In particular, the central coastal provinces are forecast to suffer an extreme heatwave at 35- 38 degrees Celsius, even above 39 degrees Celsius in some mountainous areas.
The return was due to strong operation of a low- hot pressure zone from the westwards in combination with the southwest monsoon causing foehn wind effect.
From May 18, temperatures across the regions remain between 36 degrees Celsius to 39 degrees Celsius while the maximum temperature in northwestern part of Northern region and mountainous area of the Central region could climb to over 40 degrees Celsius.
The heatwave is predicted to last till May 20.
Meanwhile, an average temperature as high as 32-35 degrees Celsius, showers and thunderstorms are forecast to see in the Southern region and Ho Chi Minh City.
