Asia's monsoon season has officially commenced, bringing crucial rainfall to regions like India and Thailand. While early rainfall has been intense in some areas, the season is forecast to be below average overall due to developing El Niño conditions.
The monsoon season is critical for agriculture and water resources across Asia. Below-average rainfall could impact crop yields, food security, and water availability for millions.
The monsoon season has officially begun in parts of Asia, bringing essential rainfall that is vital for the region's economy. The south-west monsoon is triggered by a growing temperature difference between the Asian land mass and the Indian Ocean, drawing moisture-laden air inland.
On June 4, India declared the official onset of its monsoon season in the southern state of Kerala, three days later than its average start date. Since then, the system has advanced north-east into Karnataka and Andhra Pradesh. Stations in Kerala recorded up to 280mm (11 inches) of rain in just 72 hours between June 4 and 7, an amount equivalent to about half of London's average annual rainfall. Forecasts indicate an additional 200-250mm for the region this week, with surrounding areas under red warnings for heavy rainfall, flash flooding, and landslides.
The declaration of the monsoon onset is crucial for agriculture in India, particularly for farmers of rain-fed crops like rice and cotton, enabling them to plant with confidence that prolonged dry spells have ended. Farther east, Thailand's monsoon season began on May 15. Local areas in the southwest have recorded up to 1,000mm of rain, with a further 300mm possible within the next week. The Thai meteorological department has cautioned that strong monsoon winds over the Andaman Sea could generate waves of 2–3 meters, advising small vessels to stay ashore.
Despite the intensity of the early rainfall, the overall forecast for the season suggests it will be below normal. The Indian meteorological department projects rainfall totals between June and September to be approximately 90% of the long-period average, partly attributed to the expected development and strengthening of El Niño conditions as the season progresses.