The SWM rainfall distribution in Coimbatore district has always been a disputed one. As far as I am concerned, inclusion of Valparai taluk and inclusion of heavy rainfall regions in Valparai taluk continues to boost rainfall figures during SWM period. The SWM rainfall for Coimbatore district would be around 189.6mm only; whereas the Rainfall of Valparai taluk for SWM period is around 3800.0mm. That is nearly 20 times. The NORMAL in SWM rainfall distribution statement for Coimbatore district does not contain heavy rainfall regions in Valparai Taluk. Valparai is the only taluk situated in the hills of average elevation about 1100 -1800 meter. But this heavy rainfall statistics is very important and vital indicative of monsoon activity in Kerala and TN.
By including Valparai taluk's rainfall the new NORMAL for Coimbatore district can be deduced with the use of existing normals. (Area weighted) Once it is deduced then the question of 'LARGE EXCESS' rainfall in Coimbatore district will NOT occur.
or
If taluk wise rainfall distribution is considered then the "vitiating distribution" will NOT at all arise.