Issued by NWS North Central River Forecast Center
AGUS73 KMSR 261739
HYDROMETEOROLOGICAL FORECAST DISCUSSION
NWS NORTH CENTRAL RIVER FORECAST CENTER TWIN CITIES/CHANHASSEN MN
1138 AM CST THU NOV 26 2015
In the last 24 hours...a complex system has begun to impact the
region...bringing a mixture of precipitation types across the
NCRFC area. Gulf moisture flowing northward ahead of an arctic
cold front brought rain across the eastern two-thirds of the NCRFC
area. Parts of northeastern Illinois and southwestern lower
Michigan saw a quarter to a half an inch of rain...while other
areas in Iowa...southern and eastern Wisconsin...Illinois and
Michigan saw a couple tenths or less. Scattered light snow was
observed across portions of northern Minnesota and north
Dakota...and snow was beginning to develop behind the front in
Minnesota and northwestern Iowa.
In the next 24 hours...mixed precipitation...including ice and
sleet...are forecast on the cold side of the front...as well as
some accumulating snow as the front pushes eastward. The
heaviest precipitation totals are forecast along an axis from
southwestern Iowa...northeastward through southern
Wisconsin...with rain totals through Friday morning as high as
1.75 inches. Snow accumulations of 1 to 4 inches are possible from
northwestern Iowa through southeastern Minnesota...and in to
central and northeastern Wisconsin by Friday morning. Most of
lower Michigan is expected to see precipitation...in the form of
rain...with widespread totals of one half to an inch or more by
Rain is expected to continue through the weekend in the southern
portion of the NCRFC...with much of Missouri and southern
Illinois expected to see as much as 4 inches of precipitation in
the next 5 days.
With forecast precipitation for the next two days being used
in the river forecast model... numerous locations in Iowa...
Missouri... Illinois... Michigan... and Wisconsin... are expected
to exceed bankfull conditions. A handful of locations are
currently forecast to exceed flood stage... however these
forecasts are driven by forecast rainfall on saturated soils...
and changes in rainfall amounts and placement will cause these
river forecasts to need adjustment.
With saturated soils and little vegetation... the forecast
rainfall is generating a lot of surface runoff in the river
model. Changes in rainfall amounts of as little as a quarter of
an inch will change the amount of surface runoff generated...
and will affect the ultimate forecasts for the rivers.
The Mississippi River at St.Louis has been above ten feet since
the 18th... and is expected to stay above ten feet for at least
the next two weeks... possibly rising above 20 feet next week...
depending on actual rainfall over the next few days.
Current flows at St.Louis are running over two times higher than
what is typical for this time of year.
The Mississippi River headwaters region... tributaries in Iowa...
Missouri... Wisconsin... and Illinois... are running high for
late November. The United States Geological Survey shows
flows above the 90th percentile for most of the gaging locations
in these states. For more information on specific locations see:
The United States Drought Monitor still shows some small areas
of abnormally dry to moderate drought in North Dakota...
northwestern Minnesota... and Michigan. For more information on
specific locations see:
For additional and more in-depth information concerning river
forecasts...precipitation and all hydrometeorological information
in the NCRFC area of responsibility...please refer to the NCRFC
web page at: http://www.weather.gov/ncrfc
Emergency Call Back List: LNE...BAC...JDT
If no response from this list... call the DOH...SCH or HIC.