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According to recent projections given to the Franklin County Emergency Management Agency, spring 2019 could usher in heavy flooding of several rivers in the county.

The National Weather Service (NWS) in St. Louis released information indicating that even average spring rainfall is expected to produce flooding in Franklin County due to the extreme amounts of snowfall to the north this winter.

Snowpack and soil moisture levels are unusually high in Minnesota, Wisconsin and Iowa. 

As that snow melts when the weather warms, much of the water ends up in the Mississippi and the rivers that feed into it.

With river levels already rising, the odds of significant flooding along the Mississippi and the rivers that feed it are high.

The NWS estimates as the snow melts, it will be like adding 2 to 8 inches of rain over Wisconsin, Minnesota and Iowa. 

This, coupled with expected precipitation, will then flood locations along the already swollen rivers. 

More than expected rainfall could cause additional flooding over the area, while less than expected rainfall could keep rivers from reaching expected crests.

Rain/Temps

In the near term, the Climate Prediction Center calls for precipitation to be most likely below normal in the six- to 10-day period, and near to above normal in the eight- to 14-day period.

Temperatures will most likely be below average in the next two weeks. The overall temperature outlook for March indicates a likelihood of colder than average temperatures.

As of Thursday, Feb. 27, the soil moisture for Franklin County was in the 95th percentile.

Meramec

The NWS says minor flood probabilities range from 9 to 13 percent above the seasonal average on the Meramec River.  

While the probabilities for moderate or greater flooding are also above normal for Illinois tributaries, those probabilities for moderate or greater flooding are closer to normal for most tributaries in Missouri.

Missouri

For the upper Mississippi, Missouri, and Illinois rivers, this spring flood outlook calls for a likelihood of moderate and major flooding.  

Along the Missouri River, there is a likelihood for moderate flooding at Jefferson City, Hermann, and St. Charles, though the likelihood is for minor flooding at Chamois, Gasconade, and Washington due to higher moderate flood thresholds at these gauges.  

Mississippi

For both the Mississippi and Illinois rivers, moderate flooding is at least 70 percent likely for all sites except LaGrange, Missouri, where the moderate flood threshold is a bit higher.