Japan has declared a level 5 emergency warning, the highest level, after heavy rain struck Chiba Prefecture and several other eastern regions, causing flooding and severe landslide risks. More than 100,000 households have been ordered to evacuate.
On 13 Aug 2026 GMT+7, the Japan Meteorological Agency announced a level 5 emergency warning—the highest alert—for landslides in Chiba City and Ichihara City in Chiba Prefecture. The agency also issued the same level warning for heavy rain across multiple areas following continuous downpours that have raised the risk of severe flooding and landslides.
The heavy rain warning covers several cities in Chiba Prefecture, with rainfall rapidly increasing in many areas. In Chiba City, rainfall exceeded 107 millimeters, while Yachiyo City recorded 115 millimeters. There is a very high likelihood that severe flooding and river overflow disasters have already occurred. Authorities have urged residents to take immediate safety measures due to life-threatening conditions.
Officials warned that this rain event is unprecedented in intensity, unlike anything the population has experienced before. Local governments in the city and over 10 other areas have issued the highest-level evacuation orders, calling on residents not to wait for conditions to worsen but to move promptly to safer or higher ground.
The Japan Meteorological Agency also detected heavy rain cloud formations over the northwest, northeast, and southern parts of Chiba Prefecture. They warned that additional level 5 emergency warnings for heavy rain may be issued in other areas, urging residents in vulnerable locations to urgently take protective actions before further alerts are announced.
Japan's warning system defines level 5 as the highest alert, indicating that a disaster is occurring or imminent. Residents are advised to act immediately to save their lives and not to wait until the situation becomes more severe before evacuating.
Source: NHK