Southwest Monsoon arrives in Mumbai; IMD declares official onset

Mumbai finally witnessed the official onset of the southwest monsoon on Tuesday nearly a fortnight later than its normal arrival date of June 11 The delayed onset brings an end to speculation over its progress with the India Meteorological Department IMD confirming that the monsoon has now advanced over the financial capital and the rest of MaharashtraSouthwest monsoon made its onset over Mumbai on June 23 India Meteorological Department IMD scientist Sushma Nair saidThe normal date for the monsoons arrival in Mumbai is June 11Its the citys latest monsoon arrival since June 25 2023 The onset would also rank among the most delayed in the past decade though it would still fall short of the June 25 arrivals recorded in 2019 and 2023 which remain among the latest onsets in recent yearsContrast with recordearly arrival in 2025In 2025 the southwest monsoon officially arrived in Mumbai on May 26 making it the earliest onset over the city in 75 years This recordbreaking arrival was 16 days ahead of the normal onset date of June 11 brought on by the rapid development of a lowpressure system in the Arabian SeaIMD confirms further monsoon advanceThe IMD said the Southwest Monsoon has further advanced into the remaining parts of the central Arabian Sea some more parts of Maharashtra including Mumbai remaining parts of Telangana amp Odisha and some more parts of Chhattisgarh Jharkhand and Bihar today the 23rd of June 2026The Northern Limit of Monsoon passes through 20degN60degE 20degN65degE 20degN70degE Dahanu Wardha Raipur Daltonganj Motihari and 283degN83degE as on 23rd June 2026Conditions favour further advanceConditions are favourable for further advance of the southwest monsoon into some parts of the North Arabian Sea amp Gujarat some more parts of Maharashtra and Chhattisgarh and some parts of Madhya Pradesh during the next 23 days remaining parts of Jharkhand amp Bihar and some parts of Uttar Pradesh during the subsequent 34 daysMumbais monsoon arrival dates show wide variationsIMD data from 1950 to 2025 highlights the wide variation in Mumbais monsoon onset dates Although June 11 is considered the normal onset date the monsoon has arrived as early as May 26 and as late as June 25 underscoring the considerable yeartoyear fluctuations in the citys rainy seasonAccording to the data the earliest monsoon onset was recorded on May 26 2025 making it the earliest arrival in Mumbai since records began in 1950 Prior to that the monsoon had arrived on May 29 in 1956 1962 and 1971 On the other hand the latest onset dates were recorded on June 25 in 1959 2019 and 2023 while several other years saw the monsoon reach the city only during the third or fourth week of JuneThe data also highlights that monsoon arrival dates have shown no fixed pattern over the decades In the 1950s onset dates ranged from May 29 to June 21 The 1970s witnessed both very early arrivals such as June 2 and June 3 and delayed arrivals extending to June 24 Similar fluctuations continued through the 1980s 1990s and 2000s with the monsoon arriving anywhere between late May and late JuneLast decade highlights monsoon variabilityIn the last decade alone Mumbai has witnessed substantial variation in onset datesmdashfrom June 20 in 2016 and June 25 in 2019 to the record early arrival of May 26 in 2025 The data underlines the highly dynamic nature of the southwest monsoon and the influence of multiple atmospheric and oceanic factors on its progress along Indias west coastMumbai Monsoon Onset Dates 2015ndash20252015 June 82016 June 202017 June 102018 June 92019 June 252020 June 142021 June 92022 June 112023 June 252024 June 62025 May 26