When cold winds start blowing fast and there is a sudden sharp drop in temperature, then the condition of cold wave is created. According to the Meteorological Department, when the minimum temperature goes below 10 degrees by four-five degrees or reaches around four degrees, then it is called cold wave.

When the day temperature drops by 2 degrees or below and the minimum temperature falls by 6-7 degrees below normal, then the situation is considered serious. It is also called severe cold wave.

Due to prolonged dangerous cold, the body’s immunity system becomes weak. In this, problems like hypothermia, high demand of calories, damage to trees and plants and death of cattle start increasing.

Apart from this, when the temperature falls to 4 degrees or below, there are no clouds and there is a sharp drop in the maximum temperature, then the possibility of cold wave increases.

According to the Meteorological Department, cold wave is declared in the plains when the minimum temperature is less than 10 degrees and it is 4.5 to 6.4 degrees below the average temperature. A severe cold day is considered when the maximum temperature is 6.5 degrees below normal.

Apart from this, cold wave is declared in hilly areas when the temperature is zero degrees or below and the maximum temperature is 4.5 to 6.4 degrees below normal.

At present the temperature is continuously going down in Delhi, Uttar Pradesh, Haryana, Punjab and Rajasthan. Apart from this, the temperature is also falling rapidly in Noida, Ghaziabad, Gurugram and surrounding areas.