Bangkok, Sept. 23 -- Typhoon Ragasa, now in the East Sea, will cause heavy rain and flooding in northern, northeastern, central, and eastern Thailand this week, the country's Meteorological Department said. Bangkok Post quoted Director-General of the department Sugunyanee Yavinchan as saying that the influence of Typhoon Ragasa will strengthen monsoon troughs over the North, the upper Northeast, and the Gulf of Thailand from September 23 to 26. During the period, Sugunyanee said, heavy and persistent rain as well as flooding is possible in the North, Northeast, Central Plain including Greater Bangkok, and the East of Thailand. The Department of Disaster Prevention and Mitigation reported flooding in 16 provinces in the North, Northeast, C...