JOIN USMet upgrades forecast to 98% rain
The India Meteorological Department (IMD) on Tuesday maintained that the Southwest monsoon would be better than expected in 2017 as the country is likely to receive 98% of the average rainfall between June and September.
The Met department also released the forecast for four regions, out of which Central India is likely to receive 100% of its average rainfall and Southern Peninsula will get 99% rainfall. India’s average rainfall calculated over 50 years is 890 mm.
The forecast for Northeast and Northwest India is 96% rainfall. Each forecast comes with a model error of 8% on either side. The Southwest monsoon is the lifeline for lakhs of farmers who grow summer crops like paddy, pulses, oilseeds, cotton and coarse cereals.
“Monsoon did not move for a few days because of a low-pressure zone over the Arabian Sea. From Tuesday, it began moving. We hope the monsoon would reach Bengaluru in another 2-3 days and arrive in Mumbai by June 13-14,” IMD Director General K J Ramesh told DH.
The June forecast is actually an upgrade from the prediction issued by the IMD six weeks ago in which the department had claimed 96% of average rainfall for the season. Both forecasts have an error margin of 4%.
The upward revision stems from the fact that ENSO (El Nino Southern Oscillation) neutral conditions are likely to prevail for the remaining part of 2017. El Nino is an unusual warming of the Pacific Ocean, leading to massive weather disruption all over the world. An El Nino year is generally associated with a poor monsoon.
“We expect monsoon distribution to be very good. The monsoon is likely to reach Bihar, Jharkhand and West Bengal by June 13-14,” said Ramesh.
According to the forecast, there is 50% probability of the Southwest monsoon being normal, while there is 28% chance of it becoming below normal, in which the rainfall will vary between 90% and 96% of the average. There are very slim chances of monsoon becoming “deficient” or “excess”.
The monthly rainfall over the country as a whole is likely to be 96% of the average in July and 99% in August with a model error of 9%, the IMD stated.
The IMD forecast is based on a statistical forecasting model that uses six climatic parameters. In addition, inputs from an in-house dynamical model are also used to derive the forecast.
DH News Service