It’s the third week of May and there is still no respite from drought, heat wave and soaring temperature, nor is it likely to be in the coming weeks if the met department is to be believed. For as per IMD’s predictions, monsoons in Kerala would be delayed by a week from its earlier scheduled date of June 1.

The delay of rainfall in Kerala is significant as the southwest monsoon over the southern region hints at arrival of monsoon in others parts of the country as well.

The India Meteorological Department [IMD] forecast for monsoon onset over Kerala has been made with a model error of plus or minus of four days. The model uses six predictors: minimum temperatures over north-west 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 OLR over the south-west Pacific region. Reports quoted an IMD official as saying that out of the six predictors used in the model, five indicated delayed monsoon over Kerala.

The department further said that conditions were becoming favourable for the onset of southwest monsoon over Nicobar Islands, south Andaman Sea and parts of south Bay of Bengal on around May 17 and advancement over the entire Andaman Sea close to its normal date. It, however, added that past data suggested of no link between dates of monsoon advance over the Andaman Sea either with those of monsoon onset over Kerala or with the seasonal monsoon rainfall over the country.

IMD said that its forecast of onset of monsoon for the past 11 years (2005-2015), except 2015, have been correct. To give an example, it said that in 2014, the onset date was predicted at June 5 while monsoon arrived on June 6. Similarly, the previous year (2013), IMD predicted monsoon on June 3 while the rains arrived on June 1.