The India Meteorological Department (IMD) has forecasted continued heavy rainfall in Gujarat and surrounding regions, with the possibility of a cyclonic storm named Asna forming over the northeast Arabian Sea by Friday. This comes as the monsoon remains unusually active over northwest India, a trend that began in August and is expected to persist into the first week of September.
According to meteorologists, the deep depression currently over Saurashtra has caused severe flooding in parts of Gujarat. Meanwhile, a separate low-pressure system over eastern India has brought heavy rainfall to the eastern states. The Delhi-NCR region has also experienced several spells of heavy rain due to the proximity of a monsoon trough.
IMD officials have indicated that the deep depression over Saurashtra and Kutch is likely to intensify into a cyclonic storm as it moves over the northeast Arabian Sea. “The deep depression over Saurashtra, which has been sustaining for several days, will find favorable conditions to strengthen into a cyclone over the Arabian Sea,” a senior IMD official explained. “The system will gain energy from the warm ocean waters, with low wind shear and favorable Madden Julian Oscillation conditions, making it conducive for intensification.”
While it is relatively uncommon for a weather system that forms over land to develop into a cyclone once it reaches the ocean, this is not unprecedented. The IMD official noted that similar occurrences have been recorded twice in the past, including a depression that formed over Saurashtra and later became a cyclone over the Arabian Sea.
In addition to the potential cyclone, a low-pressure area over the Central region and the adjoining north Bay of Bengal is expected to cause very heavy to extremely heavy rainfall over Odisha, Coastal Karnataka, Kerala, and Mahe. Heavy to very heavy rainfall is also anticipated in North Coastal Andhra Pradesh, Chhattisgarh, Vidarbha, and Telangana over the next two to three days.
Rainfall activity is expected to increase again over northwest India, including Delhi NCR, starting from September 1. “Rain will decrease over the next two days in northwest India but is expected to intensify again from September 1 when the monsoon trough shifts back to its normal position,” said Mahesh Palawat, Vice President of Climate and Meteorology at Skymet Weather. “We anticipate isolated heavy to very heavy rain in the region on September 2 and 3.”
Since the beginning of the monsoon season on June 1, India has recorded 7% more rainfall than the average. Central India has experienced a 17% surplus, while northwest India has seen a 2% excess, Peninsular India an 18% surplus, and east and northeast India an 11% deficit. In August alone, rainfall was 15.9% above average for the country, with northwest India experiencing a significant 31.4% surplus.
Despite the overall increase in rainfall, certain regions have faced deficits. Over northwest India, rainfall has been 76% above average since June 1, with a 39% surplus in east Rajasthan. However, Jammu and Kashmir and Ladakh have seen a 27% deficiency, Punjab a 29% deficit, Himachal Pradesh a 22% deficit, and the Haryana, Chandigarh, and Delhi subdivision a 16% deficit.
“The monsoon remains in an extremely active state across the country, driven by two major weather systems—one over Rajasthan and another over Gangetic West Bengal,” stated M Mohapatra, Director General of IMD. “There is already extremely heavy rain over Gujarat, with more very heavy rainfall expected in the coming days. East India is also likely to receive significant rainfall, while Delhi NCR, Haryana, and Punjab are forecasted to see sporadic rain and thundershowers throughout the week.”
The development of cyclonic storms in August over the Arabian Sea is a rare event. Historically, only three cyclonic storms have formed over the Arabian Sea in August from 1891 to 2023, occurring in 1976, 1964, and 1944. The 1976 cyclone originated over Odisha, moved west-northwest, entered the Arabian Sea, made a looping track, and eventually weakened near the Oman coast. Similarly, the 1944 cyclone intensified after entering the Arabian Sea but weakened over the water. A shorter cyclone developed near the South Gujarat coast and dissipated near the coast in 1964.
Similarly, over the Bay of Bengal (BoB), there have been a total of 28 such systems in the month of August over the past 132 years, according to the IMD.
The situation remains dynamic, with the IMD closely monitoring developments as the monsoon season continues to impact large parts of India.