New Delhi, Dec 13 (IANS): Heavy rain and thunderstorm in Delhi-National Capital Region (NCR) brought down temperatures to 17 degree Celsius on Thursday.

The change in weather has also brought with it respite for the locals of Delhi-NCR, as the Air Quality Index (AQI) is expected to come down from 'severe' to 'very poor' category.

Under the influence of a western disturbance, the national capital witnessed rain and strong winds for nearly two hours on Thursday evening.

"Widespread rainfall with isolated heavy rainfall/snow accompanied with thunderstorm/hailstorm is very likely over Western Himalayan region during the next 48 hours," a weather bulletin on IMD's website said.

"Fairly widespread to widespread rains with isolated heavy rainfall accompanied with thunderstorm/hailstorm is also very likely over Punjab, Haryana, Chandigarh, Delhi and West Uttar Pradesh during the same period," the bulletin added.

The Met department maintained that the national capital might witness heavy rains and thunderstorms on Friday as well.

Strong winds and rain, however, brought respite for the locals as the Met department is predicting that the change in climate might result in bringing down the pollution level.

As per the website of Air Quality Early Warning System for Delhi, the air quality is likely to improve significantly from 'severe' to lower end of 'very poor' category, owing to the rain and strong winds.

"The air quality is likely to improve further on Friday to moderate category," it said.

Earlier in the day, the national capital's air quality turned to the 'severe' category, with the overall AQI at 407.