainfall began at 4:00 AM on October 8 and ended at 5:00 AM on October 11, representing a typical continuous autumn rain. The city’s average precipitation was 88.1 millimeters, with the urban area averaging 104.5 millimeters; the maximum precipitation was recorded at Jingxian Home in Daxing District, reaching 178.5 millimeters.
In addition to the city’s average rainfall ranking first in historical records for the same period, among the 20 national-level weather stations in the city, except for the three northern mountain stations, all other stations broke historical records for precipitation during the same period.
Why was this autumn rain so heavy and prolonged? The explanation lies in the position of the subtropical high pressure system being significantly further north than usual this year, with stronger intensity. The warm, moist air currents on the periphery of the subtropical high could thus affect North China, while interacting with the low-level returning cold air. The prolonged confrontation between warm and cold air masses resulted in continuous rainfall.
This rainfall differs from summer rainfall in its formation mechanism. During summer, warm conditions at lower levels combined with cold conditions at higher altitudes easily create convective weather. Currently, with cold conditions at ground level and warm conditions at higher altitudes, the rainfall primarily consists of stable precipitation.
Based on current weather pattern analysis, Beijing will continue to experience mainly cloudy weather today, with scattered light rain or drizzle possible in some southern districts and mountainous areas. Additionally, another round of cloudy, rainy, and cooling weather is expected to affect Beijing from October 15 to 17. Following the rain, northerly winds of force 3-4 are anticipated, with temperatures expected to drop. Please stay updated with the latest weather forecasts and take precautions in advance.
