India, May 19 -- Delhi-NCR is under a yellow heatwave alert for May 19 and 20, with temperatures forecast to touch 45degC in isolated pockets.

Safdarjung recorded 43.4degC on May 18, Delhi's hottest day of the season so far, while Ridge and Ayanagar crossed 44degC.

Environmental campaigners say dense, concrete-heavy neighbourhoods may be experiencing far higher heat because of the urban heat island effect.

Delhi is bracing for another spell of severe heat, with official forecasts warning that temperatures could climb to 45degC in isolated pockets of the capital, even as environmental campaigners say people in dense urban neighbourhoods may already be experiencing far higher temperatures because of the urban heat island effect.

The Ind...