Brace for a severe heatwave this week: IMD

The national capital will likely experience heatwaves from April 6, according to the India Meteorological Department.

A cooling breeze over Delhi may have provided some temporary relief to residents on Friday, but the national capital will likely experience heatwaves, or severe heatwaves, again from April 6, the India Meteorological Department (IMD) predicted on Sunday.

Delhi recorded a high of 39.4°C on Sunday. (Amal KS/HT)

Safdarjung, Delhi’s base station for weather, recorded a high of 39.4 degrees Celsius on Sunday, six degrees above normal. The mercury might cross 40°C at Safdarjung on Wednesday, and touch 41°C by Friday, the weather bureau said, issuing a four-day yellow alert from April 6 to 9.

While the maximum temperature was 39.4°C on Saturday as well, it had dropped to 36.5°C on Friday after strong winds blew across the capital. A similar spell of relatively strong winds is expected on Monday and Tuesday, before temperatures spike from Wednesday, met officials said.

“We saw wind speeds touch 30km per hour on Friday, resulting in a drop in mercury by 2-3 degrees. In the absence of strong winds, temperatures are likely to return around the 40-degree mark,” weather scientist RK Jenamani said.

“By Wednesday, Delhi will once again see calm conditions and clear skies, leading to mercury touching or cross the 40-degree mark in most places.”

“No rain is expected in the first and second weeks of April,” the IMD expert said. ”Therefore, temperatures are expected to rebound and heatwave to severe heatwave conditions will return.”

On Sunday, at least five stations in Delhi recorded a maximum that was above 40 degrees, meaning these parts witnessed heatwaves. These stations included Palam (40.2°C), Ayanagar (40.6°C), Ridge (41.4°C), Najafgarh (41°C) and Pitampura (41°C).

The IMD issues a ‘yellow alert’ to generally warn the public of a weather event that is likely to occur, while a heatwave is when the maximum is 4.5 degrees or higher above the normal mark.

It is also classified as a ‘severe heatwave’ if it is 6.5 degrees or more above the normal, but it can only be declared if the maximum is 40 degrees or higher as well.

At Safdarjung, the hottest day of the season so far has been on March 30, when the mercury touched 39.6°C. This was the city’s second hottest March day ever after last year, when it touched 40.1°C on March 30, according to Met department data from 1951 to 2022.

While Safdarjung is yet to touch 40°C, the highest maximum across all of Delhi so far has been 42°C, recorded at Narela on March 28.

Heatwave to keep grip on northwest India

The heatwave spell is likely to continue over parts of northwest India for the next five days and over Gujarat and Madhya Pradesh for the next three, the weather office warned.

“For now, it seems like the heat spell will continue and may intensify further. Wind speeds had picked up in the past two days and brought a minor respite. But now, winds are very slow again and are blowing from the westerly direction, which are very hot and dry areas. There is no weather system that can break this heat spell till at least April 11 or 12. A low pressure area is likely to develop over Bay of Bengal that may intensify into a cyclone. If the cyclone moves towards Andhra Pradesh and Odisha coasts, as the tracks are presently showing, there may be some moisture incursion from Bay of Bengal towards central and north India after it moves away. That moisture may trigger some pre-monsoon rains but that is not certain now. There is no active western disturbance affecting the Western Himalayas either. Normally, till end-March, western disturbances bring rain and snow to the higher reaches. But that did not happen this year,” explained Mahesh Palawat, vice president, climate change and meteorology, Skymet Weather.