Monsoon likely to reach city after 1st week of June
Times of India | 31 May 2024
Kolkata: The Southwest monsoon, which began in Kerala on Thursday afternoon, is expected to extend to parts of north Bengal within the next 72 hours. Following the first week of June, it will progress towards Kolkata and other areas of south Bengal.
On Thursday, the Regional Meteorological Centre announced that the monsoon is likely to advance into sub-Himalayan West Bengal and Sikkim within 2-3 days from the time of its onset over Kerala.“Normally the Southwest monsoon takes about seven days to reach south Bengal after making its way into north Bengal. Over the next week, Kolkata is likely to remain cool and cloudy due to moisture incursions coming from heavy rainfall in the north, produced by the monsoon’s march into the state,” said RMC head of weather, H R Biswas.
Thus a tentatively view for monsoon’s onset into the city would be any time between June 8 and June 12. Last year, monsoon arrived in Kolkata on June 19, deviating from the normal arrival date of June 10. Over the last decade, the years 2018, 2020 and 2021 were closest to this mark, with the Southwest monsoon sweeping into the city between June 11 and 12 during those years.
This year, the Southwest monsoon entered Kerala two days before its usual arrival date, but this has limited correlation with the onset date in south Bengal. In 2022, the arrival date in Kolkata was as late as June 18, 20 days after its onset in Kerala on May 29. While the Bay of Bengal is unlikely to see any major systems anytime soon, after the passing of the only pre-monsoon Cyclone Remal, monsoon entering the state is likely to keep the conditions favourable to facilitate the frequent development of overland systems over the next week. By Thursday, a trough ran from a cyclonic circulation over northwest Uttar Pradesh to west Bangladesh, across southeast Uttar Pradesh, south Bihar and north Bengal and Sikkim, at 0.9 km above mean sea level, producing heavy rains in north Bengal districts.
“The onset of Southwest monsoon in south Bengal typically breaks a heat spell in the region. During the onset period, north and south Bengal have an inverse relation in the magnitude of rainfall, such that one is relatively dry and the other experiences heavy rain. However, there is unlikely to be any chance of very hot weather in the first week of June in Kolkata,” added Biswas.
By Thursday, Southwest monsoon had also partially moved into most northeastern states. Due to moisture incursions moving southwards from the systems forming near north Bengal, Kolkata and its neighbouring south Bengal districts are likely to get light rain and heavy clouds over the next seven days. Absence of prolonged sunshine is likely to keep the day temperature cool,under 35°C over the course of the week. On Friday, maximum is likely to remain at 34°C while minimum is likely to drop from 30.2°C to 29°C.