In less than 24 hours, we have seen one of the most dramatic rises in air pollution ever in the national capital region. Just yesterday, people in the Delhi region would have welcomed relatively clean air and a wind that seemed to disperse air pollution. But by 7 pm last night, the situation started to change a great deal and over the next several hours the levels of PM 2.5 particles that cause the most amount of harm to the lungs touched 800-900 in places that's over 30 times the safe limit. The weather office has warned of a dip in air quality in the coming days with the northwesterly winds likely to bring pollutants in Delhi's air from Punjab and Haryana, where farm fires are continuing though the numbers of such cases are seeing a gradual decline.