India: New initiatives in prediction of thunderstorms and associated weather

Taking into account the devastations caused by the severe thunderstorms during premonsoon months of March-April-May in 2018, over different parts of India and particularly the northern and northwestern region, Ministry of Earth Sciences took a time targeted developmental work. Under the chairmanship of Secretary, MoES, a brain storming meeting was held on 1 June 2018 and subsequently a MoES working group was formed to develop the tools for predicting thunderstorm occurrence as well as lightning flash, lightning probability, heavy rain, gusty wind etc. upto 24 hour lead time and outlook for 48 hour lead time.

Under this new initiative, for improving detection of thunderstorms location and associated lightning, high resolution satellite observations, lightning sensor observations (from IITM and IAF) and Radar observations have been merged to develop user friendly high spatiotemporal operational products. Scientists from IITM, IMD and NCMRWF coordinated together and developed holistic thunderstorm specific products for nowcast (upto 3 hours), short range forecast upto 24 hours from high resolution mesoscale model and 48 hour outlook from high resolution global model. Specific products developed by the team are as follows:

1. For nowcasting 2-3 hours ahead of current time, nowcast model SWIRLS for thunderstorm prediction has been implemented for 11 individual Doppler radar stations of IMD.
2. For prediction upto 24 hours ahead at three hour intervals, high resolution mesoscale models (WRF) of IITM and IMD and the NCUM Unified model have been utilized to develop thunderstorm specific products and provide the guidance at district level.
3. To get thunderstorm guidance upto 48 hour, the Global Forecast System and NCUM Unified model (at 12 km spatial resolution) have been utilized to develop several thunderstorm specific products.

These new prediction tools have been utilized since 01 April 2019 for thunderstorm forecast guidance over different parts of India. Currently, IMD issues three hourly thunderstorm nowcast for around 433 stations. IMD is also issuing district level nowcasts for thunderstorm occurrence and related severe weather for all districts of India through whatsapp, SMS, e-mail and IMD website.

The information is being communicated to state and national level stakeholders including concerned District Collectors, Disaster Management Authority at state and national level and Electronic Media. To better communicate the prediction and warning of thunderstorms to public/society and stake holders, a dedicated website has also been prepared where all these information is available with latest update and details. This site can be accessed here.