Shawdesh Desk: Delhi recorded its coldest day of the season on Saturday as the minimum temperature plummeted to 2.4 degrees Celsius in the morning, the weather office said.

Dense fog enveloped the city reducing visibility and affecting air traffic and vehicular movement in the streets. Several trains were also hit by the fog.

The India Meteorological Department (IMD) said the Safdarjung Observatory, whose reading is considered the official marking for the city, recorded the minimum temperature at 2.4 degrees Celsius.
The observatories at Palam recorded the minimum temperature at 3.1 degrees Celsius, at Lodhi Road 1.7 degrees Celsius and at Aya Nagar 1.9 degrees Celsius.

Zero visibility was reported in Palam Observatory area, which neighbours the city airport, due to very dense fog.

Four flights have been diverted from Delhi airport, said an airport official. The official said the flights are operating at the airport under CAT III B conditions, which means that the runway visual range (RVR) is between 50 metre and 175 metre.

Delhi is going to experience cold wave and severe cold day conditions simultaneously till December 29, after which it could see a rise in day temperature, IMD has said.

A severe cold day is when the maximum temperature is 6.4 degrees Celsius lower than normal while cold wave conditions are recorded when the minimum or night temperature is below 4.5 degrees Celsius.

There can be a change in wind direction on Saturday to easterly, temporarily, but night temperatures will continue to fall.
The cold and increase in fog cover also pushed the air quality into the ‘severe’ zone from the ‘very poor’ category.

The air quality plunged to severe with the Air Quality Index (AQI) reading 407 at 7.30am, as against the overall AQI of 373, the previous day.

IMD scientists said air quality may deteriorate from December 28-29 due to an increase in fog cover and reduced wind speed.

However, it is likely to improve significantly on December 31 on account of a Western Disturbance, which will bring rainfall and hailstorm.

The minimum temperature at Safdarjung Observatory was 2.4 degrees Celsius on December 30, 2013, and 2.3 degrees Celsius on December 11, 1996. The all-time record of low is zero degrees on December 27 in 1930.

The weather department had said on Thursday that Delhi-NCR is expected to record its second-coldest December since 1901 with chilling cold continuing to sweep the region.

“The mean maximum temperature for December was less than 20 degrees Celsius only in 1919, 1929, 1961 and 1997,” an IMD official said.

In December this year, the mean maximum temperature (MMT) till Thursday was 19.85 degrees Celsius. It is expected to dip to 19.15 degrees Celsius by December 31, he said.

Most parts of the city have witnessed 13 consecutive “cold days” or a 13-day “cold spell” since December 14. The last time such a long cold spell was witnessed was in December 1997.

After 1992, Delhi has had cold spells only in four years – 1997, 1998, 2003 and 2014.