Delhi: Mercury at 42.2°C, heatwave back in some areas as rain plays truant

The city recorded a maximum temperature of 42.2 degrees Celsius, two degrees above normal, and above Tuesday’s 39.6°C, when the Capital beat a 12-day long heatwave streak

The Capital sweltered once again on Wednesday, with a heatwave taking grip in some parts of the city, despite the weather office’s predictions of a cloudy sky and light showers a day ago.

Weather experts said thunderstorm activity remained confined to parts of Uttar Pradesh such as Mathura, Hathras and Aligarh.

The city recorded a maximum temperature of 42.2 degrees Celsius, two degrees above normal, and above Tuesday’s 39.6°C, when the Capital beat a 12-day long heatwave streak.

Four of the city’s 11 weather stations recorded a heatwave, which the India Meteorological Department defines as a condition of air temperature where the maximum temperature in the plains touch 40°C, and the departure from the normal temperature is between 4.5 degrees and 6.4 degrees. For a severe heatwave, the departure has to be above 6.4 degrees.

Mungeshpur, on Delhi’s northwestern border with Haryana, was the hottest spot in the Capital once again, with the maximum temperature jumping to 45.1°C.

Weather experts said thunderstorm activity remained confined to parts of Uttar Pradesh such as Mathura, Hathras and Aligarh.

A trough persisting over this region is likely to move down towards Delhi, they said.

“A fresh western disturbance, an induced cyclonic circulation over Punjab and moisture-laden easterly winds will provide relief from the heat from Thursday,” said Mahesh Palawat, vice-president (climate change and meteorology), Skymet Weather.

He said pre-monsoon activity in tropical and sub-tropical regions is a sudden development due to high temperatures and humidity and a micro prediction of such development is difficult.

Such events are not associated with a pre-defined or prominent weather system such as a low-pressure area or a depression that could help weather forecasters predict the area of impact with good probability, he said.

The weather office issued a yellow alert, warning of thundershowers and gusty winds around afternoon or evening in the Capital on Wednesday. However, the city recorded no such activity on Wednesday.

On Tuesday, a cloud cover had cocooned Delhi, causing the maximum temperature at the Safdarjung observatory — Delhi’s base weather station — to drop below 40°C for the first time this month.

IMD said consecutive western disturbances and lower-level easterlies predicted in the coming days are likely to keep the heat at bay.

It has issued a yellow alert, warning of thundershowers or light rain over the next five days. The mercury is predicted to drop to 34°C by Monday, IMD said.

The weather will become clear after June 21 and dry westerly winds will commence but a steep rise in temperature is not predicted, the department said.

The monsoon is expected to arrive in Delhi around the usual date -- June 27 -- or a day or two in advance, they added.

Last year, IMD forecast that the monsoon would arrive in Delhi nearly two weeks before its usual date. However, it reached only on July 13, making it the most delayed in 19 years.

The Capital has recorded a maximum temperature of 42°C and above on 27 days so far this summer season, the highest number of such days since 2012, according to data from the weather office.

In 2012, the city recorded a maximum temperature of 42 degrees Celsius or above on 30 days. The number of such days was 35 in 2010, the highest in the 1951-2022 period, the data showed.