Reminding 2015 memories to many people, not only among the bloggers but also common people, Chennai & suburbs saw an extreme spell of rains during the wee hours of Sunday which brought localized flooding to many areas as Chennai Nungambakkam saw the heaviest 24 hour rainfall since 2015 recording 21 cms for the 24 hours ending 8:30 AM, 7th November. While the southern parts of the city & southern suburbs did not get this deluge spell most parts of the central areas along with Northern suburbs bore the brunt which brought bulk of the rains between midnight & daybreak.
The good news though is we might see a slight reduction in the rains for Chennai and suburbs today which could allow draining the flood waters in some of the affected localities. But one should keep in mind the soil moisture is fairly high due to what has been a very good year of rains for most parts of TN. This could mean every little spell of rains will aggravate the localized flooding instance due to the inability of soil to absorb the water. Rather it is likely to increase the surface runoff thereby amplifying the localized flooding risk. It is for this reason this week is crucial as we might have a spell of nonstop rains as the expected disturbance comes closer to TN Coast in a couple of days time.
The Upper Air Cyclonic Circulation that triggered the rains for the past couple of days over Chennai & Surroundings is now drifted south in what could be an interesting development that is likely to impact on how things pan out for the next few days. It appears the UAC off TN coast may transfer its energy to the UAC moving in a NW direction from Southeast Bay thereby creating an LPA out of it somewhere between Sri Lanka & Andaman Islands. It remains to be seen if this development is likely to enhance the rainfall probability over Coastal TN.
Meanwhile due to the shift of the UAC today we may see heavier rains over Delta Districts & South TN areas with few places coming under very heavy spell of rains at times. Similarly due to the moisture migration across the interior areas we might see few places along the Western Ghats also come under intense spell of rains through trapped moisture. The heaviest spell of rains may happen south of Pondicherry today with Chennai & suburbs getting a slight breather today though morning hours may see moderate to heavy spell of rains over a few areas