Why IMD’s city rain forecast is failing

‘Cities Across World Have Local Factors Affecting Rain-Causing Elements’

- Kushagra Dixit

New Delhi: There’s a bit of circumspection about India Meteorological Department’s rain forecasts these days. So many predictions have gone wrong that people are questioning the integrity of the 130-year-old organisation. However, experts believe that megacities worldwide, like Delhi, are facing similar forecast challenges because local factors such as aerosols, urban heat and high-rise buildings tunnelling the wind alter rain-causing conditions like moisture convergence, cloud formation, wind directions.

In Delhi, even the monsoon line of trough, which stretches from Rajasthan to Bengal, oscillates north and centre, making forecasting difficult. But this may be resolved by an upgrade in IMD’s systems by incorporating these factors and parallel weather indications, the experts added.