Arabian Sea ‘low’ pips Bay twin to ramp up as depression
Heavy rainfall seen in Tamil Nadu
The well-marked low-pressure area over south-east Arabian Sea has prevailed in a battle of wits with a counterpart system over the Bay of Bengal, having concentrated into a depression, India Meteorological Department (IMD) said this (Wednesday) morning.
The depression lay at about 630 km west-southwest of Aminidivi (Lakshadweep) and 1,020 km south-west of Panjim (Goa), an IMD updated issued at 5.30 am said. It is likely to move slowly nearly north-northwestwards until tomorrow (Thursday).
Extended stay
Global models are hinting at several days of its continued stay over warm waters (28-29℃ ) that supports further intensification. Short-to-medium outlook of the IMD too indicates scope for its calibrated strengthening on a track parallel to West Coast.
The US Joint Typhoon Warning Centre said the system is poorly organised with embedded flaring convection to its north-west. Environmental analysis revealed marginally favorable conditions, with warm sea surface temperatures and good window effect on top offset by moderate to high (37-46 km/hr) easterly wind shear.
Restrictive factors
Increasing values of vertical wind shear (change in wind speed and direction with height) does not allow the storm tower to build properly. Global deterministic models show its slow and gradual development over several days. The other well-marked ‘low’ over south-west Bay of Bengal off north Sri Lanka coast moved northwestwards and currently lay off Tamil Nadu coast.
Proximity to Lanka and Tamil Nadu coasts may be inhibiting pace of its development, but IMD maintains that, while moving northwestwards, there is a possibility for intensification into a depression over south-west and adjoining west-central Bay off north Tamil Nadu and south Andhra Pradesh coasts later today. Thereafter, it may move across north Tamil Nadu, Puducherry and south Andhra Pradesh coasts by midmorning of tomorrow (Thursday).
Published on October 22, 2025
