Monsoon 2021 had a speedy run over Peninsular India and the entire northeast region. Southwest Monsoon reached before time over Maharashtra, Telangana, and Andhra Pradesh. Monsoon also marched over northeast India with military punctuality and cover the entire region in one go, otherwise a rare event to witness. Though these are still early days but the monsoon walked with a brisk pace and the 1st week rainfall is nearly 40% more than normal. In the absence of any major weather system, daily rainfall spread may decrease over most parts except northeast India for the next 72 hours. Isolated moderate to heavy showers will continue over central parts and along the west coast.
As predicted earlier, a cyclonic circulation is likely to form on 09th June over the Gulf of Siam and adjoining Myanmar and Northeast Bay of Bengal. This will organize and also shift along the coast of Myanmar and Bangladesh on 10th June. A low-pressure area is expected to form the same day or next 24 hours over Bay of Bengal. This will strengthen to a depression on 11th June and also move closer to the coast of Odisha and West Bengal. This maiden system will revive active monsoon conditions over large parts of the country.
With the further movement of depression over land, the monsoon current will advance over West Bengal, Odisha, Bihar, Jharkhand, and Chhattisgarh before the scheduled date. Heavy rainfall will commence over coastal parts on 10th June and the spread and intensity will increase between 11th and 15th June over these states. Also, the western arm of the monsoon will accentuate over the Arabian Sea and widespread heavy rainfall is expected along the entire stretch of the west coast from Kerala to Konkan and South Gujarat during this period. Mumbai is likely to have the onset of Monsoon during this spell and heavy to very rainfall is expected during this period particularly between 13th and 15th June. South Coastal Gujarat will also receive early monsoon showers before they proceed over the mainland. Southwest monsoon may also make an early advance over parts of Uttar Pradesh and Madhya Pradesh by the middle of the month.