By Saibal Gupta Kolkata, Oct 3 : With the monsoon likely to take another week before starting its withdrawal process, the districts of Gangetic West Bengal have received 31 per cent more rainfall this year with the city recording nearly double (96 per cent) rainfall than normal, making it the wettest September in this decade. In general, North Bengal receives more rain than South Bengal but this year the process was reversed with Gangetic West Bengal recording surplus rainfall of nearly 31 per cent and North Bengal and Sikkim receiving 9 per cent deficit rainfall (between June 1 and September 30). However, the met department has predicted heavy rainfall in North Bengal in the next couple of days and it is expected that this will reduce the deficit considerably. Interestingly enough, according to the Meteorological Department though the state witnessed a comparatively dry August this year with 34 per cent deficit rainfall, the excessive rainfall in September has helped in covering the deficit and having surplus rainfall in the state. In September, the state received 39 per cent excess, while Gangetic Bengal had a surplus of 80 per cent rain. North Bengal, which usually receives more rain than the south, has been dry this year. Along with Sikkim, North Bengal has a 9 per cent rain deficit, down from a 40 per cent deficit in north Bengal and Sikkim last month. As far as Kolkata is concerned, the city received nearly 96 per cent more rainfall in September this year. The normal rain count for Kolkata in September is 318 mm. This year, it received 613 mm, said the Met Office. The city has rarely had such a wet September in recent years, said the weathermen. "Two rain-triggering systems -- one a cyclonic circulation on September 20 and the other a low-pressure front that struck on Wednesday -- generated heavy rain that took the count above the normal mark. Both triggered a night-long deluge, and the city received rain in excess of 100 mm each day. We have rarely come across such a wet September in recent years," a senior official of the weather department said. The city had received 142 mm rain on September 20, while the rain-count touched 105 mm on September 22. September 20 turned out to be the wettest September day in Kolkata since September 25, 2007, when the city had received 174.4 mm rain. "Cumulatively the city received around 250 mm rain in these two days. But the rain didn't really stop in between. Local thunderstorms and clouds floating in from the Bay of Bengal continued to trigger consistent drizzles. We hardly had a sunny day in the last fortnight," the official added. The excess rain coupled with the release of water from the Damodar Valley Corporation have led to a flood situation in seven districts of South Bengal. Several districts including Howrah, Hooghly, Birbhum and Bankura, areas of Purba and Paschim Medinipur districts besides the industrial areas of Asansol and Durgapur in Paschim Barddhaman district have been flooded because of this. /IANS