BEIJING -- China's national observatory on Sunday issued a blue alert for typhoon Yagi which has strengthened ahead of its forecast landfall in the eastern coastal region.

Yagi, this year's 14th typhoon, is expected to make landfall on the coast between Wenzhou and Xiangshan in Zhejiang Province as early as Sunday evening, packing winds of up to 30 meters per second, the National Meteorological Center (NMC) said in a statement.

At 5 am Sunday, the eye of Yagi was 530 km offshore of the city of Taizhou, also Zhejiang.

The tropical storm will weaken after making landfall and continue to move northwest inland, the NMC said.

China has a four-tier, color-coded weather warning system, with red representing the most severe, followed by orange, yellow, and blue.

The NMC suggested local governments prepare for possible disasters, ships in affected areas return to port, and residents along the typhoon's path stay indoors until it passes.