Thiruvananthapuram, Oct. 27
A cyclonic circulation to the immediate south of the peninsular tip and a large-amplitude westerly trough combined overnight to ramp up rainfall across the peninsula on Friday.
The cyclonic circulation materialised so close to the coast that the cloudiness started penetrating the mainland right away, said Dr K.J. Ramesh of the Department of Science and Technology.
This happened even as a mid-latitude westerly system waded its way in, and impacted the circulatory features to the far south.
The result was that associated cloudiness got strewn way in a north-northeast direction, bringing regions from Kanyakumari to coastal Andhra Pradesh under rain cover. The resident trough of low over the southwest Bay of Bengal, off the Tamil Nadu coast, too chipped in.
The precipitation was widely spread across Kerala, especially in Tamil Nadu. The rain bands extended in to coastal Karnataka.
The National Centre for Medium Range Weather Forecasting said the ongoing rainfall activity over the southern peninsula would intensify further over the next three to four days. Isolated heavy to very heavy rainfall is likely over Tamil Nadu, Puducherry, Kerala and Lakshadweep. Fairly widespread rainfall is likely over Andaman and Nicobar Islands, Tamil Nadu, Puduchery, Kerala, south coastal Andhra Pradesh and Lakshadweep.
CYCLONE NOT RULED OUTMr Jim Andrews of AccuWeather.com agreed that there was hint of a tropical depression near Sri Lanka and the southern tip of India. Numerical forecast models were still suggesting that it could deepen towards the west into a tropical cyclone. A weak northeast monsoon seems to have set itself up north of the Inter-Tropical Convergence Zone of `low' (within which the circulation lies). This would certainly favour rainy weather, possibly over the five to seven-day period.