According to the National Centre for Hydro-Meteorological Forecasting, most of northern Vietnam, except Dien Bien and Lai Chau, will experience hot to extremely hot weather on August 13.
Temperatures will generally range from 35-37 degrees Celsius, with some areas exceeding 37 degrees. Minimum relative humidity will fall to 55-60 per cent, while the hottest period will last from 11 am to 5 pm.
Hot weather will continue across much of the north on August 14, except in Dien Bien, Lai Chau, Son La, Quang Ninh and Haiphong. Temperatures are forecast at 35-36 degrees Celsius, with some places above 36 degrees, and minimum humidity of 60-65 per cent. The hottest period will be from 11 am to 4 pm.
From August 15, the widespread heatwave is expected to end in northern Vietnam and gradually ease in the central region.
The weather agency warned that prolonged heat could cause dehydration and exhaustion, particularly among people working or travelling outdoors for extended periods.