The southwest monsoon arrived in Kerala on Tuesday, three days ahead of its normal date of onset, the India Meteorological Department (IMD) said. The IMD's announcement is in line with its prediction of May 29 as this year's scheduled date of onset.

"The southwest monsoon has further advanced into remaining parts of southeast Arabian Sea, Comorin-Maldives area, entire Lakshadweep, most parts of Kerala, some parts of Tamil Nadu and some more parts of southwest, central and northeast Bay of Bengal," the IMD said. Kerala has recorded widespread rainfall over the past three to four days and the 14 rainfall monitoring stations have reported more than 60% rainfall since May 25. Since early hours of Tuesday, westerly winds have also strengthened over the south Arabian Sea.

Ponnani in Malappuram district recorded the heaviest rainfall of the day, at 16 cm.

The IMD said conditions were favourable for the monsoon to advance, during the next 48 hours, to remaining parts of Kerala, parts of coastal and south interior Karnataka and some parts of the northeastern states. The IMD, in an evening bulletin, also noted the persisting well-marked low pressure area over southeast Arabian Sea and adjoining east-central Arabian Sea off the north Kerala-Karnataka coast. The Indian National Centre for Ocean Information Services has forecast high waves in the range of 3 to 3.9 metres till May 31 along the coast of southern Tamil Nadu, from Kolachal to Kilakarai.

The southwest monsoon normally sets in over Kerala around June 1 and advances northward, covering the entire country by July 15. The IMD has forecast normal monsoon rainfall (96% to 104% of the Long Period Average) this year. In its long range forecast, issued in April, the IMD said the rainfall this year was likely to be 97% of the LPA with a model error of +/- 5%.

The Kerala State Disaster Management Authority said squally weather and rough sea conditions were likely to prevail over the Kerala-Karnataka coast, Lakshadweep and the Comorin area.