The Japan Meteorological Agency failed to issue critical linear precipitation zone forecasts due to a system failure on Monday [1].

These warnings are vital for early evacuation and disaster mitigation during extreme rainfall events. The failure left residents in high-risk areas without official alerts while weather conditions met the criteria for emergency warnings.

The system trouble began at 5:30 p.m. on Monday when the first attempt to publish a forecast failed [1]. Between 7 p.m. and 8:30 p.m. that same evening, conditions met the criteria for warnings three additional times, but the information was not released [1].

The failure affected the agency's overall system, specifically impacting the western part of Kochi Prefecture and Tokushima Prefecture [1]. As of 7:40 p.m. on Monday, the agency reported that linear precipitation zone forecasts and occurrence information were still not being properly published [2].

Kenichi Takahashi, director of the Meteorological Monitoring and Warning Center within the agency's forecast division, said the agency is investigating the cause of the trouble. He said that a lack of prior checks contributed to the failure.

"We want to reflect on the fact that the preliminary checks were insufficient," Takahashi said. "However, typhoons do not wait for such situations, so we want to do everything we can to respond now," he said [1].

The agency continues to investigate why the system failed to trigger the alerts despite the meteorological data meeting the necessary thresholds for public warning.

“The system trouble began at 5:30 p.m. on Monday when the first attempt to publish a forecast failed.”

The failure of the Japan Meteorological Agency's automated warning system highlights a critical vulnerability in the nation's disaster prevention infrastructure. Because linear precipitation zones cause sudden, intense flooding and landslides, the absence of these specific 'just-before' forecasts significantly reduces the window for residents to seek safety, potentially increasing casualties during active typhoon seasons.