Safdarjung and Pusa recorded wind gusts up to 72 kmph. These high-speed winds contributed significantly to the sudden cooling and dust movement across several parts of the city, said officials.A sudden thunderstorm, accompanied by lightning, rain and strong winds swept across parts of Delhi on Wednesday evening, bringing a sharp drop in temperatures after a hot day and gusts reaching up to 98 kmph, according to the India Meteorological Department (IMD). Several parts of the city also saw isolated hailstorm activity during the night.At Safdarjung, where the primary weather station is located, the temperature dropped by 10°C from 35°C to 25°C. On the other hand, Palam recorded a fall of 9°C, from 35°C to 26°C. At 11°C, Najafgarh saw the steepest drop as the temperature fell from 33°C to 22°C. Ayanagar recorded a decline of 10.1°C from 31.8°C to 21.7°C, and Narayana saw a fall of 9.1°C from 31°C to 21.9°C. Other areas also witnessed notable cooling, with Jafarpur recording an 8°C drop, Janakpuri 8.1°C, and Pusa 6.9°C. The fall was relatively lower in Pragati Maidan (5.2°C), Mayur Vihar (4.6°C), and Pitampura (2.2°C).Strong winds accompanied the storm. Palam recorded the highest wind speed at 98 kmph. Safdarjung and Pusa recorded wind gusts up to 72 kmph. These high-speed winds contributed significantly to the sudden cooling and dust movement across several parts of the city, said officials.The IMD had initially issued a yellow alert around 7 pm, forecasting light to moderate rainfall with gusty winds of 30-40 kmph across Delhi-NCR. Within half an hour, this was upgraded to an orange alert for moderate thunderstorms with wind speeds of 40-60 kmph. By around 8:10 pm, a red alert was sounded for parts of the city, warning of severe thunderstorm activity with wind speeds reaching up to 80 kmph in isolated pockets, particularly over West and Southwest Delhi, including areas such as Dwarka, Najafgarh and Palam.Rainfall, however, remained light and scattered despite the intensity of the storm. Safdarjung recorded negligible rainfall initially, with around 1.8 mm during the evening spell, while Palam recorded 0.1 mm cumulatively, increasing to about 2.0 mm later. Lodhi Road reported only trace rainfall, and Ridge recorded up to 0.2 mm. Pitampura and Mayur Vihar, Jafarpur recorded 0.5 mm of rain. Janakpuri recorded around 1 mm, whereas Pusa and Ayanagar recorded negligible rainfall.Earlier in the day, IMD had indicated that conditions were becoming favourable for the advance of the Southwest Monsoon over parts of the Andaman Sea around May 16, which is slightly ahead of the usual timeline and suggests an early onset phase for the monsoon system.At the same time, heatwave to severe heatwave conditions are expected to persist over Northwest and Central India during the week, with such short-duration thunderstorms likely to bring temporary relief, the IMD said in a statement.Story continues below this adIn its forecasts, IMD said there is a possibility of very light rain in the Capital during morning hours on Thursday. There is no alert issued by the agency for the coming days. However, a fresh Western disturbance could affect Northwest India from Friday, it said.