Delhiites woke up to a pleasant breezy morning with the mercury level dropping to around 37°C on Wednesday.
The day temperature, which had been hovering around 44.4°C till Monday, dropped by more than seven degrees after traces of rain and a thunderstorm hit the city on Tuesday night.
Met officials have predicted that the temperature is like to drop further to around 36°C by the weekend, as more such thunderstorms are likely over the next few days.
“While a western disturbance triggered the rain and thunderstorm on Tuesday, a cyclonic circulation over Delhi-NCR is likely to trigger more thunderstorms till the weekend,” said a senior official of the Regional Weather Forecast Department.
But even though the day temperature remained well below the climatic normal, the cloudy sky didn’t allow the land to radiate the heat at night. As a result, the night temperature was at least two degrees above normal.
“More than the rain, it was the thunderstorm that helped the mercury level to plummet. The city received traces (less than 0.1 mm) of rain,” the official said.
While the thunderstorm helped cool the air at high altitudes, convection currents allowed the colder air mass to come down to lower levels. This helped to bring down the temperature.
Usually May and June are the hottest months in Delhi, with day temperatures often shooting above 45°C.
“But such interim reliefs triggered by western disturbances and cyclonic circulations in the summer months help to keep the rising mercury level under check. Without such checks, the mercury would shoot up, resulting in heat waves,” the official said.
A few heat waves have already swept the city since April, when the day temperature started hovering above the 40°C mark.
Met officials have, however, warned that heat waves would return once the effect of the western disturbance and cyclonic circulation fade.