The temperature could drop to 17-20 degrees Celsius, and 14- 17 degrees Celsius in mountainous areas.
Meanwhile, the South- Central and Southern regions including Ho Chi Minh City have experienced long-lasting extreme hot and sticky days with the highest temperature reaching 35 degrees Celsius.
The weather agency also issued a high tide warning on the Cuu Long (Mekong) river and Sai Gon river on Friday.
Accordingly, the water level on the Sai Gon river at Phu An station could exeed alert level 3.
Serious flooding following the high tide is warned to hit low- lying areas of Ho Chi Minh City.