As of 11 p.m. it lay centered above the coast between Phu Yen and Khanh Hoa provinces with maximum winds of 60 kph, the National Center for Hydro - Meteorological Forecasting said.

It then moved west at 10-15 kph, and is expected to reach the Central Highlands on Monday morning bringing heavy rains to the area from Thua Thien-Hue to Binh Thuan provinces and the Central Highlands, it added.

In Phu Yen, the storm felled several trees in Tuy Hoa Town. Almost 60,000 houses experienced a blackout. Authorities were on standby for Sunday night, Vo Ngoc Kha, chairman of the Tuy Hoa people’s committee, said.

Khanh Hoa's Van Ninh District experienced rough seas with waves rising to 5-6 meters. Two people, Bui Van Het, 41, and Tran Huu Son, 33, were rescued by district authorities Sunday afternoon after they were trapped in their vessels in Van Phong Port.

Heavy rain and strong winds also caused blackouts in Ninh Tan Commune in Ninh Hoa Town. Power is expected to be restored by Monday morning, authorities said.

There were blackouts in Nha Trang too.

Central Vietnam, home to popular tourist destinations like Nha Trang and Quy Nhon, was hit by storm Matmo last month. It felled hundreds of trees, damaged many houses and caused widespread flooding in Phu Yen, Binh Dinh and Quang Ngai provinces.

Vietnam is hit by up to 10 tropical storms during the southwest monsoon between July and October. There were nine last year.