ST. LOUIS — Concerns of early spring flooding in Missouri eased Wednesday as the Mississippi River crested north of St. Louis and the Missouri River began to fall, but forecasters said the risk of flooding remains high.
Above-normal temperatures have been quickly melting snow in the Upper Midwest and swelling rivers, while cool and damp weather in Missouri has kept the state's soil saturated and unable to absorb more moisture. Whether that translates into significant flooding depends on how much, where and how fast it rains.
It's impossible to predict rain accurately beyond 10 days, said National Weather Service meteorologist Ben Miller. Much of Missouri has a chance for rain or snow this weekend. But next week is expected to be dry.
"The soils are so saturated, any precipitation is going to run into the river system," Miller said. "It won't take as much rain to produce a flood."
But he said precipitation hasn't been excessive so far this year, and a year of normal rainfall won't produce the flooding seen a few years ago.
The St. Louis area was experiencing minor flooding, affecting mostly agricultural ground, secondary roads and outbuildings. Hannibal, in northeast Missouri, along with Quincy and Chester in Illinois, have moderate river flooding, he said.
The Mississippi River in most places in Missouri will stay above flood stage for seven to 10 days, with possible flooding of low-lying ground.
But it doesn't come close to the record flooding of 1993, when whole communities were deluged, and 2008, when levees in Canton and Clarksville were threatened and Foley and Winfield, north of St. Louis, were flooded. More than 120 homes were damaged.
Those two flood years were preceded by a wet fall, above-average snowpack and summer thunderstorms.
He said the recent rise in Missouri's two great rivers is from snow melting in the Upper Midwest. Most of the snow that empties into the Mississippi and Missouri River basins has melted. Most of the snow still on the ground will flow into the Red River.
State Climatologist Pat Guinan said this week that during a recent trip across northern Missouri, he observed saturated soils; full farm ponds, streams and rivers; and farm fields that resembled bogs.
Sunshine and warm winds from the south usually begin to evaporate standing water, but the state hasn't had many days with warm temperatures, he said, adding that Missouri's wettest months — May and June — are still to come.
"There's just no place for the water to go but downstream," he said.
The city of Hannibal, which is on the Mississippi River, put up two of its five downtown floodgates last week as a precaution. The river hasn't spilled its banks, and it crested at 20.4 feet on Tuesday, 4 feet above flood stage. All five gates would be needed if the river rises to 21.5 feet, emergency management director John Hark said Wednesday.
The river is expected to drop this week to 19 feet, where it's expected to stay for seven days. Hark said none of Missouri's river towns were reporting flooding, but each was taking precautions.
"I'm on alert," Hark said. "I go with the flow, whatever the river does. If you don't stay ahead of the Mississippi River, it will sneak up on you."