Light rains bring down temperature in Delhi amid severe heatwave; AQI improves

The IMD has forecast another spell of light rain and gusty winds across the city during the day on Thursday

A spell of gusty winds and isolated rain across Delhi since Wednesday night brought down the temperatures after days of severe heatwave, the India Meteorological Department (IMD).

Thursday’s drop in minimum temperatures also halted a streak of six consecutive warm nights in Delhi. (ANI file photo)

The development comes a day after Delhi recorded its warmest summer night in at least 55 years.

Due to an approaching western disturbance leading to sharp dip in temperature, gusty winds up to 52 km/hr were recorded across the national Capital, with light rainfall seen in some parts late on Wednesday and in the early hours of Thursday, with Safdarjung clocking a minimum temperature of 29.6°C – two degrees above normal.

The minimum was 35.2°C on Wednesday, making it the warmest night ever for Delhi across all months in the period 1969-2024, the IMD had said.

Putting that into perspective, the previous highest during this period was 34.9°C on May 23, 1972.

The IMD said the maximum wind speed of around 52 km/hr was recorded at three IMD automatic weather stations – Pitampura, Mayur Vihar and Ujwa.

At Pragati Maidan, the maximum wind speed was 50 km/hr, 46 km/hr at Jafarpur and 43 km/hr at south Delhi’s IGNOU.

“Palam had average wind speed of around 28 km/hr, which touched 48 km/hr between 11 pm and 11:30 pm on Wednesday night. This reduced visibility from 4,000 metres to 1,500 metres. There was also a sharp drop in temperature there, with it dipping by 7°C from 38°C at 11 pm to 31°C at 11:30 pm,” said an IMD official, stating it fell from 38°C at Safdarjung to 32.6°C during the same period.

“The last few nights have been extremely warm, as temperature has dropped fairly gradually and by sunrise, starts to rise again. This spell of gusty winds and isolated rain has provided a cooling effect to the region,” the official added.

Thursday’s drop in minimum temperatures also halted a streak of six consecutive warm nights in Delhi.

The IMD classifies it as a warm night when the maximum temperature is over 40°C and the minimum is 4.5 degrees or more above normal.

The minimum of 35.2°C on Wednesday was eight degrees above normal. Prior to that, the minimum was between 5 and 6 degrees above normal, recording lows of 33.8°C on June 18; 33.0°C on June 17; 33.2°C on June 16; 32.4°C on June 15 and 33.4°C on June 14. On June 13, it was 29.4°C.

IMD data at 8:30am on Thursday showed Lodhi road recorded ‘trace’ rainfall, but none of the other four manual observatories – Safdarjung, Ayanagar, Ridge and Palam recorded any rain.

The IMD has forecast another spell of light rain and gusty winds across the city during the day on Thursday, which should provide relief in terms of day-time temperature too, snapping a heatwave streak of 11 consecutive days now.

The IMD classifies it as a heatwave when the maximum is over 40°C and also 4.5 degrees or more above normal. The maximum was 43.6°C on Thursday, 4.8 degrees above normal. Forecasts show Delhi’s maximum could drop to 40°C on Thursday.

AQI improves

Delhi meanwhile also recorded some marginal improvement in its air quality, which dropped down to the ‘poor’ category from ‘very poor’.

Delhi’s average air quality index (AQI) was 214 (poor) at 9am on Thursday – down from 306 (very poor) at 4pm on Wednesday.