Seasonal rainfall of southwest monsoon 2022 stands at 109%, between 01st June and 25thAugust. Earlier, opening month of June had started on a soft note and observed shortfall of 8%. Monsoon picked up pace thereafter and July gathered whopping surplus of 17%, highest since July 2005. August retraced track of July, except with some stops in the 1st and 3rd week. Still, the month of August is running surplus with 11% rainfall, between 01st and 25thAug.
Core monsoon months of July and August have held the reins of the season. Adequate rainfall with decent temporal and spatial distribution has been observed over most parts, outside Northeast India and states of Uttar Pradesh, Bihar and Jharkhand. However, the surplus rains observed so far, may take a dip, particularly over the northern and central parts.
Presently, there are 2 meteorological systems controlling the weather activity over different parts. Cyclonic circulation over Jharkhand and Madhya Pradesh region will meander over the region for the next 3-4days and take a recourse towards Uttar Pradesh, later. This will take the monsoon trough close to the foothills in the closing days of August and start of September. As such, circulation is rather weak and unlikely to trigger heavy rains over large area. Scattered rain and thundershowers are likely over Madhya Pradesh, Chhattisgarh, Odisha, Jharkhand, Bihar, West Bengal and Uttar Pradesh in the next 5-6 days. Drag of monsoon trough close to the foothills will shrink the spread and reduce the intensity of weather activity. There is no indication of any other system coming up over Bay of Bengal during the 1st week of September.
Weather activity will pick up over South Peninsula during next one week. Most sub divisions will experience rain and thundershowers, moderate in strength and heavy at few places. This is in association with a persisting cyclonic circulation and north-south trough over Tamil Nadu. This feature will gradually shift westward, covering Rayalaseema, Karnataka, Kerala and the coastline from Kerala to Goa. Fairly widespread monsoon activity is likely over the interiors of South Peninsula first and shifting along the coast later.
The northern and the central parts will observe least weather activity during the next 2 weeks. As such, the monsoon starts showing signs of withdrawal, anytime from 1st week of September onward. Pan India average daily rainfall amounts during last days of August are pegged at 7mm. Month of September witnesses drop of daily rainfall from 6.5 - 7.0mm in the 1st week to 6.0mm half way through the month. In the 3rd week, it lowers further to 5-5.5mm and less than 5mm in the closing days of the month. Overall, the month of September slogs for rain with an expected normal of 170mm.
Month of September may not be as active as the core monsoon months of July and August. Environmental and oceanic conditions, closer home, may restrict frequent bursts of monsoon. Weather systems over Bay of Bengal not likely to be as frequent as they were in August. Rainy days may take a toll and the surplus margin, achieved so far, may contract in the closing phase of monsoon.
