NEW DELHI: While North India grapples with higher temperatures and humid conditions, the Indian Meteorological Department (IMD) has officially announced the arrival of the Southwest Monsoon at the Kerala coast on June 4, three days later than its normal arrival date of June 1.
The expected date for the monsoon to reach Delhi is June 27, with the entire country typically covered by July 8.
In its bulletin, the IMD indicated that the Southwest Monsoon (SWM) has set in over Kerala and Mahe, parts of Karnataka and Tamil Nadu, the remaining regions of Comorin, the southeast Bay of Bengal, and additional areas of the Bay of Bengal as of June 4, 2026.
The IMD had originally forecasted the commencement of the Southwest Monsoon for May 26, with a model error margin of ±4 days. "In terms of our forecast, there is a five-day delay," said Dr.Mrutyunjay Mohapatra, Director General of Meteorology at the IMD. "The forecast was for May 26, with an error margin up to May 30. Consequently, the actual onset date over Kerala this year is delayed by five days from the forecast date," he explained.
In the previous two years, 2024 and 2025, the monsoon arrived earlier than the normal scheduled date of June 1.
The IMD predicts that this monsoon season (June to September) is likely to be below normal, with expected rainfall at 90% of the Long Period Average (LPA) of 870 mm. It is anticipated that rainfall will be normal (94-106%) over East and Northeast India, while the rest of the country will experience below-normal to deficient rainfall. Even the monsoon core zone, essential for rainfed agriculture, is projected to receive less than 94% of the LPA.Conversely, the South Peninsula and Central India are expected to receive less than 94% of the LPA, while the Northwest region may see rainfall below 92% of the LPA.
In 2023, the country experienced a deficient monsoon with total rainfall falling approximately 6% below average, impacting food production.
The IMD declares the onset of the monsoon once three main criteria are met: at least 2.5 mm of rainfall must be recorded at 60% of 14 designated weather stations spread across Kerala, Karnataka, and Lakshadweep for two consecutive days; clouds must exhibit Outgoing Long Wave Radiation (OLR) of less than 200 W/m²; and the depth and strength of the westerlies should be around 25-30 knots.
