An approaching western disturbance is likely to kill the early morning chill that Delhi had been experiencing over the past few days.

While the nights are expected to get warmer by at least five degrees, the day time temperature is expected to drop
equally over the next three days, officials at the India Meteorological Department (IMD) said on Saturday.

“We are also expecting some rain on January 22 (Tuesday) in Delhi. A western disturbance is approaching and it is likely to form an induced cyclonic circulation over NCR. This is going to trigger rainfall not just in Delhi but across the plains of northwest India,” said Kuldeep Srivastava, head of the regional weather forecasting centre in New Delhi.

On Saturday, the night temperature was 5.7 degrees Celsius, which is one degree below normal.

The day temperature shot up to 25.6 degrees Celsius, which was at least six degrees above normal.

Earlier this week, the night temperature had dropped to 4.2 degrees Celsius resulting in near cold wave conditions.

The IMD has, however, forecast that the night temperature is expected to shoot up to 11 degrees Celsius by January 22.

The day temperature will, however, drop to less than 20 degrees at the same time.

“When the sky remains clear, the day temperature shoots up and the night temperature drops. The opposite happens when clouds come in. The induced cyclonic circulation which is expected to form when the western disturbance approaches closer will help to form clouds,” said Srivastava,

Even though the IMD had forecast that winter would be warmer than normal this time, Delhi encountered the coldest December in 13 years this time.

In January, however, the nights have been warmer than December.

The air quality in the national capital, however, continued to remain in the ‘very poor’ category.

While the air quality index (AqI) was 397 on Friday, it improved marginally on Saturday and stood at 378.

“The AQI is expected to remain in the very poor zone over the next three days. The improvement would be marginal. It is because even though strong winds, which are favourable for dispersal of pollutants, would be blowing, the high moisture content in the air, because of the approaching western disturbance, will help trap pollutants,” said a scientist from Safar, the pollution forecasting wing of the Union government.

First Published: Jan 19, 2019 23:41 IST