Chandigarh, Dec. 20 -- As dense fog persisted in Chandigarh for the third consecutive day on Friday, the city's day temperature dropped below the 20degC mark for the first time this season, intensifying the winter chill.

According to the India Meteorological Department (IMD), visibility dropped sharply through the morning, falling from 250 metres at 5.30 am to just 120 metres by 8.30 am at the Sector 39 observatory - the lowest recorded this season.

However, like the previous two days, visibility improved by late morning to around 2,500 metres by 11.30 am, before dipping again to 1,800 metres in the afternoon.

As per IMD, a "dense fog" day is declared when visibility drops between 50 and 200 metres. Visibility below 50 metres is classi...