Maritime affairs bureaus of Fuzhou, Putian, Quanzhou, Xiamen and Zhangzhou today jointly activated the red warning, the highest level, to recall all ships to harbour, authorities with the Fujian provincial maritime affairs department said.
The department has already strengthened the offshore patrol and inspection to safeguard the safety of the ships.
Four rescue ships, three rescue jets and 65 tug boats have been put on emergency standby.
The Fujian observatory said Nanmadol was most likely to make a landfall over the southern part of Fujian, bringing gales and rainstorms.
The observatory forecast that the typhoon would coincide with an astronomical tide today, and waves are expected to reach 2-3.5 meters high in Fujian's coastal areas.
It also warned the the local governments as the typhoon could lead to potential torrential floods and landslides in some regions.