IMD Announces Southwest Monsoon Withdrawal Timeline Starting September 19

The India Meteorological Department (IMD) announced that the withdrawal sequence of the Southwest Monsoon (June to September) is expected to commence from North-West India around September 19, 2026. Official data released by the weather agency indicates that despite isolated heavy precipitation events, the cumulative national monsoon rainfall deficit stands at approximately 15 percent compared to Long Period Average (LPA) benchmarks.

The withdrawal of the monsoon is declared when specific atmospheric criteria established by the IMD are satisfied: cessation of rainfall activity over West Rajasthan for five consecutive days, establishment of an anticyclonic circulation at 850 hPa level, and a substantial reduction in moisture content. The Southwest Monsoon provides nearly 75 percent of India's total annual rainfall, acting as the primary driver of kharif agricultural output and reservoir replenishment.

Monsoon patterns are heavily influenced by global macro-climate phenomena such as El Niño-Southern Oscillation (ENSO) in the Pacific Ocean and the Indian Ocean Dipole (IOD). The IMD classifies seasonal rainfall based on LPA departures: normal (96-104%), below normal (90-95%), and deficient (below 90%). A 15 percent deficit raises localized concerns for post-monsoon soil moisture retention and winter rabi crop sowing preparation.

Understanding monsoon dynamics is vital for assessing agricultural yields, rural demand, and food inflation metrics. For civil service exams, this topic frequently yields Prelims questions on IMD withdrawal criteria, El Niño/IOD mechanisms, and LPA definitions, as well as Mains GS Paper-1 Geography questions.