The weekend has seen dry conditions dominate Chennai Weather with pretty much most of Tamil Nadu giving company to Chennai in this dry spell. Interestingly if one were to analyze the conditions even those days when Chennai does not receive any rains Peninsular India sees thunderstorms develop in many places under convective conditions. The last couple of days have seen even the convective thunderstorms also vanish from interior TN and adjoining South AP & Karnataka.
It is not a coincidence that this dry spell has come at the same time when we are seeing fairly gusty conditions across the state as a prelude to the month of “Aadi” which goes with the old saying “ஆடி காற்றில் அம்மி கல்லும் பறக்கும்”. The month of Aadi is the time when Southwest Monsoon is at its peak which is also indicated by the other festivals like “Aadi Perukku” etc relating to the possible majestic flow in Cauvery on account of heavy rains in the Kodagu region. If one were to look at the thunderstorm pattern the East Coast of India stands a better chance in terms of rainfall possibility when the offshore trough is weak in the West Coast and the Southwest Monsoon goes through a break conditions when the monsoon trough is closer to the foothills of Himalayas.
In the current context there exists a fairly strong offshore trough in the West Coast running from Maharashtra to Kerala along the coast. Additionally if one were to look at the Model Outputs parts of Central Tamil Nadu is likely to see surface wind gust above 50 kms in many places particularly those places that fall under the East of Palghat Pass, a stretch of about 30 kms, where the Western Ghats is conspicuous by its absence. Similarly North Tamil Nadu & the interior places of NW TN is also likely to see gusty conditions continue today as well.
The precipitation expectation from models pretty much confirms the hold dry conditions hold over Chennai Weather and other places of Tamil Nadu and adjoining East Coast. While West Coast is likely to see rains at many places with few places in Kerala & Karnataka likely to see moderate to heavy rains. The heavier rains in West Coast are likely to happen around interior Maharashtra under the influence of the Upper Air Cyclonic Circulation that is currently near West MP region. Places like Nashik has already got more than 15 cms last night and is likely to see the rains continue today as well.