
Patna: The southwest monsoon is expected to arrive in Kerala on May 27, nearly five days ahead of its usual onset date of June 1, according to the Indian Meteorological Department (IMD). If the forecast holds, this would mark the earliest monsoon onset over the Indian mainland since 2009, when it reached Kerala on May 23.
This premature arrival has raised expectations of an early monsoon in Bihar as well, with the IMD estimating its likely onset in the state between June 13 and 15. In 2023, the monsoon reached Bihar on June 12—slightly ahead of schedule—but the state still received 23% less rainfall than normal. The previous year saw a delayed onset on June 20, resulting in a 20% rainfall deficit.
Data from 2020 to 2022 shows the monsoon typically entered Bihar on June 13, aligning with the historical average. However, since 2021, the state has not recorded rainfall above the seasonal normal of 1272.5 mm. An IMD official cautioned that early arrival in Kerala does not necessarily guarantee similar timing across the rest of the country, as monsoon progression is influenced by a complex interplay of global, regional, and local climate factors.
The IMD is scheduled to release its official monsoon forecast on May 15, which will provide more definitive information on the expected rainfall patterns and the timing of monsoon onset across different regions, including Bihar.