Chennai: The India Meteorological Department (IMD) has issued an Orange Alert for Chennai, Tiruvallur, and Ranipet districts, forecasting heavy to very
heavy rainfall in the range of 12 to 20 cm within a 24-hour period on October 27. This extreme weather event is being driven by a developing system in the Bay of Bengal, which is expected to intensify into Cyclone Montha. The system will intensify into a depression by October 25 and a deep depression by October 26, leading to heavy to very heavy rainfall in Tamil Nadu, Kerala, Andhra Pradesh, and Odisha from October 25 to 29.
Cyclone Montha meaning
The name ‘Montha’, meaning ‘fragrant flower’, was provided by Thailand. While the cyclone is currently projected to track towards Andhra Pradesh, its peripheral influence is set to unleash significant rainfall across northern Tamil Nadu, with the heaviest downpours concentrated in the alerted districts.
Cyclone Montha Trajectory to Dictate Rainfall Intensity in Chennai
A critical uncertainty remains regarding the exact intensity of rainfall in Chennai, hinging on the cyclone’s final path. The IMD’s alert prepares for the worst-case scenario. However, independent meteorologists like Pradeep John have noted a key variable.
In a social media post, John stated, “If this low-pressure area moves north towards the sea, Chennai may not receive very heavy rains.” He elaborated that if the storm moves away from the Tamil Nadu coast towards Andhra Pradesh, Chennai would likely experience only moderate rainfall instead of the forecasted deluge. This scenario would also mean no widespread rains for the rest of Tamil Nadu, with only isolated showers in Kerala, Kanyakumari, and the Nilgiris.
TN Rains: District-Wise Forecast and Timeline
The IMD has outlined a clear progression of the weather system over the coming days. The low-pressure area is set to intensify into a depression today, then into a deep depression with wind gusts up to 56 kmph, before maturing into Cyclone Montha with wind speeds of 65-75 kmph over the Bay of Bengal by October 27.
This intensification will drive a multi-day rain event. Heavy rains are expected to commence today in Cuddalore, Villupuram, Chengalpattu, and Puducherry. The activity will spread northwards tomorrow, impacting Chennai, Kanchipuram, Tiruvallur, and Ranipet. The peak is expected on October 27, with heavy to very heavy rain in the Orange Alert districts and heavy rain in Chengalpattu, Kanchipuram, and Vellore. The rains will begin to subside on October 28, likely persisting only in Tiruvallur and Ranipet.
Chennai weather today
For Chennai today, the forecast is for partly cloudy skies with light to moderate rain and thunderstorms, with temperatures ranging from 24°C to 30°C.
