Deep depression in the making may spark stormy conditions over Bay
A well-marked low-pressure over the Bay of Bengal (right) appeared better organised over its twin over the north-east Arabian Sea (left) on Wednesday even as the Bay system may ramp up as a deep depression.
| Photo Credit:
www.tropicaltidbits.com
The India Meteorological Department (IMD) expects near-stormy conditions to develop over the Bay of Bengal with an overnight low-pressure area deepening to being ‘well-marked,’ on Wednesday; it is now under watch for intensification twice over into a depression and a deep depression over the next two days.
A deep depression ranks next only to a full-fledged cyclone in strength and intensity, with the ongoing monsoon transition period from south-west (June-September) to north-east (October-December), and changes in associated upper level dynamics known to develop favourable conditions for storms to evolve over the Bay. For now, however, IMD expects the system to stop just short of ramping up as a cyclone.
Off the AP-Odisha coasts
The causative well-marked ‘low’ was parked over the west-central Bay (off the Andhra Pradesh-Odisha coasts) on Wednesday. It is likely to continue to move north-northwestwards and concentrate into a depression over the same region during the night, into Thursday morning. It will stick to the same track, and rustle up more strength to intensify as a deep depression and cross the south Odisha-north Andhra Pradesh coasts on Friday morning.
Seas stay active
The 24 hours ending Wednesday morning have already seen heavy to very heavy rain over East India across Assam and Meghalaya; Nagaland, Manipur, Mizoram and Tripura; the hills of West Bengal and Sikkim; as also over West Uttar Pradesh in North-West India. Heavy rain lashed the Andaman and Nicobar Islands; Arunachal Pradesh; West Bengal; Jharkhand; East Uttar Pradesh in the east; and Haryana-Chandigarh-Delhi; West Madhya Pradesh in the north-west; and coastal Karnataka in the south in view of active seas on both sides of the peninsula.
Extremely heavy rain
Isolated extremely heavy rainfall is likely over Odisha on Thursday, as the well-marked ‘low’ hums away. Isolated very heavy rainfall is likely over West Bengal, Odisha, and Chhattisgarh, both on Thursday and Friday; Jharkhand on Friday; the hills of West Bengal and Sikkim on Friday and Saturday; and over Bihar for three days from Friday.
Buzz in Arabian Sea
Meanwhile, another well-marked ‘low’ bubbling with convection and clouds was located overnight over the north-east Arabian Sea and the adjoining Saurashtra coast on Wednesday. It continued to beat forecasts of ramping up as a depression and appears to be biding its time. The IMD said it is likely to move nearly westwards and intensify through Wednesday night into Thursday morning. But, unlike the twin over the Bay, it would be headed out into the sea, moving away from the coast into the high seas progressively.
Helpful circulations
A ‘soaker’ trough runs diagonally across from a well-marked ‘low’ over the north-east Arabian Sea and the adjoining Saurashtra coast to south-west Uttar Pradesh, cutting through East Rajasthan, presaging rainfall along its track. Helpful upper air cyclonic circulations hung over South Bangladesh; central Assam; north-east Assam; and north-east Rajasthan, while a fresh western disturbance is likely to affect North-West India from Saturday, enhancing rainfall prospects over parts of North-West India.
Published on October 1, 2025
