Yesterday was a relatively quiet day on the thunderstorms front over Tamil Nadu with subdued activity seen over South TN. Partially the very active west coast under the influence of the UAC over Arabian Sea is to be blamed for this. Many places in Kerala saw extreme rains during from Monday afternoon till the early morning hours of Tuesday with Kozhikode & Kannur seeing flooding in many parts of the city. Similarly good rains were reported in the Ghats as well over Tamil Nadu with Valaprai & surrounding areas coming under intense spell of rains that was reflected in the majestic Athirapally falls in full flow.
With two days left for the first half of October to come to an end the accumulated rainfall tally for the month stands at 110.8 mm for Tamil Nadu & Pondicherry sub division, this is little less than 2/3rd of the long term average for the month of October. In the meanwhile the western & Southern suburbs of Chennai came under some slow moving thunderstorms that were pretty much stationary for a long time over some of the places providing heavy rains in the bargain.
With two circulations on the either side things continue to look fluid over Peninsular India though the strong Westerlies due to the circulation over Arabian Sea means South TN may see another relatively subdued day of thunderstorms compared to North TN like yesterday. North TN continues to come under favorable wind instabilities in the form of LWD conditions stretching from the circulation off the coast of Arabian sea near Mangalore & all the way up to Bay of Bengal.
This is likely to trigger thunderstorms over many places of North & Northwest Interior Tamil Nadu with few places in line once again to record heavy rains under the influence of slow moving thunderstorms. The stretch between Chennai & Pondicherry may benefit from theses slow moving thunderstorms. Vellore, Tiruvannamalai, Chengalpattu, Villuppuram & adjoining parts of Pondicherry may come under good spell of rains once again today. Some parts of Villuppuram district has been having almost daily thunderstorms for the past few days & overall the district has been seeing an amazing few months since the poor June which saw very little rainfall activity this year.
In the meanwhile it will be another day of sudden burst of rains over a few places in Chennai & Suburbs though once again poor steering winds mean the storms may not move much & instead dumping heavy spells of rains for about 30 minutes or so. Few places could see rains continue for nearly an hour under favorable conditions. Once again it appears western suburbs & southern suburbs may benefit.