Why is the hot sun lasting in Vietnam?

According to meteorological experts in Vietnam, prolonged heatwaves are taking place, causing temperatures in some areas to exceed the highest level in history.

According to statistics from meteorological and hydrological centers across the country, the hottest is the North Central region with temperatures up to 43 degrees Celsius (previously, this local temperature was at the highest time also only reached 41 to 42 degrees C). Even the area with a cool climate like the Northwest has recorded a record temperature of 40 to 43 degrees Celsius.

In two big cities, Hanoi and Ho Chi Minh City, the temperature in the last one month has always remained at a high level but has not exceeded the record of previous years. Specifically, in Hanoi, the peak temperature is about 40 degrees, Ho Chi Minh City is 38 degrees (still lower than the level of 39.6 recorded in 1998). Although not exceeding the record, but the high temperature in recent days made people in Ho Chi Minh City and Hanoi face many difficulties in traveling and living.

In Hanoi and Ho Chi Minh City, the temperature for more than a month has always remained high.

According to weather forecast expert Le Thi Xuan Lan, former Deputy Head of Forecast Department, Hydrometeorological Station of the Southern region, the prolonged heat wave in this country is unusual compared to the same period of previous years. This year's sunny season comes too early in the North Central region, the temperature is also higher.

The temperature at many measurement points in the Southern region at this time is also higher than in previous years. The highest is So Sao station (Binh Duong), the measured temperature is 38.3 degrees C while last year was 38.1 degrees C.

The weather experts said that the cause of prolonged heat is because the western low pressure area is active in the areas of Myanmar, India, and Thailand and affects Vietnam .

In addition, the North Central region is also affected by the phantom effect so it is hotter, the humidity is low, making people feel hot and uncomfortable.

In meteorology, the phenomenon of wind passing the mountain is called foehn. From the side of the mountain to receive the wind, the air moves upward, the higher the air, the more cold it is, and the agglomeration creates clouds for the rain on the side of the wind, and the heat is increased by the condensation.

After crossing the mountain pass, the wind blew down this mountain. At that time, the air has become drier, the temperature has increased due to the air being compressed, so to the foot of this mountain side the air becomes hotter and hotter than the air on the side of the wind.

This phenomenon is called phlegm and hyperthermia, moisture effect is called a lisp effect. The stronger the effect, the more air the air reaches to the side, the more humid the wind and the higher the mountain peak. For example, with a high mountain range of 3,000 m, the air temperature across the mountain is 10 degrees Celsius, to the foot of this mountain side the temperature is up to 18 degrees Celsius - According to Xuan Hoa - National Hydrometeorological Center.

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