Under the Köppen climate classification, the city features a Tropical monsoon climate. Since the region lies in the south western coastal state of Kerala, the climate is tropical, with only minor differences in temperatures between day and night, as well as over the year. Summer lasts from March to May, and is followed by the South-west monsoon from June to September. October and November form the post monsoon or retreating monsoon season. Winter from December through February is slightly cooler, and windy, due to winds from the Western Ghats.