The fiercest heat of the year descended on northern India this weekend, with the capital New Delhi recording its highest April temperature since 2022. On Saturday, the mercury at the Safdarjung observatory, the city’s benchmark, touched 42.8°C, a full five degrees above normal and enough to trigger the weather bureau’s official heatwave criteria. Across town, the Ridge weather station logged 43.1°C the previous day, while overnight temperatures offered little respite, a pattern that officials warn can be especially dangerous for the elderly and those without shelter.

Viewed from Lucknow, the picture was even more punishing. The state of Uttar Pradesh placed nearly 70 of its 75 districts under a severe heatwave alert, as Prayagraj baked at 45.2°C. Hot, dry winds swept across the Gangetic plain, with maximums ranging from 42°C to 45°C in cities such as Noida, Ghaziabad and Varanasi. The heatwave also stretched west into Punjab, Haryana and Rajasthan, and east into Bihar and Jharkhand, leaving a vast swath of South Asia’s most densely populated region sweltering under conditions that the India Meteorological Department described as four to eight degrees above seasonal averages.

The sudden spike has prompted the central government in New Delhi to issue an urgent advisory, instructing state administrations to activate heat action plans and step up hospital preparedness. Officials in the health ministry worry that if such extremes persist, heat-related illnesses could mount rapidly, while economists tracking the informal sector note that outdoor labourers—construction workers, street vendors, farmhands—face the sharpest productivity losses. A heatwave this early in the year, analysts in Mumbai observe, compresses the window for pre-monsoon activity and raises food-price risks if the blistering heat spreads to wheat-growing belts.

Meteorologists, however, hold out the prospect of imminent relief. A western disturbance, a moisture-laden system from the Mediterranean, is forecast to affect the western Himalayas from Sunday and gradually shift eastwards. This is expected to trigger thunderstorms and gusty winds over Delhi and the plains of north-west India from Monday, with the capital likely to see overcast skies and a drizzle by Tuesday. Rainfall is also predicted over Uttar Pradesh from 26 to 30 April, which should drag maximum temperatures down from their current punishing highs. For now, the IMD has placed Delhi under a yellow alert for Sunday, warning that isolated pockets could still endure heatwave conditions before the change sets in.

The early blast of extreme heat fits a pattern that climate scientists in London have been tracking for years: India’s heat season is arriving sooner and growing more intense. While an April shower may offer short-term relief, the broader concern is that the monsoon window is narrowing, and the intervals of deadly heat between pre-monsoon rains are lengthening. As the country braces for what is almost certain to be another record-hot summer, the weekend’s temperatures serve as an unignorable reminder that adaptation—from cool roofs to staggered working hours—must move from pilot projects to nationwide policy with far greater urgency.