Monsoon hits Kerala 8 days early, earliest onset in 16 years, red alert issued: IMD

The monsoon has arrived in Kerala today, eight days ahead of its usual onset date of June 1, according to the India Meteorological Department (IMD). This marks the earliest arrival over the Indian mainland since 2009 when monsoon rains began on May 23. Historically, the usual onset date for the monsoon over Kerala is June 1. However, in recent years, there has been variability in these dates.

The IMD has noted heavy rainfall across several parts of Kerala as a result of a low-pressure area combined with the advancing monsoon system. This early onset is significant given the varied dates of arrival in past years, with the earliest recorded on May 11, 1918, and the latest on June 18, 1972. Over the past 25 years, the most delayed onset occurred in 2016 when it began on June 9.

The IMD has issued a red alert for several districts in Kerala, forecasting significant rainfall exceeding 204.4 mm within 24 hours. Districts such as Kannur and Kasaragod are under alert on May 24, with Malappuram, Kozhikode, Wayanad, Kannur, and Kasaragod following on May 25. An orange alert has been issued for Thrissur, Malappuram, Kozhikode, Wayanad, Kannur, and Kasaragod on May 23, indicating the potential for heavy rainfall and thunderstorms.

In addition to Kerala, Tamil Nadu, Telangana, and Andhra Pradesh are also expected to experience scattered showers and thunderstorms over the next five days, as indicated by the weather department. The monsoon is projected to move eastwards, crossing the south Konkan coast between Ratnagiri and Dapoli as a depression, further intensifying rainfall in the region.

The IMD follows specific criteria to declare the monsoon's onset, involving rainfall measurements at 14 key stations, wind patterns, and cloudiness. If more than 60% of these stations report rainfall of 2.5 mm or more for two consecutive days, with favourable wind patterns and low Outgoing Longwave Radiation, the onset is declared on the second day. This year's early arrival aligns with these criteria, reflecting the dynamic nature of India's monsoon system.