Rain is pummeling South Korea this week, in some places falling faster than ever recorded in the country’s history. At least nine are dead — and more are missing — in flooding that has put parts of the capital Seoul underwater. Rescue workers have evacuated more than 500 people from the city. Many in Seoul have coped with downed power lines and power outages, including in the famously posh Gangnam neighborhood. The World’s Patrick Winn has been following the story.