This August recorded the highest rain—24% excess—for the first time since 1983, when 24% excess rain was recorded. In 1926, 33% excess rain was recorded in August.
Several parts of India, particularly central and some parts of western India including Gujarat and Rajasthan, recorded excess rain during the first three weeks of August. The week ending August 12 saw 13% excess, the week ending August 19 saw 42% excess, and the week ending August 26 saw 41% excess rain. IMD, in its weekly weather update Friday, said there will be above average rain at least until September 3. Rainfall could reduce thereafter as no low-pressure area is likely to form over the Bay of Bengal until around September 10. Five low pressure areas have already formed in August, bringing extensive and heavy rain to east, central and west India. Low pressure areas are the main rain bearing systems during the monsoon. In the week ending August 26, for example, Hairamgarh in central India recorded 23 cm; Jodia in Gujarat recorded 34 cm; Bhungra in Rajasthan recorded 36 cm, all in the extremely heavy rain category (over 20 cm).
There is a well-marked low-pressure area over north Chhattisgarh and the adjoining east Madhya Pradesh. It is very likely to move west-north-westwards across north Madhya Pradesh and south Uttar Pradesh during the next two days and weaken gradually, IMD said in its Friday morning bulletin.
The western end of the monsoon trough (line of low pressure) is near its normal position (Ganganagar to Bay of Bengal) and the eastern end to the south of its normal position. The western end is likely to remain in its normal position during the next two days and shift northwards to the foothills of Himalayas thereafter for the subsequent four or five days. “The convergence of strong lower level south-westerly winds from Arabian Sea and easterly winds from Bay of Bengal is very likely over the plains of Northwest India during next 2-3 days,” the bulletin read.
Due to these favourable conditions, very heavy rain is likely over Vidarbha and Chhattisgarh on August 28; over west Madhya Pradesh on 28 and 29; over Gujarat and Konkan and Goa on August 29. Widespread and extremely heavy rain are very likely over east Madhya Pradesh on August 28. Widespread and heavy rain is also likely over northwest India including Punjab, Haryana, Uttar Pradesh and Delhi on August 28 and 29, the bulletin read. IMD scientists warned of mudslides and flooding in parts of central India as the soil is already saturated there.
Overall monsoon rain is 8% excess with 23% excess rain over the south peninsula; 16% excess over central India; 12% deficient over northwest India and 4% excess over east and northeast India.