The India Meteorological Department on Tuesday said conditions are becoming favourable for the advance of the southwest monsoon into parts of the south Bay of Bengal, the Andaman Sea and the Andaman & Nicobar Islands towards the end of this week.
The development comes even as large parts of north and central India continue to battle severe heatwave conditions.
In a press release, the IMD said, “Conditions are becoming favourable for the advance of southwest monsoon likely over parts of south Bay of Bengal, Andaman Sea and Andaman & Nicobar Islands towards the end of this week.”
The weather agency also said a low-pressure area over the southwest Bay of Bengal remained active on Tuesday morning and could intensify further over the next 48 hours.
“The low-pressure area over southwest Bay of Bengal lay over the same region at 8:30 a.m. of today, the 12th May 2026, with the associated cyclonic circulation extending up to 4.5 km above mean sea level. It is likely to become more marked during the next 48 hours,” the IMD said.
Southwest Monsoon May Reach Andaman Region Soon
The southwest monsoon typically reaches the Andaman and Nicobar Islands around May 20 before gradually advancing towards mainland India.
Kerala usually witnesses the onset of the monsoon around June 1, marking the official beginning of India’s four-month rainy season, which continues until September.
Earlier this month, the IMD had projected the possibility of below-average rainfall during the 2026 monsoon season due to emerging El Niño conditions.
According to the department, the equatorial Pacific region is gradually transitioning from ENSO-neutral conditions towards an El Niño phase, which is often associated with weaker monsoon rainfall in India.
Heatwave Conditions To Continue In North And Central India
While monsoon conditions are developing over southern regions, the IMD warned that intense heatwave conditions are expected to continue across several parts of the country.
Severe heatwave conditions are likely to persist in isolated areas of Rajasthan, particularly West Rajasthan, over the next six to seven days.
Heatwave conditions are also expected in parts of:
- East Rajasthan
- Madhya Pradesh
- Gujarat
- Maharashtra
The weather department has also forecast a gradual rise in daytime temperatures across northwest and central India over the coming week. However, Gujarat may see slight relief after May 14, with temperatures expected to dip marginally.
Heavy Rainfall Forecast In Southern And Northeastern States
Alongside the heatwave warning, the IMD has also predicted widespread thunderstorm activity and heavy rainfall across several southern and northeastern states.
Heavy rain is likely over:
- Tamil Nadu
- Kerala
- Puducherry and Karaikal
- South interior Karnataka
Thunderstorms accompanied by lightning and gusty winds are also expected across Telangana, coastal Andhra Pradesh, Karnataka and Lakshadweep over the next few days.
In the northeastern region, widespread rainfall activity is likely between May 12 and May 18 across:
- Assam
- Meghalaya
- Arunachal Pradesh
- Nagaland
- Manipur
- Mizoram
- Tripura
The IMD has specifically warned of isolated very heavy rainfall in Assam and Meghalaya between May 13 and May 17.