Moisture-laden winds check sudden rise in temp in Delhi, IMD pushes heatwave alert to Friday

A heatwave is now likely on Friday, when the maximum temperature could rise to around 42°C at Safdarjung and over 44°C in some parts of Delhi, the India Meteorological Department has predicted.

Cyclone Asani in the Bay of Bengal cooled temperatures in the capital with moist easterly and south-easterly winds, and delayed a heatwave across northern India that was expected from Tuesday.

A slum kid cools off on a hot day at a public tap. ((Anil Kumar Maurya/HT file photo))

A heatwave is now likely on Friday, when the maximum temperature could rise to around 42°C at Safdarjung and over 44°C in some parts of Delhi, the India Meteorological Department has predicted.

Safdarjung, Delhi’s base weather station, recorded a maximum temperature of 39.5°C on Tuesday, which is around normal for this time of the year, and 0.5°C lower than Monday’s maximum. It was 40.4°C on Sunday. Delhi saw a low of 28°C, three notches above normal.

The capital’s hottest location was Najafgarh, which recorded a maximum of 40.9°C, even as most parts of Delhi recorded a maximum temperature below 40°C.

Although a yellow alert has been sounded from Friday onwards, heatwave conditions are expected only in isolated parts of Delhi, IMD scientist RK Jenamani said. “The impact of Cyclone Asani will reduce from Wednesday night onwards, and after that, we will see the impact of a western disturbance from Friday, so a sharp rise in mercury is not expected at the moment,” he said.

A yellow alert warns the public regarding a weather phenomenon, while a green alert is for days where no significant weather phenomenon is expected. Currently, Delhi has a green alert till Thursday, and a yellow alert from Friday to Sunday.

A heatwave is declared when the maximum temperature is 40°C or higher, and also 4.5°C above normal.

For May 11-15, the normal temperature is 39.3°C, so the temperature at a station has to touch 43.9°C or higher on a particular day for it to be recognised as a heatwave, met officials said.

Forecast for Wednesday shows the maximum temperature will remain around 40°C and the minimum will hover around 28°C.