Hong Kong experienced its first black rainstorm warning of 2026 on Monday evening, issued by the Hong Kong Observatory for an hour starting at 8:35 pm. This top-tier alert signifies rainfall exceeding 70mm per hour, with reports of over 100mm in the Sha Tin district. The warning was subsequently downgraded to red, then amber, and finally cancelled by 10:45 pm. The intense rainfall caused flooding in various locations, including Tin Shui Wai, San Tin, Yuen Long, and Sha Tin, prompting emergency responses from the Drainage Services Department, which deployed over 110 teams. MTR services saw temporary closures of four station exits, and some road lanes were shut due to inundation. The Hospital Authority suspended night services at family medicine clinics, and cross-border high-speed rail services were affected.