Why did Hanoi sink in a dense fog from morning to afternoon?

The phenomenon will last until the end of this week when the Northern Region receives a new wave of cold air with strong intensity.

From the morning of January 2, many roads and streets in the capital of Hanoi and some provinces in the North were sunk in a dense fog, making foresight to be limited. After noon to afternoon, many traffic participants still have to turn on their headlights to facilitate their travel. Although it will be reduced the next day but until January 5, this situation continues to repeat.

High humidity 70-85%

Mr. Le Thanh Hai, Deputy General Director of the National Center for Hydrometeorology, analyzed the cold season in Northern Vietnam lasting from 8 to 10 months, often falling in the fall, winter and spring. Besides, the cold season is divided into 2 distinct periods.

The first period includes October, November and December. It is sunny, causing a dry, cracked feeling. After that, the end of the cold season consists of January, February, March and early April, with cold and wet characteristics.

Standing at the foot of Keangnam building, on January 4, the highest floor could not be seen.(Photo: Le Hieu).

The cold air masses from Siberia high pressure (Russia) are blown down by two roads, causing different weather characteristics. With the first path, the air goes straight to the north of our country, the state is dry.

However, there is also another path, which is to the southeast of China, the cold air mass carries lots of water vapor, which changes the nature, makes it more moist and warmer.

The phenomenon of fog affects quite a lot of people 's lives, because the high humidity is about 70-85% causing prolonged and humid. Even, humidity in April 3-4 may reach 90%.

According to Mr. Hai, fog is an agent that makes vision limited, especially obstructing air activities.

"Many flights at Cat Bi airport, Vinh may have to cancel or relocate the schedule, due to inadequate safety conditions. Currently, the route visibility at Noi Bai airport is about 1 km, still ensuring the standard to take off and land , " he added.

Last until the end of the week

Mr. Le Thanh Hai said that fog, humidity will last until the end of this week and only end when the North will welcome a new wave of cold air with strong intensity on the night of January 7.

"The North will be cold and cold. The lowest temperature in the delta is about 10-15 degrees C, mountainous areas fluctuate 5-10 degrees C, and in the mountainous areas from 0 to 5 degrees C " Mr. Hai informed.

From the night of January 7, the North will welcome the cold, strong air, causing severe cold.(Photo: Hoang Ha).

People need to keep their bodies warm, because moist air can affect the respiratory tract, making them more susceptible to colds.

Fog obstructs traffic, people join road traffic, especially on highways, so pay close attention. Boats in the area near the shore should move slowly to avoid an unfortunate accident.