Orange alert for fog; road, rail, air traffic to be affected in Delhi
Hindustan TimesThe India Meteorological Department has issued an orange alert for “dense” to “very dense” fog in Delhi on Monday, predicting that visibility may drop to as low as 200m in most of the Capital and the surrounding region, affecting road, rail, and air traffic. IMD defines “shallow” fog in a region when visibility drops to 500-1,000m, “moderate” fog when visibility is 200-500m, “dense” fog when visibility is 50-200m, and “very dense” when visibility dips to 50m or lower. However, flights cannot take-offs if the visibility is less than 125 metres, and so, “dense” or “very dense” fog can lead to long delays at IGI. For example, Delhi on November 13 recorded the season’s first “very dense” fog, and the flight tracking website Flightradar24 said that more than 550 flights were delayed that day.