The trend of Isolated Rains in Tamil Nadu continued last evening as well. Kaatupakkam, about 15 kms to the South of Tambaram recorded about 16 mm rains from the evening thunderstorms. Further down south Mailam in Villupuram district recorded more than 3 cms rains yesterday. A few places in the delta region as well like Manalmedu recorded moderate spells of rains.
As Bay of Bengal gets ready to churn out the next set of monsoon disturbances these disturbances are likely to trigger the rainy days in Peninsular India. With tropical disturbance likely to evolve at two different locations we will have to see over the next 24 – 48 hours which one evolves stronger based on which the rainfall pattern could change for South India during the weekend. Nevertheless the rainfall prospects are likely to improve from tomorrow with weekend promising to provide a spell or two of good rains for places like Chennai. All set for a slightly more widespread pattern of Rains in Tamil Nadu compared to the extremely isolated thunderstorms that have been developing over the last few days.
While the Upper Air Cyclonic Circulation has created the necessary synoptic conditions it has also changed a key element in the equation, availability of moisture, most of August we have seen poor moisture at upper levels resulting in weak thunderstorms developing primarily aided by the sea breeze incursion with no atmospheric support to talk off. The next couple of days though the moisture availability is shown to increase and provide moderately conducive conditions for the development of thunderstorm which could make the thunderstorms more intense and possibly also become more wide spread.
Chennai is likely to see cloudy conditions in the morning which could give away to fairly clear skies by early afternoon resulting in a hot day with day time max of around 36 degrees. Sea breeze is expected to move in around 2 PM which could trigger some thunderstorms to the Southwest of the city but the better prospects for Chennai in terms of rains will be later in the night as remnant thunderstorms move towards the coast which could intensify under unstable conditions around the coast, as things stand midnight / early morning rains look more possible for Chennai.