South India records 2nd highest maximum temperature in April in 123 yrs, IMD warns of more heatwaves

New Delhi: Southern India has recorded its second highest maximum temperature in 123 years in April, the India Meteorological Department said here on Wednesday, noting that four out of five maximum temperatures for the peninsula region were registered in the span of the last eight years.

IMD director general Mrutyunjay Mohapatra said 2016, 2024, 2017, 2019 and 1906 were the years of the highest maximum temperature for the southern region, suggesting a clear increasing trend in maximum temperature for the region in recent years. No such trend has been seen in other regions.

Sweltering May

Mohapatra warned that May would witness 5-8 additional days of heatwave over and above the normal days as a result of which a large part of western and central India could experience 8-11 heatwave days whereas several other areas including north Karnataka might see 5-7 heatwave days.

Above normal maximum temperatures are likely over most parts of the country in May except the north-east, pockets of northwest that will encounter yet another Western Disturbance between May 3-5 and central India and adjoining areas.

Five active Western Disturbances – a storm that originates in the Mediterranean - led to rain, thunderstorm, and hail storms over north and central India at regular intervals in April, preventing heat waves.

On an average, three days of heat waves occur in May in Rajasthan, Gujarat, Maharashtra and Madhya Pradesh. But this year, the number of such days could be 8-11 for southern Rajasthan, western Madhya Pradesh, Vidarbha, Marathwada region and Gujarat.

No respite for Bengal, Odisha

West Bengal and Odisha are among the states that will witness more heatwaves in May even though the two eastern states are already reeling under sweltering heat for an extended period of 16 and 18 days respectively in April. On Monday several stations in West, Bengal, Bihar, Odisha, Telangana, Rayalaseema and coastal Andhra Pradesh reported heatwaves.

A vendor selling snacks and refreshment drinks waits for customers outside Alipore Zoological Garden on a hot summer day in Kolkata.

“Heatwaves in the southern peninsula and east are a new phenomenon. This has happened due to El Nino (an anomalous rise in the sea surface temperature in the Pacific) that led to more heating of the land mass. Also there has been a wind discontinuity,” Mohapatra said.

Rise in heatwave duration

The World Meteorological Organisation too predicted a hotter-than-usual May for the entire Indo-Pacific region. The IMD has earlier shown that in the heatwave areas of India, the total duration of heatwaves has increased by about three days in the last 30 years.

Mohapatra said this year, there have been no thunderstorm activity in eastern states (Kalboisakhi in West Bengal) and barely any thunderstorm in the south, further pulling up the mercury. This has happened because of the formation of an anticyclone over the Bay of Bengal that prevented entry of moisture-laden sea breeze over the landmass.