NEW DELHI: Large parts of north, east and central India may witness summers getting hotter as temperatures might rise by a 1-1.5 degree celsius than normal in these regions in April and May, suggests the India meteorology department (IMD) model.In March, the temperature is likely to rise by half a degree celsius across the north Indian plains, central India, south India and eastern India. In northern Andhra Pradesh , it may rise by a degree celsius, the coupled forecast model suggests.Several parts of the country have been already witnessing a rise in mercury.The IMD scientists, however, said they are calibrating the data and will come up with a forecast for the next three months by the end of February.The IMD also releases summer forecast ahead of the summer season.In April, the temperature is likely to rise by a degree celsius than normal over north and central India, the models suggests. In parts of west Rajasthan and adjoining Gujarat , the temperature may rise by 1.5 degree celsius.Rajasthan, especially the western part of the state, has been witnessing unusually high temperatures. In May last year, Churu and other neighbouring districts recorded temperatures hovering around 50 degree celsius.May is considered as one of the hottest months recorded in the country.The central India, north Indian plains and the eastern India is also likely to see the temperature rising more than normal by a degree celsius in May. The temperature may rise by 1.5 degree celsius in west Rajasthan.