A slow-moving frontal boundary is setting the stage for a significant flood threat this weekend across parts of the Upper Mississippi River Valley, with the FOX Forecast Center warning that multiple rounds of heavy rainfall could lead to dangerous flash flooding .

Forecasters are most concerned for communities between Des Moines, Iowa and Chicago , where hourly rainfall rates could reach 1-3 inches with an expected weekend total approaching 9 inches of precipitation in some areas.

Given recent rounds of showers and thunderstorms in the Midwest, NOAA's Weather Prediction Center has issued a Level 3 out of 4 on its excessive rainfall risk gauge for parts of southern Wisconsin , northwest Illinois and portions of Iowa.

"This is going to be one of the things we’re watching most closely here

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