At 4 am on August 24, the storm's centre was about 140 km east-southeast of Quang Ninh and 145 km east of Haiphong, according to the National Centre for Hydro-Meteorological Forecasting.
The storm was moving southeast at around 3 kph after remaining almost stationary for three to six hours. Winds near its centre reached 75-88 kph, with gusts of up to 103-117 kph.
By 4 am on August 25, Narra is forecast to remain over the eastern Gulf of Tonkin, about 110 km east of Bach Long Vi, before gradually turning east.
The storm is expected to weaken while moving northeast and later become a tropical depression before weakening further into a low-pressure area over southern Guangxi, China.
Strong winds have been recorded across coastal areas, including Bach Long Vi, Co To, Mong Cai, Uong Bi and Haiphong. The Gulf of Tonkin is forecast to see waves of 3-5 metres and very rough seas.
Authorities warned that severe weather could damage or sink fishing, cargo and tourist vessels, while also threatening aquaculture facilities, moorings and coastal infrastructure. Maritime transport, fishing and tourism could be disrupted.
Coastal areas of Quang Ninh and Haiphong could see strong winds capable of damaging temporary structures, trees, billboards and power infrastructure.
Northeastern Vietnam and Thanh Hoa recorded widespread rainfall of 100-200 mm between 7 pm on August 21 and 4 am on August 24. Lang Son, Quang Ninh, Bac Ninh and Haiphong received 180-380 mm, with some areas exceeding 400 mm.
Hong Ha in Quang Ninh recorded 547 mm, Mau Son in Lang Son 520 mm and Cat Ba in Haiphong 413 mm.
Northeastern Vietnam, southern Phu Tho, Thanh Hoa and Nghe An are forecast to receive another 20-50 mm of rain on August 24, with more than 120 mm possible in some areas. Haiphong, Hung Yen, Ninh Binh and Thanh Hoa could receive 40-100 mm, locally exceeding 200 mm.
Further rain is forecast across northern coastal and delta areas, Thanh Hoa and Nghe An from the night of August 24 into the morning of August 25.
Forecasters warned of urban and low-lying flooding, rising rivers and streams, flash floods and landslides in mountainous areas.
