Cyclone Ditwah and its remnants stalled for several hours near the Tamil Nadu coast, causing heavy and prolonged rain. The system got trapped in a calm 'col' zone between two opposing anticyclonic circulations in the upper atmosphere. This slow movement drew in more moisture, leading to fresh rain clouds hitting areas near Tiruvallur and Chennai. B. Amudha, Head (Additional in-charge) of the Regional Meteorological Centre, said, "The system, lodged between two anticyclonic circulations, was oscillating under the push and pull of surrounding winds." She added, "It is difficult to forecast such microphysical changes that happen continuously in the atmosphere, much ahead and rapid changes can be tracked only over short periods." Meteorologists noted that weather models struggle to predict stalled movements in tropical cyclones. Y.E.A. Raj, former Deputy Director of Meteorology in Chennai, mentioned that Ditwah was a marginal cyclone with winds up to 40 knots. The cyclone slowed to 2-3 kmph, which was unexpected. Unlike normal cyclones that curve north or east and speed up, Ditwah moved southwestward, a rare path seen only three times in nearly four decades. Raj said, "The delay in rainfall was due to vagaries of weather, as the system’s behaviour was influenced by rapidly changing atmospheric conditions." The system was expected to move away from the coast by December 1 but remained nearly stationary for hours, intensifying rain over the region.