Monsoon bids Delhi goodbye early, withdraws on September 23 for first time since 2002

The Southwest Monsoon has withdrawn from Delhi on Wednesday, September 23, marking its earliest retreat from the national capital since 2002, when the withdrawal was recorded on September 20, according to the India Meteorological Department (IMD).

The monsoon has also pulled back from most parts of Punjab, Haryana and Rajasthan, besides parts of Uttar Pradesh and Gujarat. The withdrawal line currently extends through Gurdaspur, Chandigarh, Muzaffarnagar, Aligarh, Dholpur, Udaipur, Deesa and Naliya, among other areas.

Drier weather expected across Delhi

With the monsoon moving away, Delhi and other parts of northwestern India are likely to gradually see drier weather.

The withdrawal, however, does not mean that rain will stop immediately across the region. Local weather systems can still bring isolated showers even after the monsoon has retreated.

The IMD determines withdrawal based on a combination of conditions, including a sustained reduction in rainfall, lower moisture levels and the development of an anticyclone in the lower atmosphere. A continued spell of dry weather and a clear, connected pattern of retreat are considered for further withdrawal.

As per the IMD's revised normal dates, the monsoon normally begins retreating from northwest India around September 17. It generally withdraws from most parts of the country by around October 15, although the southern peninsula usually sees a later retreat.

Delhi has seen wide variation in withdrawal dates

The date of monsoon withdrawal from Delhi has differed significantly over the years.

While the retreat was recorded on September 20 in 2002, the monsoon has stayed over the capital much longer in some years. In 2013, withdrawal was recorded on October 17, while it took place on October 8 in 2016 and October 2 in 2024.

The IMD's September 23 forecast showed no weather warning for Delhi between September 23 and 29.

Air quality starts to worsen

The monsoon's retreat comes as Delhi's air quality has begun deteriorating. The city's 24-hour average AQI rose from 118 on September 19 to 160 on September 20, 169 on September 21 and 178 on September 22, according to the Delhi Pollution Control Committee.

The AQI stood at 151 on Wednesday morning. Delhi's air pollution generally becomes a bigger concern from October, with conditions often worsening through November and December.