After making a later revival, the southwest monsoon is expected to start withdrawing from northwest parts of the country from September, senior met department officials said. Earlier, India Meteorological Department (IMD) officials had said that monsoon withdrawal could start from Sep 15-20, but this too got delayed because of favourable weather conditions.
Usually, the southwest monsoon starts retracting from the southwest parts of the country around September 1. However, this year it has been delayed because of strong disturbances both in the Arabian Sea and Bay of Bengal. Overall, the cumulative rainfall shortfall across the country is now just 5% below normal, a remarkable turnaround from the almost 20% deficiency in end July.
During the week ending September 19, India received around 44% above average rainfall. According to the met department, monsoon is considered to have withdrawn from a certain area if the following three conditions are met. The first is cessation of rainfall activity for continuous five days or considerable reduction in moisture content and establishment of anti-cyclone in the troposphere.
Met department officials said, overall across the country, rainfall by the end of the season should be in line with the second stage forecast made on June 22. The IMD had said that cumulative rainfall across the country would be 96% of Long Period Average (LPA), which is normal.
Rainfall is considered to be normal when it is within 96-104% of the LPA. Long Period Average is the average rainfall across the country during the four-month southwest monsoon season during a 50 year period starting from 1951. It is estimated to be around 89 centimeters.
India’s kharif sowing, mainly that of coarse cereals, pulses and oilseeds has been impacted by the delayed onset of monsoon. However, it is expected to make some gains because of late resurgence.
Southwest monsoon is crucial for Indian agriculture as 55 percent of India's farmland is without irrigation. Rains below 90 percent of long-term averages are considered deficient - a drought in layman's terms.
In 2009, when India, whose huge land mass contains nearly all climates and soil types, faced widespread drought, monsoon rains were 22 percent below average. The country had to import large amounts of sugar then, pushing global prices to 30-year highs. EoM
