Delhi has been experiencing alarming levels of air pollution over the past six days and policy measures to mitigate the crisis have not yielded much in containing the situation, especially due to stubble burning in the nearby states of Punjab and Haryana.

With restrictions under stage 4 of the Graded Response Action Plan (GRAP) in place, and the odd-even curb on vehicular movement in the offing, a western disturbance (WD) seems to have also come to the city’s rescue, weather officials said.

The weather pattern, which is impacting the Western Himalayan region, has led to a southeasterly shift in the wind direction. This has also led to an increase in wind speed of around 5kmph from calm conditions (0 speed) around 6am on Tuesday morning. The minor increase in wind speed has led to a marginal reduction in air pollution levels over the National Capital Region.

“As forecast by us, the western disturbance has brought relief. This will stay on for a few days,” M Mohapatra, director general of the India Meteorological Department (IMD), said. The weather department said that a fresh western disturbance is likely to cause light/moderate rainfall/snowfall over the Western Himalayan Region till November 10 and over adjoining plains on November 9.

Delhi NCR may receive very light rain or drizzles during this period. The wind direction moved southeasterly on Monday and on Tuesday it varied between northwesterly and southeasterly. When the winds move in the southeasterly direction, the impact of stubble fires in Punjab and Haryana on northwest Delhi will not add to the existing pollution levels in the national capital.

The western disturbance over the Himalayan region and an induced cyclonic circulation has been identified over northwest Rajasthan. Under its influence, light to moderate isolated rainfall/snowfall is likely over Jammu-Kashmir-Ladakh-Gilgit-Baltistan-Muzaffarabad on November 7 and 8, and scattered to fairly widespread rainfall/snowfall is likely on November 9 and 10. Meanwhile, isolated to scattered rainfall is likely over Himachal Pradesh between November 8 and 10, and over Uttarakhand on November 9 and 10. Isolated light rainfall is very likely over Punjab, Haryana, Chandigarh and West Rajasthan on November 9.

“The conditions will improve further (in Delhi) from November 11 when the western disturbance moves away, and northwesterly winds pick up speed blowing at 15-20kmph. That will help pollutants disperse,” explained Mahesh Palawat, vice president of climate and meteorology, Skymet Weather.