Isolated extremely heavy rain is forecast on Thursday for Tamil Nadu, Puducherry & Karaikal and south coastal Andhra Pradesh & Yanam on Wednesday and over south interior Karnataka as India Meteorological Department (IMD) brought the Bay of Bengal under watch for a monsoon depression on a day when an away-going predecessor over west-central Arabian Sea moved closer to Oman coast.
The nine hours ending Monday evening saw heavy to very heavy rain at isolated places over Kavali (coastal Andhra Pradesh & Yanam) while it was moderate over Nellore (5 cm). Elsewhere, rainfall of varying amounts was reported from most places over Tamil Nadu, Puducherry & Karaikal and Coastal Andhra Pradesh & Yanam and at many places over Kerala & Mahe.
Expanded could cover
Satellite pictures on Tuesday morning showed expanded cloud cover signalling light to moderate to heavy showers over south Andhra Pradesh, Telangana, south interior Karnataka, Rayalaseema, coastal Andhra Pradesh, Tamil Nadu and Kerala bounded by Miryalguda, Kurnool, Bellari, Shivamogga, Nellore, Angola Chennai, Ambur, Mysore and Kozhikode. Cities such as Mysuru, Bengaluru, Tirupati and Proddatur have been brought under moderate to intense cloud cover.
Intense cloud cover was seen hanging over coast and adjoining north Tamil Nadu coast around Chennai and extending to Ponneri, Satyavedu, Arakkonam, Tambaram, Kanchipuram, Chengalpattu, Kalpakkam, Cheyur, Chetput, Gingee, Polur, Arni, Tiruvethipuram, Arcot, Vellore, Tirupati, Srikalahasti, Nayudupet, Gudur, Nellore, Kadapa and Rayachoti in neighbouring coastal Andra Pradesh and interior. Heavier clouds threaten the Tamil Nadu coast as they waited turn from their base over the seas.
Isolated very heavy rain is forecast for Coastal Andhra Pradesh & Yanam on Tuesday; over Tamil Nadu, Puducherry & Karaikal; Kerala & Mahe; south interior Karnataka; and Rayalaseema for three days until Thursday; and Coastal Karnataka on Thursday. It will be Isolated heavy over Kerala & Mahe on Friday; Coastal Andhra Pradesh & Yanam; Coastal Karnataka; and South Interior Karnataka until Thursday; north interior Karnataka on Wednesday and Thursday; and Lakshadweep on Thursday and Friday.
S-W monsoon exiting land
Meanwhile, the south-west monsoon is just 24 hours away from exiting the land and yielding the ground clear for monsoon in reverse (north-east monsoon). Easterly and northeasterly wind regime may establish over the south peninsula and south and adjoining central Bay, heralding the October-to- December rains initially over the south-east peninsula (coast of Tamil Nadu and adjoining south Andhra Pradesh).
Depression soon over Bay
As if on cue, Monday’s low pressure area over south-east Bay of Bengal moved west-north-west and intensified lay as a ‘well-marked low’ over the central parts of the south Bay on Tuesday morning. It is likely to intensify into a depression and move towards north Tamil Nadu, Puducherry and adjoining south Andhra Pradesh coasts during next two days, the IMD said. Another cyclonic circulation lay over south-west Bay and adjoining Tamil Nadu coast. On the Arabian Sea side, a weather-making trough ran down from the centre of prevailing depression to the Comorin across south Kerala.
Widespread rain forecast
In an outlook for the south peninsula, the IMD predicted fairly widespread to widespread to moderate rain for Kerala & Mahe; Lakshadweep; Puducherry & Karaikal; Kerala & Mahe; Coastal Karnataka and Rayalaseema during the week; over Tamil Nadu, Puducherry & Karaikal for next three days; and over north interior Karnataka, Coastal Andhra Pradesh & Yanam and South Interior Karnataka for four days. It will be scattered to fairly widespread to moderate over Tamil Nadu, Puducherry & Karaikal for four days; north interior Karnataka and south interior Karnataka for three days; and isolated to scattered to moderate over Telangana during the week.