Chennai: The Regional Meteorological Centre (RMC) in Chennai has forecast moderate rainfall accompanied by thunderstorms across several parts of Tamil Nadu and Puducherry on Tuesday, November 4.

According to the RMC bulletin, while the northeast monsoon has officially set in, its full impact is yet to be felt due to weak easterly winds and the lingering influence of westerlies.

Rainfall recorded in the 24 hours ending Monday morning showed Malai in Ranipet district, Sethupattu in Tiruvannamalai district, and Valathi in Villupuram district each receiving 3 cm of rain.

A low-pressure area over the east-central Bay of Bengal and adjoining Myanmar coast continues to persist in the same region and is expected to move towards the Bangladesh and Myanmar coasts over the next 24 hours.

The RMC further noted that moderate thunderstorms with lightning are likely over isolated areas in Tamil Nadu and Puducherry on Tuesday and Wednesday, while light rain is expected to continue until 11 November.

Maximum temperatures in some districts could rise by up to 4°C above normal, the forecast added. For Chennai and its suburbs, the sky is likely to remain partly cloudy, with light to moderate showers and thunder expected at a few locations later in the day. Daytime temperatures are expected to remain high due to limited moisture inflow from the Bay of Bengal.

Despite the official onset of the northeast monsoon, meteorologists observed that westerly winds remain dominant and the easterly flow has yet to strengthen, resulting in patchy and delayed rainfall across many areas.

The prevailing hot afternoons have triggered convective rainfall during the evenings and nights, a pattern experts say is likely to persist until around November 12. After that, the easterlies are expected to intensify, strengthening the northeast monsoon across Tamil Nadu.

Meanwhile, a tropical storm named Kalmaegi has formed over the South China Sea near the Philippines and is moving towards Thailand. Officials clarified that the system will not have any significant impact on the northeast monsoon over Tamil Nadu.

IANS