Cold wave: North India to see mercury drop, says IMD
A cold wave is expected to hit portions of northwest India in the coming days, according to the India Meteorological Department (IMD). The lowest temperature is expected to drop by two to four degrees Celsius over most of northwest and neighboring central India. The minimum temperature in most parts of east India and Maharashtra may decrease by two to three degrees Celsius.
Why does it matter?
- As per the forecast, this is the first cold wave of the season.
- When the minimum temperature is 10 degrees or 4.5 degrees to 6.4 degrees below the normal for that time of year, a cold wave is called at a weather station in the plains.
- It can also be declared if the minimum temperature is less than or equal to four degrees Celsius.
When and where is the cold wave expected to hit?
From December 17 to 21, a cold wave or severe cold wave might hit Punjab, Haryana, Chandigarh, Saurashtra, and Kutch. From December 18 to 21, a cold wave is expected in north Rajasthan, as per the IMD forecast. Western Uttar Pradesh is expected to see similar weather conditions from December 19 to 21, and Gujarat from December 19 to 20.
Severe fog expected during morning hours
On Friday and Saturday, dense to very dense fog is expected in isolated pockets across Punjab and Haryana in the morning hours. On Friday, it will pass over northwest Rajasthan, Assam, Meghalaya, Nagaland, Manipur, Mizoram, and Tripura. "Ground frost conditions in the morning hours in isolated pockets very likely over Saurashtra and Kutch, Punjab and Haryana during the next four days," the IMD said.
What is the scenario of cold wave in Delhi?
The IMD has not yet published a forecast for a cold wave in Delhi. In the last 11 years, there hasn't been a cold wave in Delhi before December 20, senior IMD scientist RK Jenamani told The Indian Express. In 2018, Delhi witnessed a cold wave for eight days in December. There were three such days in 2019 and six in 2020.
Cyclonic turbulence hung over India and its neighbors
On December 15, a cyclonic circulation was spotted over Jammu and its neighboring areas. Another western disturbance was seen over Afghanistan and the surrounding areas. There is a gap between both the western disturbances, said Jenamani. Strong westerly or northwesterly colder winds are predicted to impact northwest India during this time gap. Cold waves are most common from mid-December through the end of February.
What are western disturbances?
"Cold waves depend on weather systems from the middle latitude areas... Europe or West Asia... that bring cold winds to northwest India," said Jenamani. Storms that originate in the Mediterranean region and bring winter rains to northwest India are known as western disturbances.