Two tropical storms have forced mass evacuations and widespread transport shutdowns across Japan and Taiwan, with about 1 million people under evacuation orders in Japan and 6 million kept from work or school in Taiwan.
Tropical storms Mekkhala and Higos are bringing conditions that threaten landslides, floods and swollen rivers across Japan, as warm, moist air from both weather systems merges with a seasonal rain front to deliver heavy downpours to western regions.
Transport networks paralysed
More than 200 flights have been cancelled in Japan, while dozens of train services have been suspended and many expressways closed. In Taiwan, severe flooding shut down a section of the main north-south railway link.
Taiwanese authorities shut offices and schools on Friday in the southern regions of Kaohsiung, Pingtung and Tainan. Hsinchu closed from midday on Friday. Almost a metre of rain has fallen in parts of Pingtung since Thursday.
Chi, a dessert shop owner in Zhubei, described the conditions: "Last night the rain wasn't too bad. But this morning the rain didn't stop. The road outside was flooded up to the knees, and inside our shop it was a little below knee level."
Storm trajectories converging
Mekkhala shifted from typhoon to tropical storm status after moving over the southern Ryukyu Islands on Friday. The system is expected to gain speed and reach western and eastern Japan by Saturday.
Higos is forecast to approach eastern Japan and potentially make landfall around Saturday. The Japan Meteorological Agency said the combined impact of the storms and rain front could increase rainfall across much of the country.
Barrier lake evacuations
In Taiwan's Hualien county, authorities are removing nearly 200 residents from two townships downstream of a barrier lake that is filling rapidly. Barrier lakes form when rocks, landslides or other natural blockages create a dam across a river.
The precautionary evacuations follow a deadly incident last year when 19 people died in Hualien after a barrier lake breached during Super Typhoon Ragasa, releasing water and mud into homes.
No casualties have been reported in Taiwan from the current storm system.
What comes next
Both storms are expected to continue affecting the region through the weekend, with the meteorological agency forecasting continued heavy rainfall as the systems track toward Japan. Southern Taiwan relies on the summer and autumn typhoon season to replenish reservoirs after dry winters.