Bhubaneswar: A low-pressure area formed over Strait of Malacca and adjoining South Andaman Sea at around 8.30 am on Saturday.
According to the India Meteorological Department (IMD), the system may move west-northwestwards and intensify into a depression over southeast Bay of Bengal around November 24. “Continuing to move west-northwestwards, it is very likely to intensify further over southwest Bay of Bengal during the subsequent 48 hours,” it added.
However, there is no clear indication that the low-pressure system will develop into a cyclonic storm.
Though the cold wave spell in Odisha has subsided under the impact of system leading to a rise in the night temperature, the IMD has issued no rainfall warning for the state. Dry weather is likely to prevail across Odisha till November 29 and no significant change in minimum temperature is expected over the next 6–7 days, it added.
What does weather models say?
There is a consensus among various models with respect to further intensification of the system into a depression over central parts of south Bay of Bengal. However, there is variation among various models on the time of genesis (when a depression with maximum sustained wind speed of 17–27 knots forms over the sea), with GFS group and ECMWF indicating development of depression around November 24 and NCUM group around November 27/28.
Models are also indicating further intensification and west-northwestwards movement of the system towards westcentral Bay of Bengal.
ECAIFS model is indicating genesis over southwest Bay of Bengal off South Sri Lanka coast around November 26 with initial northwards movement towards westcentral Bay of Bengal till November 30 and north-northeastwards movement towards northeast Bay of Bengal off South Bangladesh-Myanmar coasts till December 3. The guidance from ECAIFS is totally off the guidance from other models, the IMD said in its extended weather outlook.
What others have to say about the developing system?
On November 21, senior meteorologist Jason Nicholls said that the tropical low pressure will form in the southern Andaman Sea this weekend, and then gradually strengthen as it moves west-northwest. “The low will likely strengthen to at least a cyclonic storm before impacting eastern India late next week,” he posted on X.
Similarly, private forecaster Skymet predicted that the system may intensify significantly and track toward the south-central Bay of Bengal by November 25, with an uncertain path thereafter. With favourable oceanic and atmospheric conditions in place, the developing system could strengthen substantially, prompting heightened alerts across the entire east coast of India.
It further noted that historical November storms formed in this region often threaten Tamil Nadu, Andhra Pradesh, Odisha, West Bengal, or Bangladesh depending on steering currents. “Those which move in a west-northwesterly direction strike the North Tamil Nadu and adjoining South Andhra coast and emerge into the Arabian Sea, where they re-intensify. Tropical Storm Fengal in November last year followed this track and struck near Karaikal. Bay storms forming at more northerly latitudes move northwest and later recurve toward the northeast,” it added.
Though November storm is a rarity, Bulbul (November 2019) and Jawad (December 2021) have occurred in the post cyclone season.
Director of Centre for Environment and Climate (CEC) Sarat Sahu had also earlier said the low pressure may intensify into a deep depression or a cyclonic storm by November 26 and cross south Andhra Pradesh coast near Machilipatnam on November 27 night or the following day.
“However, the system is likely to weaken while crossing the coastline. Under its influence, widespread rains are expected in south Odisha and heavy showers may occur in south coastal districts from November 26 to 28,” he added.
