A cold front is moving towards northern Vietnam and would begin affecting the area on Monday.
The National Hydro Meteorological Forecasting Center said that northern provinces would experience extremely cold on wide area.
In Hanoi, temperatures would fall to 17-20 degrees Celsius at daytime and 10-12 degrees at nighttime.
In mountainous regions, the mercury will tumble to just 7-10 degrees with Lao Cai and Son La provinces slate to suffer frost.
After blanketing the north, the cold front would head towards central and southern provinces.
Ho Chi Minh City weather will be affected with temperatures dropping to 20-22 degrees Celsius and fog appearing in early morning.