The festival of Holi has marked the end of winter and the arrival of spring/pre-monsoon, but intense heat has already gripped West and Central India, arriving earlier than usual.
A severe heat wave scorched parts of Saurashtra and Kutch through Thursday, and only with slightly less intensity over Gujarat, Vidarbha and Odisha. It will now spread to Odisha and Jharkhand and hang in there for four days; for three days over north coastal Andhra Pradesh and Yanam; and three days from Saturday over plains of West Bengal.
Crucial for monsoon
Heating up of land is crucial in terms of outlook for ensuing monsoon. It helps set up suitable temperature and pressure gradient relative to cooler seas around. This, in turn, links high pressure area (over seas) to a lower-pressure area (over land, Indian subcontinent) for moist monsoon south-westerlies to blow in from Arabian Sea/Bay of Bengal from June onwards.
Heating will progressively have to spread out to North-West India in May/June in continuum with adjoining south-east Pakistan in order that a seasonal ‘heat low’ develops. This is a low pressure area associated with high temperatures — as distinct from low-pressure areas over seas that brings clouds and rain ashore — and is instrumental in drawing the monsoon winds.
Emerging ‘heat low’
The ‘heat low’ phase witnesses oppressive heating of up to 50°C or more in areas such as Balochistan and Sindh in Pakistan; Phalodi and Churu in Rajasthan; and Rohtak in Haryana in May and June. On Thursday, the highest maximum temperature of 42°C was reported at Bramhapuri in Vidarbha, the India Meteorological Department (IMD) said.
Vishwas Chitale, Senior Programme Lead at Delhi-based think-tank Council on Energy, Environment and Water (CEEW), says heating trend is despite an ongoing weak La Nina event. January 2025 has emerged as the warmest January on record globally. In India, February 2025 was the warmest since 1901, with mean temperature at 22.04℃, 1.34℃ above normal, per IMD.
Above-normal warmth
Per IMD outlook, most parts of the country may experience above-normal maximum and above-normal minimum temperatures during March-May. Only exception will be South India and pockets of North-East India. Above normal heatwaves are likely during March-May except over North-East India, extreme North India, and south-western parts of Peninsular India.
Impact of La Nina and El Nino increase natural variability of increasing frequency, intensity and duration of extreme heat due to human-induced climate change, per World Meteorological Organisation. IMD’s Monsoon Mission Coupled Forecast System suggests weak La Nina will only last till March, and may switch to ‘neutral’ (neither El Nino nor La Nina) from March to May.
