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The flood forecast for the Rock River at Moline was 14.7 feet as of 9:30 p.m. Wednesday, down slightly from earlier in the day.

Flood stage is 12 feet.

The 14.7-foot number is lower that the 15-foot crest that had been forecast earlier Wednesday by the National Weather Services’ North Central River Forecast Center in Chanhassen, Minnesota. 

Despite the expected crest being lowered, there remains the danger of ice jams along the river that could cause the waters to rapidly rise, said National Weather Service meteorologist Andy Ervin. 

Ervin saidt th crest was lowered because there is now less water flowing out of the Green River into the Rock River. 

"It's a few thousand feet per second that was in the original forecast that is now out of the forecast," he said. 

However, if anyone sees an ice jam on the river they should contact authorities immediately, Ervin said. 

"Ice that is moving is not an ice jam," he said. "Ice that is not moving needs to be reported."

Earlier in the day, meteorologist Tim Gross of the National Weather Service, Davenport, said there was not a lot of confidence that river would have reached the 15-foot mark. 

It's the  ice on the river that has made predictions difficult, Gross said.

For instance, Illinois 78 near Prophetstown, Illinois, was closed part of the day Wednesday due to flooding. “That’s because of the ice," he said. "Right around Prophetstown, there are sheets of ice.”

The Rock at Moline was at 11.6 feet as of 8:30 p.m. Wednesday. It was expected to reach its 12-foot flood stage about midnight, and reach near 13 feet about noon today.

However, all that is subject to change.

“It all depends on when the ice comes down the river," Gross said. “Abrupt fluctuations are possible due to changing river ice conditions.”

Simply, he said, when the ice moves from one site upstream, the river level there drops. As the ice proceeds downstream, the river levels at those sites rise.

Gross said the River Forecast Center takes into account precipitation forecasts for the next 48 hours, so the snow and rain that is expected today already is calculated into the river level forecasts.

But more rain is expected Saturday, Gross said. If the area gets too much rain, that could create other problems on the Rock River as well as push the Mississippi River at Lock & Dam 15, Rock Island, closer to its 13-foot action stage.

Forecasters will have a better idea Friday morning of how the system due in early Saturday is likely to track.

Gross added that while there is frost in the ground down to about a foot, the top eight inches of soils in the region are showing signs of no frost, which has helped recharge the moisture of the upper layers of the soil. However, that area of the soil also is saturated, so too much rain will runoff into the rivers and streams, causing them to rise.