Chilly Thursday in Delhi, respite likely from Sunday

Minimum temperature was 6.4 degrees Celsius, a notch below normal. Maximum temperature was 21.3 degrees Celsius.

Thursday was a chilly day in the Capital with minimum temperature settling at 6.4 degrees Celsius, a notch below normal, with early morning fog disrupted rail services.

Students going to school bundled up in warm clothes in New Delhi. (Raj K Raj/HT File)

It was bright and sunny the rest of the day and maximum temperature was 21.3 degrees Celsius, a notch above the normal, a Met department official said.

“From Sunday, the maximum temperature is expected to rise a bit. However, winter is far from over in the city,” said a senior Met official.

While the city has been experiencing chilly winds from north over the past three days, the wind direction has now changed with warmer breeze coming from Punjab, Haryana, he said.

In the morning, fog delayed 35 Delhi-bound trains. Twenty three were rescheduled, according to a senior railway official.

Visibility at 5.30am at Safdarjung was 1,200 metres. It dropped to 600 metres at 8.30am, and later improved to 1,500 metres.

At Palam, visibility was 600 metres at 5.30am. Three hours later, it dropped to below 50 metres. It improved to 1,000 metres at 11.30am, the official said.

Humidity oscillated between 100% and 55%.

The weatherman has forecast partly cloudy skies for Friday with the likelihood of shallow to moderate fog in the morning. “Maximum and minimum temperatures are likely to hover around 20 degrees Celsius and 6 degrees Celsius, respectively, tomorrow.”

On Wednesday, maximum and minimum temperatures were 19.1 degrees Celsius and 4.2 degrees Celsius, respectively.

Air to be slightly more polluted today

Finer PM2.5 particles in the air, more harmful than PM10, will go up slightly to “very poor” level on Friday, according to the weather forecast.

Forecasts say it will deteriorate to 126 μg/m3. At this level, the response system calls for measures such as hiking parking fees by up to 4%, banning diesel generator sets and increasing the frequency of Metro trains. Pollution advisory says people with existing heart or lung diseases must avoid exertion.

On Thursday, air quality oscillated between “moderate” and “very poor” levels.

The Air Quality Index on Thursday was 300, which falls in the “very poor” category. The 24-hour rolling average of PM10 and PM2.5, however, clocked 215 μg/m3 and 120 μg/m3, according to the ministry of earth science’s System of Air Quality and Weather Forecasting and Research (SAFAR). These fall under “moderate” and “poor” categories. The permissible levels of PM10 and PM2.5 are 100 μg/m3 and 60 μg/m3, respectively.

Over the past few days, air quality has hovered between “moderate” and “very poor” levels, though it turned “severe” for one day.