GUWAHATI, Aug 13 � Monsoon rainfall over the NE region has by and large remained deficit till date. The monsoon thundershower activities over the region during the past one week have not been able to remove the deficiency significantly. Meanwhile, a strange weather system-related development has been noticed in the Bay of Bengal area which has been influencing the monsoon weather regime of the NE region.
H Pathak, the Deputy Director General of Meteorology (DDGM) of the Regional Meteorology Centre (RMC) here, told this newspaper this afternoon that the low pressure systems, which in the previous years used to form over the Bay of Bengal, have this year seemed to be forming over the coastal area most of the time.
These systems are also seen moving westward, away from the NE region, perhaps due to some peculiarities taking place in the global atmospheric circulation, he said.
This development needs further study linking it with the long-period global weather atmospheric circulation, the DDGM said. He also observed that weather has a functional relation with atmospheric circulation. And hence behaviour of atmospheric circulation has a pivotal role in causing precipitation (rain, hail, snowfall) over a region.
Today, the RMC has noticed formation of a well-marked low pressure system over Jharkhand and its adjoining areas in association with cyclonic circulation extending up to the mid-tropospheric level.
The system is tilting southward attaining a height that has extended up to 7.6 km above the main sea level. Under its influence, rainfall and thundershower may occur at many places over NE region during the next 24 hours, said the DDGM.
But finally, this system is likely to move in a west- north westerly direction, the DDGM said.
It needs mention here that Assam has recorded a deficit rainfall of 26 per cent between June 1, 2011 and today. It has received 756.6 mm of rainfall, against its normal of 1028.5 mm, during the period.
With 45 per cent, the deficit of Manipur in this regard is the highest. It is followed by Meghalaya with 44 per cent, Nagaland with 41 per cent, Mizoram with 28 per cent, Assam with 26 per cent and Tripura with 21 per cent, Pathak said.
However, the DDGM maintained that the 986.9 mm of rainfall [ (-) 9 per cent] recorded by Arunachal Pradesh during the period, against its normal of 1084.2 mm, is within the range of normal rainfall.