New Delhi, May 19: The monsoon is expected to hit Kerala on May 29—three days ahead of its normal date of onset June 1 on India’s mainland.
“The south-west monsoon is expected to set in over Kerala on May 29 with a model error of ± 4 days,” the India Meteorological Department (IMD) said in its forecast on Friday.
Monsoon sets over Kerala on June 1 with a standard deviation of about seven days and during its four-month stay gives rains to more than 66 per cent of the country’s agricultural lands.
Its arrival over the Indian mainland marks the start of the rainy season. As it progresses northward, relief from scorching summer temperatures is experienced over the areas.
The IMD has been issuing operational forecasts for the date of monsoon onset over Kerala from 2005 onwards. An indigenously developed state of the art statistical model with a model error of ± 4 days is used for this purpose.
The six predictors used in the models are minimum temperatures over Northwest India, pre-monsoon rainfall peak over south Peninsula, outgoing Long wave Radiation (OLR) over south China Sea, lower tropospheric zonal wind over southeast Indian ocean, upper tropospheric zonal wind over the east equatorial Indian Ocean and outgoing Long wave Radiation (OLR) over the south-west Pacific region.
