This is the 126th most frequent Japanese word.
北上
"北上" means "northward movement" or "going north."
北上 is used here as a verb meaning 'to move north.' It describes the action of the typhoon traveling in a northerly direction.
台風が北上している。
The typhoon is moving north.
北上 is used as a compound verb here, '北' means 'north' and '上' indicates movement upwards, together representing movement towards the north.
列車は北上する予定です。
The train is scheduled to head north.
Here, 北上 is used to describe the route taken during travel. It indicates the directional movement towards the north.