Low-pressure system near Kolkata brings heavy rain to Vijayawada, but leaves Vizag bone dry

Vijayawada has been experiencing heavy rain for the past two days due to a low-pressure system in the Bay of Bengal, near Kolkata. Several low-lying areas in the city have been submerged, triggering the fear of flooding among the residents.

But the situation in Visakhapatnam is completely different. It has not received even 10 mm of rain, indicating that the low-pressure system has no effect on the Port City.

Explaining the reasons behind the weather phenomenon, S. Karuna Sagar, a scientist with the India Meteorological Department (IMD) at its Amaravati centre, said, “The rainfall associated with the low-pressure systems depends on the wind direction. Generally, the outer bands of the low-pressures and the troughs connected to the system play a key role in rainfall activity.”

The low-pressure system formed in the Bay of Bengal, near Kolkata, travelled towards South Coastal Andhra Pradesh, via South Odisha and Chhattisgarh, and its trough also passed over South Coastal Andhra Pradesh. “Therefore, the region, including Vijayawada, has received heavy rainfall, causing submersion of the low-lying areas,” he said.

“Only when the wind direction comes from the sea (Bay of Bengal) towards the North Coastal region will areas such as Visakhapatnam city have higher chances of heavy rainfall. The hills surrounding the Port City are also a reason, because the hills usually stop the low tropical winds. These factors can be some of the reasons behind the lack of rainfall activity in Visakhapatnam. Moreover, there will be no wet weather conditions for Visakhapatnam, and or formations of low-pressure systems over the sea for the next week. This means, no rainfall. The city may experience dry, clear sky conditions,” Mr. Karuna Sagar told The Hindu on Sunday (July 27).

This weather pattern is a cause for worry for the residents, as drinking water crisis loom large with the groundwater level plummeting due to lack of rainfall during the southwest monsoon season. Due to depletion of water in the borewells and lack of proper municipal water supply, the residents, especially apartment dwellers, in the areas such as PM Palem are relying on water tankers.

“We are spending ₹5,000 to ₹8,000 per day for water tankers as the water level in our borewell has gone down due to lack of rainfall,” says B. Rambabu, an apartment resident.

The groundwater levels in the State have recently shown a mixed trend. While the levels have increased in some districts, it has seen a decline in other areas. Some areas have seen an improvement due to heavy rainfall, especially in Rayalaseema, while other areas, especially those with high groundwater use, have experienced a decline.

“Rainfall patterns, groundwater use, and the type of geological formations play a key role in determining groundwater levels,” says Ch. Durga Rao, a geologist.