*Tapah = A typhoon.
*Busan = The country’s second-largest city.
Tapah was expected to pass about 130 kilometers southeast of Yeosu, South Jeolla Province, at around 6 p.m. Sunday and 170 km south of Busan at around 9 p.m. The closest it was expected to be to the country’s second-largest city was 50 km at around 10 p.m. It would then pass about 60 kilometers northeast of Korea’s easternmost islets of Dokdo in the East Sea at around 6 a.m. Monday, according to the weather agency.
What I was wondering is the bolded phrase.
The closest what is 50 km? A distance? And 50 km of what? In a 50 km radius, or 50 km to the southeast?
I'm not a native speaker so I'm not sure you could omit some parts like this in a official written paper. Inform me please if this is written well or not. If it is done correctly, how could a native speaker notice what is omitted or not and interpret this naturally? Just from background knowledge and the context?