India records its wettest July-August in 25 years

July and August this year, the main monsoon months, were the wettest India has seen in 25 years. Countrywide rainfall in the two months has been 10% above normal, the highest since 1994, met records reveal. The current month, with 16% above-normal rainfall across the country in 30 days so far, is set to be the wettest August in 23 years. July had ended with a 5% monsoon surplus.

This is also the first time since 2010 that both July and August have received surplus all-India rainfall — just the second time in the past 25 years — Indian Meteorological Department data reveals. The surplus rainfall in July-August was a dramatic change from the monsoon’s performance in June, which had a 33% rainfall deficit, the worst for the month in five years. “Both large scale and regional factors became favourable for the monsoon since July. First, El Nino, which normally disrupts the Indian monsoon, weakened considerably in July (and later dissipated). Meanwhile, conditions in the Indian Ocean became good for monsoon with the oceanic dipole turning positive,” said Mrutyunjay Mohapatra, director general of meteorology of IMD.

At the regional level, low pressure systems started forming over the Bay of Bengal and moving inland. “Four such systems formed in August alone. But it wasn’t the number alone. The systems remained active over the land for a large number of days, leading to vigorous monsoon conditions, particularly over central and peninsular India,” Mohapatra said.

However, at many places, the rainfall proved to be too much, too soon, and not much beneficial for kharif crops. While July got off to a wet start, the monsoon went into a 12-day hiatus from July 13, which delayed sowing in several states.

By July 25, the monsoon was nearly 20% below normal across the country, leading to concerns over another failed monsoon year. That’s when a 26-day period of intense rainfall began which not just wiped out the deficit but pulled the seasonal rainfall (since June 1) to a 2% surplus. Countrywide daily rainfall during this period remained higher than normal on all but three days.

That spell, fed by a number of low-pressure systems and one deep depression (much more intense than a low pressure), brought flood havoc to south, central and parts of north India, which again adversely hit agriculture. Overall, seasonal rainfall across the currently shows a zero deficit/surplus.

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