Ahead of Diwali, Delhi-NCR witnessed the season’s first fog with both the IGI and Safdarjung Airports reporting poor visibility with significant reduction to the range of 600-800 metres on Thursday between 7 a.m. and 11 a.m. Visibility during the same period on Wednesday was at range of 1,500-2,000 metres in mist/smog, according to IMD.
“This (fog spell) has been due to calm/light wind prevailed during this period and presence of higher humidity in the range of 88-95 per cent,” the IMD’s R.K. Jenamani said.
Such shallow to moderate fog likely to occur mainly in the morning hours till Saturday and reduce thereafter due to likely strengthening of the winds over the region from the same day noon/afternoon, he said.
In deep winters, fog season means less and less visibility and especially for airports, means diversion of flights.
On the highways, dense fog results in accidents, many of them resulting in fatalities.
Meanwhile, the Air Quality Index (AQI) in Delhi on Thursday will continue to remain under the ‘very poor’ category, settling at 339, with with PM2.5 being the predominant pollutant.
According to the Air Quality Early Warning System for Delhi, the AQI slipped to the ‘very poor’ category on Tuesday.
“The average wind speed is less than 10 kmph, and low wind speeds do not disperse pollutants. The air quality could begin improving from November 7 onwards with strong winds,” it added.
