GUANGZHOU - China issued an alert for sea waves and storm surges after the strong tropical storm Nalgae landed in south China's Hainan Province on Tuesday afternoon, which later weakened to a tropical storm.

The forecast center of China South Sea under the State Oceanic Administration issued a yellow alert, the second-lowest alert level, at 2 pm, warning of sea waves of 2.5 to 5 m and storm surges of 40 to 100 cm from Tuesday afternoon to Wednesday, according to the alert.

Local weather forecast bureau in Guangdong Province said downpours would last in the next three days, bringing down the temperature by three to five degrees Celsius.

Nalgae, the No. 19 strong tropical storm this year, came ashore in the southernmost island province of Hainan at 12:30 pm, packing winds of 90 kilometers per hour at its center, and then weakened to a tropical storm.

China has a four-color coded sea wave and storm surge warning system. Red is the most serious level, followed by orange, yellow and blue.