(CNN) — A Missouri woman was killed in the state's flash flooding Thursday as inclement weather hammers several states in what forecasters predict will be a particularly nasty storm season.
As rescue teams were performing 18 "swift water rescues" in McDonald County, Missouri, Thursday morning, the woman thought to be in her 60s was driving over a bridge when she was caught up in "rapidly rising waters," said Gregg Sweeten, the county's emergency management director.
It was the second weather-related death in the state this week. Elijah Lee, 4, died Monday after 6 inches of rain fell on Pulaski County, about 140 miles southwest of St. Louis. The boy was found in a vehicle swept up in the floodwaters that caught the community along Mitchell Creek off guard, said Missouri Highway Patrol spokesman Sgt. Dan Crain.
His mother, Jessica Lee, 23, of Waynesville is missing, and authorities and volunteers are using canine units in their search for her.
Back in McDonald County, Sweeten said he was hopeful the Elk River, which runs through this county located on the Arkansas state line, about 80 miles southwest of Springfield, Missouri, would crest late Thursday night.
South of the capital, Jefferson City, Interstate 44 was shut down because of high water. It's since been reopened.
Forecasters warn that areas along the Gasconade River could see record water levels, and widespread flooding is expected to continue in Missouri and Kansas into the weekend.
Southern Missouri has witnessed widespread flash flooding as parts of 12 Midwestern and Eastern states experienced some sort of flood watch or warning Thursday.
Nashville, Tennessee, was one of the hardest hit, as parts of the city saw as many as 8 inches of rain overnight and in the morning. Another 1 to 3 inches were expected Thursday afternoon and evening, according to forecasters.
A flash flood emergency had been issued for much of the city earlier Thursday, and a flash flood warning remains in place until the afternoon.
Atlanta also is under a flash flood warning until Thursday evening, and flooding is possible across much of Georgia, South Carolina and North Carolina.
The weather struck as the National Oceanic and Atmospheric Administration revised its preseason hurricane forecast to say there is a 70% chance of an "above-normal" Atlantic hurricane season.
Where a normal season might bring six hurricanes, three of them above Category 3 or higher, this season could bring as many nine hurricanes, and five of them could be major, the NOAA says.
The NOAA says the season, which runs through November, could yield as many as 19 named storms.