The Los Angeles area in the United States has experienced flash floods and mudslides
At the beginning of this month, the Los Angeles area in the United States experienced severe wildfires, which destroyed the local vegetation, resulting in loose soil and a significant decrease in its water absorption capacity. From the 25th to the 29th, due to persistent rainfall, the Los Angeles area experienced heavy to torrential rains, with locally extreme heavy rain, and the accumulated precipitation reached 80–180 millimeters (Figure 1). This led to secondary disasters such as flash floods and mudslides in the area.
It is expected that from January 30th to 31st, there will be light rain or showers in the Los Angeles area of the United States. From February 5th to 7th, under the combined influence of the northeast Pacific low-pressure system moving eastward and southward, and the subtropical warm and moist airflow (Figure 2), the Los Angeles area will experience a period of heavy precipitation. The total accumulated rainfall can reach 15–25 mm, with locally over 35 mm (Figure 3). Thus, there is still a need to guard against geological disasters such as flash floods and mudslides.
Figure 1. Accumulated precipitation (unit: mm) at the Global Exchange Station in the Los Angeles area from January 25th to 29th, 2025 (Beijing time)
Figure 2. Potential height at 500 hPa (contours) and wind field at 850 hPa (barbs) over North America at 20:00 BT (Beijing Time) on February 5th, 2025
Figure 3. Forecast of accumulated precipitation in the Los Angeles area, USA, from February 5th to 7th, 2025 (Beijing Time) (Unit: mm)
Author: Huo Da Reviewer: Cai Xiangning
English reviewer:Wang Yi Issue approver:Dai Kan