HANGZHOU -- Heavy rainstorms brought by Typhoon Saomai will hit the coastal and southern parts of east China's Zhejiang Province, the provincial meteorological observatory has forecasted.

Heavy rains will hit Wenzhou, Taizhou, Ningbo and the eastern part of Lishui in Zhejiang from Wednesday night till Friday, with winds gusting 70 to 120 km per hour, said the observatory.

The center of Saomai, the name of the planet Venus in Vietnamese, was located at sea 1,000 km east-southeast of Wenzhou, with wind speeds of up to 144 km per hour at 5:00 a.m. Wednesday.

The typhoon is still gathering strength and its center is moving northwest at a speed of 25 to 30 km per hour, said the observatory.

The observatory warned of possible landslides and mud-rock flows in the mountainous areas of the province and advised all vessels to return immediately to harbor.

Typhoon Saomai, the eighth to hit China this year, is expected to make landfall Thursday afternoon or night between central Zhejiang and the northern coastal area of neighboring Fujian Province.

Another tropical storm, Bopha, 1,000 km behind Saomai, is moving westward toward China at a speed of 20 km per hour, according to the local meteorological observatory of Fujian.