CHENNAI, June 9: The south-west monsoon advanced into Kerala, Lakshadweep and parts of Tamil Nadu today, after a delay of eight days.The special weather bulletin issued by the meteorological office here said Kerala and Lakshadweep received rainfall at many places.The monsoon is likely to advance further into the southern parts of Andhra Pradesh and Karnataka during the next 48 hours.During the next 24 hours, rain or thundershowers will occur at many places over Kerala, Lakshadweep, coastal Karnataka and at a few places over interior Tamil Nadu and at one or two places over the remaining parts of the region, the bulletin said.While parts of Kerala have received heavy rainfall today, the coastal Karnataka, north-east Karnataka and south-east Karnataka have received heavy pre-monsoon showers, it added.Though the westerly winds during the last week of May partially affected the advancement of the south-west monsoon resulting delay, the bulletin said a scientific reply could not be given for the exact cause of the delay immediately.The bulletin further said that this year the pre-monsoon showers were well distributed over the country. This conditions considerably reduced the heat wave normally prevalent during this season.