Washington, Sep 17 : Some five million peoples in parts of the southern US are under flash flood watches as Post-Tropical Cyclone Nicholas lingers over the central Gulf Coast, local media reported. Nicholas, which made landfall in Texas as a Category 1 hurricane on Tuesday morning, soaked parts of Louisiana, Mississippi, Alabama and the Florida Panhandle as it weakened to a tropical depression, Xinhua news agency quoted a CNN report as saying on Thursday. Nicholas became a post-tropical cyclone Thursday morning, the National Weather Service (NWS) Weather Prediction Center said. An additional 2 to 4 inches of rain may fall in the region through Friday, with some areas at risk of seeing 12 inches, the Weather Prediction Center said. Flash flood watches are in effect when weather conditions are conducive to flash flooding, but it doesn't necessarily mean that flash flooding will occur, according to NWS. Nicholas, the Atlantic hurricane season's 14th named storm, formed in the Gulf of Mexico earlier on Sunday. A 14th named storm in the Atlantic basin, the total number of storms in an average season, typically does not form until November 18. /IANS