The climate of Uttar Pradesh (U.P.) is primarily defined as humid subtropical with dry winter (CWa) type with parts of Eastern U.P. as semi-arid (BS) type. Alternatively, some authors refer to it as tropical monsoon. Variations do exist in different parts of the large state, however the uniformity of the vast Indo-Gangetic Plain forming bulk of the state gives a predominantly single climatic pattern to the state with minor regional variations. U.P. has a climate of extremes. With temperatures fluctuating anywhere from 0 °C to 50 °C in several parts of the state and cyclical droughts and floods due to unpredictable rains, the summers are extremely hot, winters cold and rainy season can be either very wet or very dry