Vo Ta Tan, 50, collapsed in a field of the central province while harvesting peanuts with his wife. He later went into a deep coma, and was rushed to the hospital with no pulse, dry skin and a body temperature of 41 degrees Celsius.

Ha Tinh Province recorded the nation's highest ever temperature last month as the mercury hit 43.4 degrees Celsius.

"The patient died before reaching the hospital. Examination suggests that he died of a heat stroke. We tried to resuscitate him [...] to no avail," said Nguyen Ngoc Trai, head of the Emergency Department at the Loc Ha District General Hospital.

Trai also cautioned people to refrain from going out between 11 a.m. and 3:30 p.m. during hot days to prevent heat strokes. Full-body clothing and masks should be worn if one has to go out, he added.

Many places across Vietnam are experiencing a summer hotter than normal. Big cities like Hanoi and Saigon have been hit with extremely high levels of UV rays and sweltering temperatures.

The heat wave was the result of a developing low-pressure area from the west, according to the National Hydro-Meteorological Forecasting Center.

Weather experts have warned that Vietnam should brace for more heat waves set to sweep through the country this summer.

A study published in the journal Climatic Change last September said that Southeast Asian nations like the Philippines and Vietnam would be most affected by heat-related mortality, along with countries in Southern Europe and South America.