Heatwaves in northeastern and eastern India, including Kolkata, Agartala, Imphal, and Shillong, were reported last week. Some stations in Imphal reported a maximum close to 40C, a threshold usually associated with plains and deserts. India Meteorological Department?s gridded temperature data-set analysis shows that while the area that sees temperatures reaching at least 40 degrees has not expanded, there is a clear increase in area on days when the temperature has reached the 40 degree threshold. The 40 degree threshold arrives earlier and leaves later than it did before.