Delhi Visibility Plummets to 50m, AQI Remains 'Very Poor

In the early hours of Thursday, Delhi experienced dense fog, causing visibility to plummet to a mere 50 meters. The India Meteorological Department (IMD) reported that this reduced visibility persisted for six hours between 12:30 am and 6:30 am, impacting both flight operations and train schedules.

The minimum temperature in Delhi rose by a degree at most locations, according to the IMD. Safdarjung, the representative of Delhi's weather, recorded a minimum temperature of 6.6°C on Thursday, just a degree below the normal range. Despite the slight increase in temperature, the dense fog lingered for nearly six hours, with forecasts indicating its continuation over the next two days.

The IMD classifies a 'cold wave' when the minimum temperature is 4.5°C or more below normal. During the preceding five days, Delhi experienced such cold wave conditions, with temperatures consistently below 4°C. However, a shift in wind patterns, with warm easterly winds blowing towards the national capital, has led to a rise in mercury by almost three degrees in the last 48 hours.

The impact of the dense fog was felt at the Delhi airport, where visibility oscillated between 50 and 100 meters during the critical hours of 12:30 am to 6:30 am. This resulted in delays for over 50 flights and the cancellation of at least five flights. Additionally, 18 trains to or from the capital faced delays exceeding one hour due to the challenging weather conditions.

Despite improvements in visibility later in the morning, dense fog persisted for a considerable period, causing disruptions in both air and rail travel. An official reported, "We saw dense fog for around six hours before visibility improved to around 350 meters by 8:30 am. This will improve further in the next two hours."

In terms of air quality, Delhi's average Air Quality Index (AQI) stood at 323 (very poor) at 9 am on Thursday, a slight improvement from the 368 (very poor) recorded at 4 pm on Wednesday. However, the air quality is expected to remain 'very poor' until January 20, according to forecasts by the air quality early warning system (EWS).

The EWS stated in its daily bulletin on Wednesday, "Delhi’s air quality is likely to be in the ‘very poor’ category from January 18 till 20. The outlook for the subsequent six days shows the air quality is likely to be between ‘very poor’ and ‘poor.’"