Northeast monsoon is likely to set in over Tamil Nadu within three days. The India Meteorological Department (IMD) on Thursday announced that southwest monsoon had retreated from the region on Wednesday, paving the way for northeast monsoon to arrive.
S. Balachandran, Additional Director-General of Meteorology, Chennai, said, “We are expecting northeast monsoon to arrive within three days. But the initial phase of the monsoon will be weak with less rainfall activity because of the presence of the weather systems in both the Bay of Bengal and the Arabian Sea. The State will experience less rainfall for a week.”
The Regional Meteorological Centre, Chennai, has forecast that two weather disturbances would intensify into depressions in the next few days.
While a cyclonic circulation is likely to become a depression over the Arabian Sea around October 21, another cyclonic circulation over the southeast Bay of Bengal would intensify as a low pressure area by Saturday and would gain in strength to become a depression over the westcentral Bay of Bengal around October 23.
The arrival of the northeast monsoon this year, too, would be around the normal date of October 20. A standard deviation of seven days is considered normal.
An increase in rainfall in the State would depend on the movement and strength of the weather disturbances. The monsoon would arrive with scattered rain over the State and the trend would continue till October 25.
Recalling the IMD’s long-range forecast for the season, Mr. Balachandran said the State would experience a normal rainfall. The entire south peninsular region, including south interior Karnataka and Rayalaseema, is expected to receive 29 cm-37 cm of rain during the season.
The southwest monsoon yielded 8% excess rainfall in Tamil Nadu and 74% surplus rainfall in Chennai. The IMD has predicted light rain in some areas of Chennai till Saturday.