...Heavy rainfall and flooding threat late this week and into the
weekend...
The combination of a slow moving and stalling cold front along
with the Tropical Depression Gordon are expected to bring
widespread rainfall to central and eastern Missouri as well as
west central and southwest Illinois Thursday morning through this
weekend. Heavy rainfall is possible, particularly across northeast
Missouri and west central Illinois.
Present indications suggest the highest rainfall rates and
greatest rainfall amounts will occur Saturday and Saturday night as
Tropical Depression Gordon passes through the region and interacts
with the stalled front. Areas along and just north of I-70 appear
to be under the greatest threat for heavy rainfall and flooding at
this time given the current projected track of Gordon. 4 to 6
inches of rainfall is forecast from today through Sunday in these
areas. A flash flood threat could materialize if persistent high
rainfall rates develop over any one location.
Additionally, minor river flooding is already forecast to begin
later this week on the Mississippi River north of St. Louis as a
result of heavy rain that has fallen across the Upper Mississippi
River Basin during the last 7 to 10 days. The additional rainfall
expected from today through this weekend could result in moderate
or even major flood levels and additional downstream flooding. It
could also result in flooding on other tributaries of the
Mississippi River including the Salt, Fabius, and Cuivre Rivers.
Minor to moderate flooding is also likely along the Missouri
River. Fortunately, there is not as much water upstream in the
Missouri River Basin, so the flooding threat is less on the
Missouri than on the Mississippi.
Please note that the forecast information provided in this
outlook is highly dependent on the track of Tropical Depression
Gordon. Confidence in that forecast has increased, but some
uncertainty remains and the greatest threat area could end up
shifting north or south depending on the eventual track and speed
of the system.
People in central and eastern Missouri and western Illinois
should stay abreast of the latest forecasts and be prepared for
heavy rainfall and flooding Thursday into the weekend.