New Delhi, Dec 24 (PTI) Cold conditions persisted in the national capital as the minimum temperature remained below five degrees Celsius for the second consecutive day on Thursday, the India Meteorological Department (IMD) said.
The Safdarjung Observatory, which provides representative data for the city, recorded a minimum of 4.5 degrees Celsius, three notches below normal, and a maximum of 23.1 degrees Celsius.
Earlier in the day, 'dense' fog reduced visibility in parts of the city, affecting traffic movement.
“Dense fog in the Palam area reduced visibility to 100 metres between 5:30 am and 8 am. At Safdarjung, moderate fog lowered visibility to 201 metres,” Kuldeep Srivastava, the head of the IMD's regional forecasting centre said. According to the weather department, “very dense” fog is when visibility is between 0 and 50 metres, 51 and 200 is “dense”, 201 and 500 “moderate”, and 501 and 1,000 “shallow”. Cold wave conditions are likely in parts of Delhi over the next two days and the mercury is expected to drop to three Celsius on Friday.
“Moderate to dense” fog is also expected during the period, the IMD said.
For the plains, the IMD declares a cold wave when the minimum temperature is 10 degrees Celsius or below and is 4.5 notches less than normal.
High humidity, low wind speed and lowering temperatures kept Delhi's air quality in the 'severe' zone for the third day on the trot, according to weather department officials.
No major improvement is likely till December 26, Srivastava said. The city's 24-hour average air quality index (AQI) was 423. It was 433 on Wednesday and 418 on Tuesday.
Air pollution in the neighbouring cities of Faridabad (408), Ghaziabad (440), Greater Noida (448) and Noida (441) also remained in the “severe” zone.
An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'. PTI GVS RHL