Pollution has combined with air stagnation across northern India and Pakistan to lead to extremely poor air quality during the past week. Without a significant change in the overall weather pattern, poor air quality and low visibility will remain into the start of the coming week.
Visibility from Islamabad, Pakistan to New Delhi and Patna, India has been reduced to less than a kilometer (0.6 of a mile) at times during the past several days due to the pollution. Visibility at New Delhi's Indira Gandhi International Airport has dropped to near zero on occasion since late late week.
Smog is so prevalent it had also been keeping daytime temperatures cooler across this region.
A pattern like this is fairly typical during this time of year in northern India due to the combination of air pollution and a ridge of high pressure sitting across the country leading to air stagnation.
Due to the poor visibility, the India Meteorological Department has issued dense fog warnings through Sunday in West Madhya Pradesh.
By Tuesday, an upper level disturbance moving across northern India could bring enough mixing to the atmosphere to help clear the air somewhat, but poor air quality will likely still be a problem.
In situations with poor air quality such as this, outdoor time should be limited and those with respiratory problems should avoid outdoor activities all together.