When will the monsoon arrive in Kerala? IMD predicts early onset this year; details here

The onset of the southwest monsoon over the Indian mainland begins with its arrival in Kerala, signalling a shift from the hot, dry season to the rainy season. It typically arrives around June 1, with a margin of ±7 days, and brings much-needed relief from the intense summer heat as it moves northward.

Monsoon onset in Kerala

According to an official release by the India Meteorological Department, the southwest monsoon is expected to arrive in Kerala on May 27 this year, slightly earlier than the typical onset date of June 1st.

Also Read: Weather Today: Monsoon to arrive early in Mumbai? IMD's yellow, orange alert for heavy rainfall in THESE areas today

If the monsoon arrives as forecast, it would be the earliest onset over the Indian mainland since 2009, when it arrived on May 23, according to IMD data.

Monsoon arrival trends in the last five years

Over the past five years, the monsoon has arrived early on two occasions—2022 and 2024. In both years, the monsoon onset occurred on May 29 and May 30, respectively, according to IMD data.

In 2024, the southwest monsoon brought rainfall at a four-year high, with about 108% of the long-period average (LPA), totalling 934.8 mm, compared to the LPA of 868.6 mm. The IMD had forecast above-normal rainfall for the season, predicting 106% of the LPA.

Also Read: What a normal monsoon means for Indian stock market? Experts list 8 stocks to ride the monsoon theme

For 2025, the IMD predicted that the southwest monsoon rainfall (from June to September) will likely be above normal, exceeding 104% of the Long Period Average for the country.

Southwest monsoon further advanced: IMD

Meanwhile, the Southwest Monsoon has further advanced over some more parts of south Arabian Sea, Maldives and Comorin area, the South Bay of Bengal, remaining parts of Andaman Islands and some parts of eastcentral Bay of Bengal.

According to IMD, conditions are favourable for further advance of the Southwest Monsoon over some more parts of south Arabian Sea, Maldives & Comorin area, South Bay of Bengal, central Bay of Bengal, and some parts of northeast Bay of Bengal during next three-four days.

The southwest monsoon typically begins to retreat from northwest India around September 17 and completely withdraws by October 15.

Also Read: Southwest monsoon rolls into Andaman and Nicobar region, two days in advance

In its April forecast, the IMD predicted above-normal cumulative rainfall for the 2025 monsoon season, dismissing concerns about the potential impact of El Niño, which is generally linked to reduced rainfall in the Indian subcontinent.

The monsoon is vital for India’s agricultural sector, which sustains the livelihoods of approximately 42% of the population and contributes around 18% to the nation’s GDP.

Also Read: Mint Primer | A good monsoon will be great for India. Here’s why

Additionally, monsoon plays a critical role in replenishing reservoirs, which are essential for drinking water and power generation across the country.

(With inputs from agencies)