Cloudburst and Rainfall Trends in India
The recent weather patterns in India have shown significant activity, particularly with the monsoon season and instances of cloudbursts. As outlined by Director-General of the India Meteorological Department (IMD), there are noteworthy trends and statistics regarding rainfall and cloudbursts.
Cloudburst Trends
- No Increasing Trend: There is no observed increasing trend in cloudbursts over India recently.
- Mini Cloudbursts: There has been an increase in ‘mini cloudbursts’ — defined as 5 cm of rain per hour.
- Definition and Forecasting: A cloudburst is defined as 10 cm of rain in an hour over 20-30 square km. Forecasting remains challenging, and cloudbursts are typically reported within 24 hours after the event.
Monsoon Rainfall Patterns
- Above Normal Rainfall: Rainfall from June 1 to August 31 was 6% above the normal 70 cm.
- Regional Variations:
- Northwest India experienced 26% more rain than usual.
- Central India and the Southern Peninsula saw increases of 8.6% and 9.3% respectively.
- East and northeast India received 17% less rain than typical.
Factors Influencing Monsoon Activity
- Western Disturbances: The active monsoon in northern India was attributed to western disturbances from the Mediterranean and storms from the Bay of Bengal.
- September Forecast: An increasing trend in September rainfall has been observed since 1980.
Challenges in Cloudburst Notification
- Data Limitations: A lack of meteorological stations in certain regions complicates categorizing cloudbursts.
- Satellite Limitations: While satellite imagery can warn of intense clouding, predicting a cloudburst remains difficult.
