Tamil Nadu is heading for a dry weather as northeast monsoon enters its final phase.
The India Meteorological Department has predicted dry weather to prevail throughout the State, except for isolated light rain next week. Though there may be spill over of the monsoon in January, the department considers December 31 as the end of the northeast monsoon.
Tamil Nadu has recorded 44.4 cm of rainfall, which is 1% more than its seasonal average for northeast monsoon. Erode is among the few districts that have received heavy downpour, exceeding normal rainfall by 58%. Eight districts, including Tiruvarur, Thoothukudi and Ariyalur, have fallen short of their monsoon quota of rainfall by a minimum of 20%.
Most other districts received their normal rainfall. These include Chengalpattu, Chennai, Madurai and Ranipet. (IMD considers a deviation of 19% both on positive and negative side as normal). The IMD is likely to wait for a couple of no-rain days to declare the withdrawal of the northeast monsoon.
An IMD bulletin said that light to moderate easterlies prevailed over the region in the lower tropospheric levels and mist or haze may occur at one or two places over interior parts during early morning hours.
On Saturday, none of the weather stations recorded rain till 5.30 p.m. Kodaikanal recorded the lowest minimum temperature of 5.9 degree Celsius followed by 9.2 degree Celsius Coonoor and 15.15 degrees Celsius Namakkal. Suburbs of Chennai and interior parts experienced haze or mist during early morning hours.
S. Balachandran, Additional Director-General of Meteorology, Chennai, said various weather factors, including cloudless condition, high moisture content and calm winds led to such localised haze or mist cover in some areas.
On northeast monsoon performance, he said the global weather phenomenon — Madden Julian Oscillation — did not contribute much to the northeast monsoon rainfall. However, it was active during the southwest monsoon resulting in copious rain. Places such as Chennai recorded a good annual rainfall of 159 cm against the average figure of 140 cm due to a good southwest monsoon followed by a normal northeast monsoon.
However, a detailed analysis of various weather factors, including moisture variability, interaction of the weather systems with land area and easterly flow, need to be done for northeast monsoon’s performance, he said. There were 12 intense weather systems in the Bay of Bengal and the Arabian Sea this year compared to 10 weather systems formed last year, he added.