Patna, June 1: Patna Meteorological Centre today started giving its forecast on floods in river catchment areas of Bihar.

The body responsible for forecasting rainfall and floods in the rivers of Bihar at Patna Met Centre is known as flood meteorological office (FMO), which operates every year during monsoon.

“FMO, Patna, started operations from June 1 for forecasting floods during the upcoming monsoon. The office forecasts the amount of rainfall at various places near the river in the state, which have been divided into seven zones. The forecast of rainfall along various rivers, including Kosi, Kamala, Gandak, Bagmati and Punpun, are given to Central Water Commission (CWC), which, in turn, estimates the rise in the water level in these rivers,” said C.S. Patil, meteorological scientist at FMO.

“Then, the CWC informs the district administration about the amount of water that should be discharged through the floodgates in these rivers with respect to the rising water levels and accordingly, flood alerts are issued,” he added.

An FMO official told The Telegraph the forecast for flood is given by conducting a river-wise “quantitative precipitation forecast”, where the weather system around the river, including the circulation of air and moisture content, are analysed.

These elements are observed with respect to the general rainfall forecast and the existing water level in the river catchment and accordingly, a forecast is given for the rise in the water level of the rivers, the official added.

“Bihar is one of the most flood-prone states in the country. The FMO is highly effective in forecasting heavy rainfall received by the rivers in Bihar in case of a cyclone formation in the Bay of Bengal,” Patil said.

He said: “Besides, the office is also significant when the rivers in the state fall at the receiving end of weather changes in Nepal or Bengal. When such situations occur, inputs generated by the FMO are used by district authorities for iss-uing flood warnings and initiate contingency measures in the affected areas. The FMO will operate 24x7 from today till the end of this year’s monsoon.”

Department officials told The Telegraph that the FMO has given a forecast of 0.1mm to 10mm of rainfall in the Kosi belt and almost the same amount of rainfall in the Patna zone as well. “It has also been told that when the forecast rainfall is between 0.1mm and 10mm, the water-level in the rivers of that zone would rise by a metre.

A danger zone tag is given when an area is expected to receive rainfall between 51mm and 100mm, which would lead to a rise of water level by 5m and above.

A Patna Met official said monsoon is expected to arrive in Bihar around June 10.