The long night of India’s heatwave
The Indian EXPRESS (28 May, 2026)
From poor sleep to higher mortality chances, rising nighttime heat is reshaping the country’s climate emergency.
Heat waves occur in India from March to June or July, and warnings are typically based only on the maximum surface air temperature (daytime). Daytime-only heatwaves (DHW) are increasingly turning into nighttime-only (NHW) and day-night compound heatwaves (CHW), and the conventional “hot-day and cool-night” no longer holds.
The dangers of warm nights and high indoor temperatures are thus increasingly gaining recognition. A recent analysis reveals that warm nights in northeast, northwest and peninsular India increased by two to eight days/decade and are projected to increase by 10–13 days/decade from 2015 to 2100. The forecast for the far-future (2080–2100) scenario: Warm nights (and days) are expected to rise sevenfold.
