What smog-hit New Delhi and its neighbourhood could well do with is a blast of dry westerly winds or well-endowed 'western disturbances' (periodical low-pressure waves) which trigger seasonal showers.
While the dry winds would blow away the smog and its contents, the rain brought in by western disturbances could literally wash the air clean over the national Capital.
LIGHT WINDS, FOR NOW
Only, the stricken metropolis would need to wait until the next week for relief on either front. For now, the winds are light north-westerly and would stay as such for the next three days.
This doesn't help. Since North India is slipping into winter, the typical 'sinking motion' of air makes the air sit over ground with its baggage of seasonal pollutants.
This is quite unlike in summer when the sun heats up the environment, the air becomes warmer and lighter (lower pressure which aids cloud formation and rain), rises and spreads out.
So it is no wonder that the advent of winter climes worsens the air quality, made even worse by crop burning in Punjab and Haryana as farmers prepare their farms for the rabi crop.
Judging from the India Met Department's (IMD) projections, a 'well-endowed' western disturbance would arrive over North-West India precipitating winter-time rain next week.
THUNDERSHOWERS NEXT WEEK
Western disturbances originate from the Mediterranean, travel east across Iraq, Iran, Afghanistan and Pakistan before crossing the Rajasthan-Gujarat border into North-West India.
These disturbances are the main weather features responsible for setting the tone for winter weather over the country, ranging from being warm, wet or foggy to seasonal cold, chill or frost.
Warm western disturbances mean they carry moisture mopped up from the North Arabian Sea, which is precipitated as snow/ rain/ thundershowers over the hills and plains of North-West India.
A disturbance, 'endowed' in this manner, is expected to bring rain/thundershowers to Delhi and its neighbourhood next week, promising to clean up the atmosphere.
Seasonal rains/thundershowers are keenly awaited also by farmers of the region, who have prepared farms for the winter crop.