The Korea Meteorological Administration has tightened the criteria for sending heavy-rain emergency alerts to residents across South Korea [1].
These updates aim to reduce casualties as the region faces increasingly intense rainfall events. By refining the thresholds for emergency text messages, the government intends to provide faster, more accurate warnings that prompt immediate evacuation from high-risk areas [1].
Under the new system, emergency alerts are triggered if rainfall reaches 100 mm or more per hour [2]. Additionally, alerts are sent if rainfall hits 85 mm or more per hour with a 15-minute burst of 25 mm or more [2].
These standards are more stringent than previous criteria, which triggered alerts when rainfall reached 72 mm or more per hour, or when it reached 50 mm or more per hour combined with 90 mm or more over three hours [1].
"If a 'beep' alarm sounds on your mobile phone, you must immediately leave the vicinity of water or underground areas," reporter Hwang Yun-tae said [3].
The system utilizes emergency text messages to notify the public when extreme heavy rain criteria are met. Once the alert is received, listeners are instructed to evacuate their current locations immediately to avoid flash floods or landslides [1].
"When disaster-level heavy rain exceeding 100mm per hour falls, additional emergency texts are sent," a YTN news anchor said [3].
The initiative began as a pilot program in 2023 within the Seoul metropolitan area before expanding nationwide [1], [3]. The tightened criteria officially took effect starting in the summer of 2026 [1].
Officials said that the refined thresholds make the alert system more detailed to better protect human life during extreme weather events [3].
“If a 'beep' alarm sounds on your mobile phone, you must immediately leave the vicinity of water or underground areas.”
The shift toward higher, more specific rainfall thresholds indicates that South Korea is adapting its disaster management to a new baseline of 'extreme' weather. By focusing on short-term intensity—such as 15-minute bursts—the agency is prioritizing the detection of flash-flood triggers over general accumulation, reflecting a strategy to minimize death tolls in urban environments where drainage systems can be overwhelmed rapidly.
