CHENNAI: Even as the India Meteorological Department (IMD) has forecast below-normal rainfall across the country during August and the latter half of the southwest monsoon season, Tamil Nadu is expected to witness a comparatively favourable rainfall pattern, particularly in the coastal districts.
Moderate rainfall is expected over Chennai and neighbouring districts during the weekend, with light to moderate evening thunderstorms forecast for the city.
According to the IMD’s seasonal outlook, the northern coastal and southern coastal parts of Tamil Nadu are likely to receive normal to above-normal rainfall during August, while northern interior and southern interior TN are expected to receive normal rainfall. The Western Ghats districts, however, are likely to record below-normal rainfall.
The outlook comes even as parts of southern Tamil Nadu have begun August with intense rainfall. Data from the Regional Meteorological Centre (RMC), Chennai, showed Nalumukku in Tirunelveli recorded 294.4 mm during a 24-hour period ending 8.30 am on Saturday -- the highest rainfall in Tamil Nadu. Oothu received 270 mm and Kakkachi, 190 mm, while several stations in Kanniyakumari, Theni, Coimbatore and Tenkasi recorded rainfall ranging between 80 mm and 140 mm. Of the 620 rain gauge stations monitored across the state, 160 recorded measurable rainfall.
Thunderstorms accompanied by lightning and gusty winds reaching 40-50 kmph are likely across Tamil Nadu until August 3. The met department has also projected that maximum temperatures during August will remain near normal to slightly above normal across most parts of Tamil Nadu and Puducherry, while minimum temperatures are expected to remain normal to above normal, leading to warm and humid nights in many areas.
V R Durai, head of the Regional Weather Forecasting Centre, said the national climate outlook indicates that moderate El Nino conditions over the equatorial Pacific are expected to strengthen further during the remaining southwest monsoon season, a development that typically suppresses monsoon rainfall. Neutral Indian Ocean Dipole (IOD) conditions, however, are expected to persist through August, and some international climate models indicate a positive IOD may develop during September, potentially offsetting part of El Nino’s adverse influence, he added.