IMD forecasts heavy rain in Nilgiris, Coimbatore, Theni from July 30
Synopsis
Tamil Nadu is caught in a split weather pattern: the Western Ghats — including Nilgiris, Coimbatore, and Theni — are set for heavy rain from 30 July, while coastal and plains districts face temperatures up to 4°C above normal. The IMD's seven-day outlook underscores how the southwest monsoon's terrain interaction can bring flood risk and heat stress to the same state simultaneously.
Key Takeaways
The IMD has forecast moderate rain with thunderstorms across Western Ghats districts in Tamil Nadu for the next seven days from 29 July .
Isolated heavy rainfall is expected in the Nilgiris on 30 July , and in Coimbatore , Nilgiris , and Theni on 31 July and 1 August .
Maximum temperatures in Tamil Nadu and Puducherry may rise up to 4 degrees Celsius above normal on 29–30 July .
Chennai is expected to see partly cloudy skies with the maximum temperature likely to exceed 39 degrees Celsius .
Residents — especially in hill districts — have been advised to monitor local forecasts as rainfall intensity may vary.
The India Meteorological Department (IMD) has forecast moderate rainfall with thunderstorms across Western Ghats districts in Tamil Nadu over the next seven days, with isolated heavy showers expected in parts of the Nilgiris, Coimbatore, and Theni districts from 30 July onwards. The warning was issued by the Regional Meteorological Centre (RMC), Chennai, on 29 July.
Rainfall Forecast for Western Ghats Districts
A weak trough persisting in the lower levels of the atmosphere over the Tamil Nadu coastal region is the primary driver of the weather activity. The system is expected to trigger moderate rain with thunderstorms across Western Ghats districts beginning 29 July.
Isolated places in the Nilgiris district are likely to receive heavy rainfall on 30 July. Heavy rain at one or two places in Coimbatore, Nilgiris, and Theni districts is forecast for both 31 July and 1 August. The IMD noted that the rainfall is expected to benefit the hilly regions of the state.
Above-Normal Temperatures Across Tamil Nadu
While the hill districts brace for showers, the plains and coastal areas face a contrasting picture. Maximum temperatures across Tamil Nadu and Puducherry could rise by up to 4 degrees Celsius above the seasonal average on 29 and 30 July, resulting in hot and humid conditions across much of the state.
This dual weather pattern — heavy rain in the ghats alongside intense heat in the lowlands — reflects the influence of the prevailing atmospheric trough, which channels moisture toward elevated terrain while leaving coastal and inland plains dry and sweltering.
Chennai Weather Outlook
For Chennai, the RMC has forecast partly cloudy skies with the possibility of rain in a few parts of the city. No significant rainfall has been predicted for the capital. The maximum temperature in Chennai is expected to exceed approximately 39 degrees Celsius, sustaining the heat stress that has gripped the city in recent days.
Residents have been advised to take precautions against heat stress, stay adequately hydrated, and avoid prolonged exposure to the sun during peak afternoon hours.
Public Advisory and What to Watch
The weather department has urged residents — particularly those in the hill districts — to stay updated on local forecasts, as rainfall intensity could vary significantly over the coming days. Notably, this kind of split weather pattern, with the Western Ghats receiving precipitation while coastal Tamil Nadu bakes, is characteristic of the southwest monsoon's interaction with the region's topography.
Authorities in Nilgiris, Coimbatore, and Theni are expected to remain on alert as the forecast period progresses into the first days of August.
Point of View
Bringing life-giving rain to hill districts while the plains — including the state capital — endure punishing heat. A 4-degree-above-normal temperature spike alongside heavy-rain alerts in the same state is not a contradiction; it is the southwest monsoon's structural signature in peninsular India. What deserves closer attention is whether district administrations in Nilgiris, Coimbatore, and Theni — areas historically vulnerable to landslides and flash floods during concentrated rainfall — have pre-positioned response resources. Heat-health advisories for Chennai are welcome, but enforcement and outreach to vulnerable populations remain the real test.
NationPress
29 Jul 2026
Frequently Asked Questions
Which districts in Tamil Nadu are likely to receive heavy rain this week?
The IMD has forecast heavy rainfall in isolated places in the Nilgiris district on 30 July, and at one or two places in Coimbatore, Nilgiris, and Theni districts on 31 July and 1 August. Moderate rain with thunderstorms is expected across all Western Ghats districts for seven days from 29 July.
Why is Tamil Nadu experiencing both heavy rain and high temperatures simultaneously?
A weak atmospheric trough over the Tamil Nadu coast is channelling moisture toward the Western Ghats, triggering rain in elevated districts. The plains and coastal areas, however, remain largely dry and are seeing temperatures up to 4 degrees Celsius above seasonal averages — a pattern typical of the southwest monsoon's interaction with the region's terrain.
What is the weather forecast for Chennai on 29 July?
Chennai is expected to see partly cloudy skies with the possibility of rain in a few parts of the city, but no significant rainfall has been forecast. The maximum temperature is likely to exceed approximately 39 degrees Celsius, and residents have been advised to guard against heat stress.
How much above normal could temperatures rise in Tamil Nadu?
According to the IMD, maximum temperatures over Tamil Nadu and Puducherry could rise by up to 4 degrees Celsius above the seasonal average on 29 and 30 July, leading to hot and humid conditions particularly in the plains and coastal districts.
What precautions has the IMD advised for Tamil Nadu residents?
The IMD has advised residents to stay adequately hydrated, avoid prolonged sun exposure during peak afternoon hours, and take precautions against heat stress. Those in hill districts such as Nilgiris, Coimbatore, and Theni have been urged to track local forecasts closely as rainfall intensity may vary over the coming days.
