IMD issued red and orange alerts for Delhi-NCR due to expected heavy rainfall. Up to 200 mm predicted for east NCR, including Noida, Ghaziabad. Several parts of Delhi-NCR, particularly Uttar Pradesh's Noida, Ghaziabad, received nonstop heavy overnight rainfall that continued on Thursday morning, causing severe waterlogging and slow movement of traffic as a result.A drone visual of the vehicles moving slowly amid a traffic jam on the Delhi-Gurugram Expressway, in Gurugram on Wednesday. (ANI)The India Meteorological Department (IMD) issued a red alert for all parts of Delhi, warning of extremely heavy rainfall, while an orange alert was sounded for parts Ghaziabad, Noida, Meerut and Gurugram, with more intense showers expected through the day. Track July 9 rain updates here‘Massive rainfall event’ for Delhi, GhaziabadWeather enthusiasts tracking the monsoon system warned on Thursday morning that the ongoing spell could intensify further over the next few hours. Amateur weatherman Navdeep Dahiya said in a post on X Delhi-NCR was entering a "massive rainfall event" over the next 24 hours as the region lies in the western quadrant of a low-pressure area.According to him, the next 12 hours would be the most crucial, with consistent light to moderate rain punctuated by frequent heavy downpours.He said eastern parts of the NCR, including Noida, Ghaziabad, north and east Delhi, were likely to bear the brunt of the system and could receive up to 200 mm of rainfall, while central, west and south Delhi, along with Faridabad, may receive between 100 mm and 150 mm. Gurugram could see 70 mm to 150 mm of rainfall. Dahiya also cautioned residents against venturing outdoors unless necessary, warning of widespread waterlogging, particularly across east NCR and adjoining parts of Delhi.His X post read, "We are in for an massive rainfall event in Delhi NCR within the next 24 hours, siting at the western quadrant of low pressure area.• Next 12 hours till late evening are most crucial.• Consistent light to moderate showers will occur with frequent spells of heavy downpours.• East NCR (Noida, Ghaziabad, north and east Delhi) will be most affected with consistent heavy rains - fresh 200mm rains possible.• Central, west, south Delhi, Faridabad can receive 100 to 150mm.• Gurgaon b/w 70 - 150mm.• East central Haryana along with Chandigarh to expect 40-100mm spells.Avoid outdoors unless absolutely necessary, high chances of water logging in most parts specifically in east NCR and adjoining Delhi. Stay Safe".Another amateur weather enthusiast's X page, India Skymet Weather, also flagged the possibility of an intense rainfall spell, saying a passing low-pressure area embedded in the monsoon trough was moving north of Delhi, with its western and southwestern quadrant expected to impact Delhi-NCR throughout the day.It forecast persistent heavy rainfall with intense convective cloud activity, estimating 180 mm to 250 mm of rain over east Delhi, east NCR, Ghaziabad, Noida, Baghpat and Meerut over the next 24 hours.IMD weather alertsAll districts of Delhi were under a red alert for rain on Thursday morning, according to the nowcast seen on IMD website at around 8:45 am. Delhi's adjoining areas of Ghaziabad, Noida (Gautam Buddh Nagar) as well as Haryana's Gurugram were under an orange alert parallelly over thunderstorm and moderate to intense spell of rain.The IMD has forecast continued rainfall over Delhi-NCR over the next few days, with authorities advising residents to avoid unnecessary travel, remain alert for waterlogging and traffic congestion, and monitor official weather advisories.Traffic chaos, waterloggingThe rain activity across Delhi-NCR has led to severe waterlogging and hours-long traffic chaos in several parts of the cities, especially Gurugram, prompting private offices to issue work from home advisory for employeesRoads across Gurugram remained inundated on Wednesday and Thursday, with traffic moving at a crawl on key stretches, including the Delhi-Jaipur Highway service lane near Narsinghpur, Basai, Kadipur and Sohna Road. Several vehicles reportedly broke down in waterlogged areas, leaving commuters stranded for hours.According to officials, teams from the Municipal Corporation of Gurugram (MCG), Gurugram Metropolitan Development Authority (GMDA), police and other agencies have been deployed to clear waterlogged stretches and regulate traffic. Waterlogging has been reported from Sectors 31 and 39, Sheetla Mata Mandir Road, Sector 10A, Pataudi Road, Basai Road, Kadipur and Umang Bhardwaj Chowk, among other areas.Traffic moves slowly during heavy rain at the Ashram Flyover in Delhi, on Wednesday (RAJ K RAJ /Hindustan Times)IMD said several parts of Delhi-NCR recorded significant rainfall between 8:30 am on July 8 and 6 am on July 9. In Delhi, Mehrauli recorded the highest rainfall at 83 mm, followed by Lodi Road (79 mm), Pusa (73 mm), Chhatarpur (68 mm), Mayur Vihar (66 mm), Janakpuri (62 mm), Narayana (57 mm), Pragati Maidan (46 mm), Najafgarh (42 mm), Mungeshpur (40 mm), Jharoda Kalan (33 mm) and Jafarpur (6 mm).In the NCR, Ghaziabad's Kamla Nehru Nagar received the highest rainfall at 143 mm, while Hindon recorded 53 mm. In Gurugram, rainfall was comparatively lower, with North CAP University recording 27 mm and KVK 21 mm during the same period. The rainfall data comes as the IMD has issued a red alert for Delhi and an orange alert for surrounding NCR districts, warning of more heavy rain and the possibility of waterlogging and traffic disruptions through the day.