Bihar Monsoon 2025: Early Arrival Likely via Seemanchal on June 4; Heavy Rainfall Expected This Year

Patna, May 27 — The southwest monsoon is expected to make an early entry into Bihar this year, likely arriving a full week ahead of schedule. According to meteorological forecasts, June 4 is being projected as the probable date for the monsoon’s arrival through the Seemanchal region, with Purnia and surrounding districts set to be the first to receive the seasonal downpour.

Early Monsoon, Excess Rainfall Predicted

Typically, the monsoon arrives in Bihar around mid-June, but this year, it is tracking earlier due to favorable conditions in the Bay of Bengal and an already active system in southern India. Meteorologists warn that above-normal rainfall — even excess rainfall (atiprashthi) — is likely across Bihar this season, especially in the northeast belt.

This could significantly boost paddy cultivation, offering an early start to the kharif cropping cycle. However, experts also caution that persistent heavy rains could trigger flooding, particularly in the low-lying Seemanchal areas and Nepal’s Terai region, which drain into northern Bihar.

Pre-Monsoon Rains Already Affecting Crops

Bihar has been witnessing intermittent pre-monsoon showers, which are expected to continue till June 1. While these have helped moderate soaring temperatures, they have also negatively impacted maize and moong crops, especially in rain-prone areas of Kosi and Purnia divisions.

Farmers report that the untimely rains during the harvesting stage have damaged yields. The meteorological department has advised vigilance until the monsoon formally sets in.

Kerala Saw Monsoon Advance by 8 Days

This early arrival in Bihar is part of a broader pattern. The southwest monsoon hit Kerala on May 24, eight days ahead of its usual June 1 onset. This shift has created ripple effects, with early rains forecast across multiple Indian states, including Goa, Maharashtra, West Bengal, and now Bihar.

Meteorologists are closely monitoring the atmospheric and oceanic conditions to assess whether this trend will result in more intense or prolonged monsoon activity across the Gangetic plains.

What This Means for Bihar

For now, residents in Purnia, Katihar, Araria, and Kishanganj should prepare for early rains, which may start as moderate showers and intensify in the following weeks. The State Disaster Management Authority (SDMA) has been put on alert in flood-prone areas, and agricultural departments are advising farmers to ready their paddy nurseries early.

The final monsoon forecast for June–September is expected to be released next week, which will provide more clarity on rainfall distribution and flood risk across Bihar.