Every year the south-west monsoon arrives in stages, and it leaves the same way. As the season winds down, forecasters track a "withdrawal line" that moves from the north-west of the country towards the south and east over several weeks.
How do forecasters decide the monsoon is withdrawing?
They look for a combination of signs over a region: several days without rain, drier air in the lower atmosphere, and a change in wind pattern as high pressure settles in. Only when these signs hold together is a region declared free of the monsoon.
Does withdrawal mean no more rain?
No. Thunderstorms and short, heavy spells can still occur after withdrawal, especially in the evening. In the south, the north-east monsoon usually brings a second rainy season later in the year.
Frequently asked questions
Why does withdrawal matter to farmers?
It signals when to harvest rain-fed kharif crops and when soil moisture is right to sow the next crop. A late, wet withdrawal can damage standing crops that are ready for harvest.
Does it affect air quality?
Yes. Drier, calmer air after the rains lets dust and smoke linger near the ground, which is why air quality in many northern cities starts to slip in October.
Where can I see the latest status?
Weather agencies publish daily maps of the withdrawal line. Local news bulletins summarise them for each region.
For cities, the end of the season is a good time to clean drains before the next year, and to watch for stagnant water, which keeps mosquito-borne diseases going well into autumn. Read our dengue advice for simple steps at home.
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