Northeast monsoon likely by Oct 15; Tamil Nadu rain, gusty winds forecast today
Synopsis
Weather observer Pradeep John has predicted the northeast monsoon could arrive around 15 October, even as the IMD flags moderate rain and 40-50 kmph winds for Tamil Nadu today. With an atmospheric circulation moving towards the region, Tamil Nadu may be on the cusp of its most important rainfall season — but an official onset call is still awaited.
Key Takeaways
Weather observer Pradeep John has predicted the northeast monsoon could begin around Thursday, 16 October , subject to official IMD confirmation.
IMD has forecast moderate rain, thunder, lightning and gusty winds across The Nilgiris, Coimbatore, Erode, Madurai, Salem, Kanniyakumari, Tirunelveli, Thoothukudi, Tenkasi, Sivaganga and Tiruppur .
Wind speeds in affected districts could reach 40 to 50 kmph .
Chennai will see partly cloudy skies with a maximum of 35-36°C and minimum of 26-27°C .
Northern interior Tamil Nadu may see temperatures 2 to 3 degrees Celsius above normal despite rainfall activity elsewhere.
Puducherry and Karaikal are also likely to receive light rain with thunder on Monday.
The India Meteorological Department (IMD) has forecast moderate rain, thunderstorms, and gusty winds across several districts of Tamil Nadu on Monday, 13 October 2025, even as weather observer Pradeep John has predicted the northeast monsoon could make its onset around Thursday, 16 October. The dual developments signal a significant shift in the region's weather pattern as the season transitions.
Districts Under Rain Watch
According to the IMD bulletin, moderate rainfall is expected in The Nilgiris, Coimbatore, Erode, Madurai and Salem during the day. A broader belt of the state has been placed under a forecast for light to moderate rain accompanied by thunder, lightning, and strong winds.
The districts covered under this wider alert include Kanniyakumari, Tirunelveli, Thoothukudi, Tenkasi, Sivaganga and Tiruppur, in addition to those already mentioned. Wind speeds in affected areas could reach 40 to 50 kilometres per hour, the bulletin noted. Puducherry and Karaikal are also likely to receive light rain with thunder and lightning at some places.
Chennai Outlook and Temperature Trends
Chennai is expected to see partly cloudy skies on Monday. The city's maximum temperature is forecast to range between 35 and 36 degrees Celsius, while the minimum is likely to settle between 26 and 27 degrees Celsius.
Despite the prospects of rain, maximum temperatures at some locations in northern interior Tamil Nadu could remain two to three degrees Celsius above normal. Temperatures in the rest of the state, Puducherry and Karaikal are expected to remain close to seasonal norms, the department said.
Northeast Monsoon Onset: What Pradeep John Said
Weather observer Pradeep John, a member of the El Nino Impact Study Group, has indicated that the northeast monsoon could begin around next Thursday. In a post on X, John noted that an atmospheric circulation moving towards the region adjoining Tamil Nadu was likely to create favourable conditions for the monsoon's onset.
Notably, this remains a prediction and not an officially confirmed onset date from the IMD. The northeast monsoon, which is the primary rainfall season for Tamil Nadu and other parts of peninsular India, typically arrives in early-to-mid October. This year's anticipated onset aligns broadly with historical averages.
What to Watch
The combination of pre-monsoon thunderstorm activity and the imminent northeast monsoon onset means residents across Tamil Nadu, Puducherry and Karaikal should brace for a dynamic week ahead. An official IMD confirmation of the monsoon's onset, expected in the coming days, will be the key development to watch. Coastal and low-lying areas, in particular, could see intensified rainfall once the seasonal circulation establishes itself.
Point of View
But the gap between an observer's call and an official IMD onset declaration matters — particularly for farmers, disaster managers and water-resource planners in Tamil Nadu who depend on certified onset dates to mobilise. The broader pattern here is the northeast monsoon's increasing year-to-year variability: an early or delayed onset by even a week can significantly alter reservoir inflows and kharif harvests across peninsular India. Mainstream coverage tends to reduce this to a weather bulletin; the real story is how Tamil Nadu's water-stressed districts will absorb what could be an uneven onset after a below-normal southwest monsoon season.
NationPress
12 Oct 2026
Frequently Asked Questions
When is the northeast monsoon expected to arrive in Tamil Nadu in 2025?
Weather observer Pradeep John has predicted the northeast monsoon could begin around Thursday, 16 October, based on an atmospheric circulation moving towards the region adjoining Tamil Nadu. However, this is a prediction and not an officially confirmed onset date from the IMD.
Which Tamil Nadu districts are on rain alert today?
The IMD has forecast moderate rain with thunder, lightning and strong winds in The Nilgiris, Coimbatore, Erode, Madurai, Salem, Kanniyakumari, Tirunelveli, Thoothukudi, Tenkasi, Sivaganga and Tiruppur. Wind speeds could reach 40 to 50 kmph in affected areas.
What is the weather forecast for Chennai today?
Chennai is expected to have partly cloudy skies on Monday. The maximum temperature is forecast between 35 and 36 degrees Celsius, and the minimum between 26 and 27 degrees Celsius, with light rain possible.
Why is the northeast monsoon important for Tamil Nadu?
The northeast monsoon is Tamil Nadu's primary rainfall season, typically contributing over 48% of the state's annual precipitation. Its onset, usually in early-to-mid October, is critical for reservoir storage, agriculture and groundwater recharge across the region.
Who is Pradeep John and why does his forecast matter?
Pradeep John is a weather observer and member of the El Nino Impact Study Group who is widely followed for seasonal monsoon predictions in southern India. His forecast for the northeast monsoon's onset around 15-16 October is based on atmospheric circulation analysis, though it awaits official IMD confirmation.
