The southwest monsoon arrived in Delhi on Sunday, simultaneously covering the entire country nine days ahead of schedule—a rare meteorological convergence that has occurred only five times since 2001, when IMD onset records for the Capital began. Monsoon arrived in Delhi two days after the normal June 27 date, representing the 11th earliest arrival since IMD records began. (PTI)

Such timing has happened just four times previously—in 2003 (July 5), 2013 (June 16), 2018 (June 28), and 2021 (July 13).

This year’s June 29 convergence marks the earliest complete national coverage since 2020, with the monsoon typically taking a median of four days to cover the entire country after reaching Delhi during the 2001-2025 period.

“The Southwest Monsoon has further advanced into remaining parts of Rajasthan, West Uttar Pradesh and Haryana and entire Delhi today, the 29th June 2025. Thus, it covered the entire country on 29th June, 2025, against the normal date of 08th July (nine days before the normal date),” the IMD said in a statement on Sunday.

Data analysed by HT shows the monsoon’s travel patterns this year defied typical progression. While the seasonal rains arrived in Kerala on May 24—the fourth earliest since 2001—the 36-day journey from the southern coast to Delhi ranks as the sixth longest in the same period.

This year’s Delhi arrival came two days after the normal June 27 date, representing the 11th earliest arrival since IMD records began.

The arrival brought immediate relief from sweltering humidity, with Delhi’s maximum temperature settling at 32.8°C—five degrees below normal for this time of year. Dark grey clouds loomed over the city through the day, with temperatures forecast to similarly hover between 31-33°C on Monday. The minimum on Sunday was 26.8°C. The relative humidity was between 77% and 98%.

Sunday’s onset also ended a string of missed forecasts by the India Meteorological Department, which had repeatedly predicted the monsoon’s imminent arrival since June 24. The agency initially forecast arrival by June 24, then extended the timeline by 36 hours. On June 25, IMD predicted arrival within 24 hours, before adopting more general language about “favourable conditions” by June 26.

Rainfall distribution on Sunday across the capital varied significantly, with Safdarjung—Delhi’s base weather station—recording 5.1mm between 8.30am and 5.30pm. Palam logged the highest precipitation at 13.6mm, followed by Ayanagar (9.9mm), Rajghat (8.3mm), Lodhi Road (5.3mm), Pusa (1mm), and Najafgarh (2mm).

An IMD official confirmed the onset declaration met established criteria for the subdivision. “This included widespread light rain, which was seen in Chandigarh, west UP, Delhi and Haryana. We also had easterly winds. Delhi is part of the sub-division of Haryana-Chandigarh and Delhi,” the official explained.

The monsoon’s journey this year revealed complex timing patterns across different regions. The seasonal rains arrived in Kerala on May 24—eight days ahead of schedule and the fourth earliest since 2001. It then reached Mumbai on May 26, weeks ahead of the normal June 11 date, before experiencing a hiatus in early June and regaining momentum from June 16.

The sweep marks an important milestones for the rains that hold critical importance for India’s agricultural sector on which at least 700 million people depend for their livelihood. The seasonal rains account for 70% of India’s annual rainfall and prove crucial for yields of rice, wheat, sugarcane, and oilseeds in a country where farming employs over half the population while contributing about 15% to the economy.

The longest monsoon journey from Kerala to Delhi occurred in 2002, taking 51 days from May 29 to July 19. This year’s arrival in Delhi came two days after the normal date of June 27 and represents the 11th earliest arrival in the capital since 2001, when IMD onset records for Delhi began.

Analysis by Akshay Deoras, a research scientist at the National Centre for Atmospheric Science & Department of Meteorology at the University of Reading, shows that both the May 24 Kerala onset and June 29 national coverage rank ninth earliest since 1960. The 36-day gap between Kerala onset and complete national coverage ranks 32nd highest in the 66-year period from 1960 to 2025.

Last year, the monsoon covered the entire country six days ahead of schedule on July 2.

The IMD has issued a yellow alert for Delhi on Monday, forecasting light to moderate showers, with light rain likely to continue from July 1 through July 5. Heavy to very heavy rainfall is forecast across many parts of northwest, central, eastern, and northeastern India over the next seven days, with isolated extremely heavy spells expected over Jharkhand and Odisha on June 30.

Meteorologist Ashwary Tiwari, who runs the IndiaMetsky handle on social media, explained that a low-pressure area over the Bay of Bengal will enhance moisture flow by Monday. “The low pressure area will move over the axis and feed moisture, increasing its strength and depth. We can expect more rain over Delhi and other parts of northwest India on Monday,” he said.

IMD’s long-range forecast for northwest India projectsa normal monsoon [92-108% of the long-period average of 61.5cm] this season. The Long Period Average represents rainfall received in the region over the 50-year period between 1961 and 2010. Between June 1 and June 29, there was 8% excess rain over the country with 37% excess over northwest India; 24% excess over central India; 17% deficiency over east and northeast India and 2% deficiency over south peninsula.

With the monsoon now established across the entire subcontinent ahead of its usual mid-July timeline, the focus will be on whether adequate rainfall is sustained and evenly spread, especially through the crucial crop-growing months ahead.