Chennai Weather Update: Thunderstorms and Moderate Rain Expected This Week

Chennai’s weather today is dominated by thunderstorms and overcast skies, with temperatures ranging from 26 °C to 29 °C. Misty conditions persist under high humidity of 89% and northeast winds at 6 km/h. The IMD forecasts an 84% chance of rain, with moderate showers likely from afternoon into evening, and isolated heavy spells in some coastal localities.​

The IMD weather forecast for Chennai predicts steady rainfall through October 18, accompanied by thunder, lightning, and gusty winds of up to 40 km/h. City authorities have issued a Chennai IMD alert, warning of potential waterlogging in low-lying areas and advising residents to avoid venturing out during intense storms. Drivers should plan routes carefully, as heavy rain may reduce visibility and create puddles on major thoroughfares.​

Weekly Weather Update

• October 15–16: Thunderstorms with moderate to heavy rain, highs of 26–30 °C, 84–85% precipitation probability, winds of 9–12 km/h from the northeast.​

• October 17–18: Overcast skies and intermittent storms, highs of 29–31 °C, lows of 26–27 °C, with up to 27 mm of rainfall expected on October 18.​

• October 19–21: Isolated thunderstorms continue, daytime temperatures stabilize at 29–30 °C, nighttime lows at 26–27 °C, and rain chances range from 49–75%.​

High humidity levels of 74–78% will create sultry conditions throughout the week. October typically brings over 20 rainy days to Chennai, with total monthly precipitation between 113 mm and 259 mm. Beachgoers are advised to avoid sea swimming during storm periods due to rough waves and strong currents.​

Chennai Air Quality

Chennai’s AQI stands at 95 (Moderate), with PM2.5 at 32 µg/m³ and PM10 at 45 µg/m³. Other pollutant levels include carbon monoxide at 458 ppb, sulfur dioxide at 3 ppb, nitrogen dioxide at 8 ppb, and ozone at 6 ppb. Recent rainfall has improved air quality from yesterday’s AQI of 81, as precipitation helps remove particulate matter from the air. However, individuals with respiratory or heart conditions should limit prolonged outdoor activities when humidity is high and air quality dips.​

The ongoing northeast monsoon pattern can cause sudden weather shifts. Residents should stay informed through the IMD’s official channels, monitor local news for updated Chennai weather updates, and prepare for possible disruptions such as delayed flights, train rescheduling, and temporary school closures due to flooding risks. Continuous monitoring of the Chennai AQI is recommended, particularly in densely populated neighbourhoods with heavy traffic, where pollution can accumulate despite rainfall.