India monsoon lags, 72% of area faces rainfall deficit

India's southwest monsoon has progressed slowly since its onset in early June, leading to significant rainfall deficits across large parts of the country. The monsoon arrived in Kerala on June 4, three days later than normal, and its subsequent advance has been sluggish, with the northern limit remaining stagnant in Bihar for several days.

According to the India Meteorological Department (IMD), the country has received only 42.6 mm of rainfall in the first fortnight of the season, a 41% shortfall compared to the normal 72.2 mm. This has resulted in deficient rainfall across 14 states, covering nearly half of India's geographical area. Central India has been hardest hit with a 63% deficiency, followed by the Northeast at 46% and the Southern Peninsula at 21%. Only Northwest India has recorded near-normal rainfall, with a minor 2% shortfall attributed to western disturbances.

Scientists attribute the weak monsoon progression to a strong El Niño condition, which typically weakens monsoon rains over India, and the absence of typical weather systems over the Arabian Sea and Bay of Bengal. They note a weakening of the low-level southwesterly winds and cross-equatorial flow that...