The Mumbai civic body on Saturday declared a holiday for the afternoon session in all schools and colleges across the metropolis after the India Meteorological Department (IMD) issued a red alert of extremely heavy rainfall.A spokesperson of the Brihanmumbai Municipal Corporation (BMC) said that the decision was taken keeping in mind the safety of students amid the forecast of extremely heavy rains.The BMC also appealed to citizens to step out of homes only if necessary as heavy rains continue to lash several parts of the city, he said.The IMD issued the red alert for Mumbai, warning of extremely heavy rainfall at isolated places during the day.Despite the late arrival of monsoon, the country’s financial capital has been witnessing heavy rain since the beginning of this week.Several parts of Mumbai received more than 100 mm of rainfall during the 24 hours ending at 8 am on Saturday.According to civic officials, public transport services, including suburban local trains, are operating normally, although passengers have complained of delays on the railway network.