Weather stations across the capital recorded 38-40 degrees, a degree higher than on Sunday, the National Center for Hydro-Meteorological Forecasting said.

The mercury is expected to hover at 37-38 degrees until Friday before things cool down to around 32 degrees during the weekends and the first half of next week, according to U.S. forecast services provider AccuWeather.

Thirty four localities in northern and central Vietnam saw temperatures of 37-40 degrees on Monday.

In several places in Hoa Binh Province next to Hanoi and other neighboring provinces like Ha Nam and Hung Yen too the temperature climbed to 40 degrees, the center added.

Nguyen Van Huong, head of its climate forecasting division, said the searing heat is being caused by a low-pressure area from the west and the foehn wind, which keep temperatures consistently above 35 degrees Celsius for up to 19 hours a day.

The heat is expected to persist for the next three days, he added.