Tamil Nadu, which is reeling under a severe drought and therefore desperately awaiting a spell of rain, may have to wait for some more time for a clear picture on the benefits of the southwest monsoon to emerge.
Though the State falls under the rain shadow region, the monsoon contributes to an average of 32 cm, which accounts for 30% of the State’s annual average rainfall.
‘Have to wait’
“We have to wait for the implications of the early onset of the monsoon over Tamil Nadu,” said S.B. Thampi, Deputy Director General of Meteorology, Regional Meteorological Centre, Chennai.
The State has received 8 cm of rainfall so far this season from March 1, which is 15% less than its average rainfall. The early onset of the southwest monsoon over the Andaman and Nicobar Islands may influence the setting in of monsoon over Kerala.
Normally, the monsoon sets in over Kerala during the first week of June and spreads over to other parts of southern peninsular region.
The monsoon is active between June and September.
Mr. Thampi said the strengthening of southwesterlywinds and persistent cloud cover had helped early onset of the monsoon over the Andaman and Nicobar Islands. “We expect this to accelerate setting in of monsoon over Kerala a week ahead,” he said.
However, there is no direct correlation between early or late setting in of monsoon and rainfall pattern/volume of rainfall. “We expect the southwest monsoon rainfall to be 96% of the long period average this year. As El-Nino may not be strong, we expect the monsoon to end with normal rainfall,” he said.
