ST. LOUIS, MO. (AP) -- The National Weather Service is projecting a "high probability" of spring flooding along parts of the Mississippi and Missouri rivers and their tributaries.

Hydrologist Mark Fuchs today said several factors could lead to moderate or even major flooding in parts of Iowa, Illinois and Missouri.

Those factors include significant winter snow in northern states like North Dakota, South Dakota and Minnesota, and heavy rain last fall in parts of Missouri, Illinois and Iowa.

That water became trapped in the soil when the ground froze.

Once the ground thaws when the weather warms, significant runoff could cause rivers to rise.

Heavy rain over the weekend already has some rivers in Missouri above flood stage, but no major damage is reported.

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