Scattered rainfall may continue over the State and Puducherry till July 5. The warm, humid days may end with thunderstorms in many districts and the Meteorological department forecasts heavy rain in a few districts.
Thunderstorms with heavy rain are set to roll through nine districts, including Salem, Dharmapuri, Theni, Madurai and Villupuram on Friday and a few more places in other parts of the State. Puducherry may experience light to moderate rain.
Officials of the Meteorological Department said the same weather pattern of scattered rain that may be heavy in one or two places of a few districts may continue till July 5.
S. Balachandran, Deputy Director General of Meteorology, Chennai said whenever the southwest monsoon is weak in other parts of the country, thunderstorms pick up pace in the southern region. Westerly winds continue to prevail and trigger convective activity.
On Thursday, places like Tirupattur (4 cm), Kodaikanal (2 cm) and Kancheepuram (1 cm) were among some of the weather stations that received rain till 5.30 p.m. During the weekend, heavy rain may cover parts of north Tamil Nadu.
Officials of the Meteorological Department noted that a trough line from interior Karnataka to the Comorin sea across Tamil Nadu persists at 0.9 km above the mean sea level. This, too, influenced thunderstorms over the State.
Though the maximum temperature in Chennai was 34.4 degree Celsius, which is two degree Celsius below normal on Thursday, the high humidity level kept the coastal city warm.
Chennai, which has been missing rain for two days now, too has chances of thunderstorms lashing some areas till Saturday. The maximum temperature would be around 36 degree Celsius for two days.
The Meteorological Department has now started posting monthly weather summary on its website in both English and Tamil.
N. Puviarasan, Director, Area Cyclone Warning Centre Regional Meteorological Centre, Chennai, said details about global weather conditions and also weather systems that prevailed over the State and rainfall would be updated in the monthly summary.
Upper Bhavani (22 cm) and Avalanche (21 cm) in Nilgiris district recorded the heaviest rainfall in June. Tamil Nadu and Puducherry together recorded 21% excess rainfall in June.
However, officials noted that the State gets more rainfall from southwest monsoon during August and September. “We are also planning to update on the comparison of weather model forecasts and realised rainfall,” Mr.Puviarasan added.
Meanwhile, the department on Thursday predicted that below normal to normal rainfall may occur in some parts of the State in July.