Flood Potential Outlook
Issued by NWS Duluth, MN

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PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE Duluth MN
1025 AM CST Thu Feb 13 2025

...Spring Flood and Water Resources Outlook...

This outlook covers NE Minnesota and NW Wisconsin for river forecast
points on the headwaters of the Mississippi, Chippewa, St. Croix,
and Rainy Rivers.


...Current Conditions...

Most river basins have a normal to below normal amount of water in
the snowpack.  Some areas along the North Shore have normal to above
normal snowwater. Drought conditions persist in the region due to
well below normal precipitation since July.  Fall rains slightly
improved the drought condition in November.  Precipitation since
October 1st. Is near normal.  The ground is deeply frozen due to
frequent cold snaps and shallow snow depth.  This is a key factor in
this Spring`s flood potential.  With continued cold temperatures
expect frost depths to increase.  Rivers are ice covered which could
be a factor in ice jam flooding.


...Climate Outlook...

Through February 21st expect some additional snow on Friday February
14th mainly across central Minnesota, NW Wisconsin and points to the
south.  The Climate Prediction Center`s 2 week outlooks show below
normal temperatures and favor drier than normal conditions.  The
outlook for March, April and May show an equal chance of both
temperatures and precipitation being above or below normal.

...Spring Flood Risk...

The Spring flood risk is normal to below normal and highest in
Northeast Minnesota. Precipitation and rate of melt through early
spring while the ground is still frozen is one of the most important
flood risk factors. Frost depths of 30 inches or deeper are common
which is much deeper than normal.  The presence of deep frost and its
affect on spring runoff are not explicity accounted for in the
probabiliy of flooding.

In Table 1 below...the current (CS) and historical (HS) or normal
probabilities of exceeding minor...moderate...and major flood stages
are listed for the valid time period.

CS values indicate the probability of reaching a flood category
based on current conditions.

HS values indicate the probability of reaching a flood category
based on historical or normal conditions.

When the value of CS is more than HS...the probability of
exceeding that level is higher than normal. When the value of CS is
less than HS...the probability of exceeding that level is lower
than normal.


...Table 1--Probabilities for minor...moderate and major flooding...
                    Valid Period:  02/17/2025 - 05/18/2025

                                       :    Current and Historical
                                       :     Chances of Exceeding
                                       :       Flood Categories
                                       :      as a Percentage (%)
                      Categorical      :
                   Flood Stages (FT)   :   Minor    Moderate   Major
Location           Minor   Mod   Major :  CS   HS   CS   HS   CS   HS
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Prairie River
Taconite            10.0   12.0   13.0 :  <5   <5   <5   <5   <5   <5
:Mississippi River
Aitkin              13.0   15.0   18.0 :  16   49   <5   28   <5    7
Fort Ripley         10.5   12.5   26.0 :  18   39   <5   15   <5   <5
:St. Croix River
Danbury              7.0    8.5   10.0 :  <5    8   <5   <5   <5   <5
:Snake River
Pine City            9.0   10.0   11.0 :   6    8   <5    5   <5   <5
:St. Louis River
Scanlon             10.5   11.0   13.0 :  <5    5   <5   <5   <5   <5
:Knife River
Near Two Harbors    33.0   34.0   36.0 :  <5   <5   <5   <5   <5   <5
:Nemadji River
South of Superior   24.0   26.0   28.0 :  <5   <5   <5   <5   <5   <5
:Tyler Forks
Near Mellen          9.0   10.0   12.0 :  24   34   14   24   <5    5
:Bad River
Near Odanah         16.0   18.0   20.0 :  <5   <5   <5   <5   <5   <5
At Odanah            8.5    9.5   10.5 :  <5    6   <5   <5   <5   <5
:South Kawishiwi River
Ely                  6.5    7.5    8.5 :   7   23   <5    9   <5   <5
:Little Fork River
Little Fork         22.0   24.0   26.0 :  <5   <5   <5   <5   <5   <5
:Vermilion River
Crane Lake          14.0   16.0   18.0 :   7   12   <5   <5   <5   <5

Legend
CS = Conditional Simulation (Current Outlook)
HS = Historical Simulation
FT = Feet

In Table 2 below...the 95 through 5 percent columns indicate the
probability of exceeding the listed stage levels (FT) for the valid
time period.

...Table 2--Exceedance Probabilities...

                               Chance of Exceeding Stages
                                  at Specific Locations
                          Valid Period: 02/17/2025 - 05/18/2025
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite              3.6    4.0    4.5    5.5    6.9    8.0    8.5
:Mississippi River
Aitkin                7.0    7.5    8.6   10.6   12.0   14.1   14.8
Fort Ripley           6.2    6.3    6.9    8.0    9.6   10.8   11.8
:St. Croix River
Danbury               2.1    2.3    2.7    3.5    4.3    5.8    6.6
:Snake River
Pine City             5.3    5.5    6.0    6.4    7.4    8.4    9.1
:St. Louis River
Scanlon               5.6    5.8    6.6    7.4    8.3    9.9   10.4
:Knife River
Near Two Harbors     27.8   27.9   28.3   28.8   29.3   29.7   30.9
:Nemadji River
South of Superior    10.6   11.5   13.3   15.6   18.6   22.4   22.9
:Tyler Forks
Mellen                6.1    6.2    7.2    7.8    8.9   10.4   11.9
:Bad River
Near Odanah           5.7    5.8    6.8    7.4    9.2   12.4   13.5
At Odanah             3.7    3.8    4.4    5.1    6.0    7.3    8.4
:South Kawishiwi River
Ely                   4.3    4.5    4.9    5.4    6.0    6.4    6.7
:Little Fork River
Little Fork           5.5    5.9    6.8    8.1   10.6   12.6   16.8
:Vermilion River
Crane Lake            8.4    8.8   10.0   10.8   11.8   13.4   14.7

In Table 3 below...the 95 through 5 percent columns indicate the
probability of falling below the listed stage levels (FT) for the
valid time period.

...Table 3--Nonexceedance Probabilities...

                            Chance of Falling Below Stages
                                 at Specific Locations
                          Valid Period: 02/17/2025 - 05/18/2025
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite              0.1    0.1    0.1    0.1    0.1    0.1    0.1
:Mississippi River
Aitkin                1.1    1.1    1.1    1.1    0.9    0.6    0.5
Fort Ripley           1.9    1.9    1.9    1.9    1.7    1.4    1.3
:St. Croix River
Danbury               0.8    0.8    0.7    0.7    0.7    0.7    0.7
:Snake River
Pine City             0.1    0.1    0.1    0.1    0.1    0.1    0.1
:St. Louis River
Scanlon               0.8    0.8    0.8    0.8    0.8    0.8    0.8
:Knife River
Near Two Harbors      0.0    0.0    0.0    0.0    0.0    0.0    0.0
:Nemadji River
South of Superior     0.0    0.0    0.0    0.0    0.0    0.0    0.0
:Tyler Forks
Mellen                0.0    0.0    0.0    0.0    0.0    0.0    0.0
:Bad River
Near Odanah           0.1    0.1    0.1    0.1    0.1    0.1    0.1
At Odanah             0.2    0.2    0.2    0.2    0.2    0.2    0.2
:South Kawishiwi River
Ely                   0.1    0.1    0.1    0.1    0.1    0.1    0.1
:Little Fork River
Little Fork           0.2    0.2    0.1    0.1    0.1    0.1    0.1
:Vermilion River
Crane Lake            0.1    0.1    0.1    0.1    0.1    0.1    0.1

These long-range probabilistic outlooks contain forecast values that
are calculated using multiple season scenarios from 30 or more years
of climatological data...including current conditions of the
river...soil moisture...snow cover...and 30 to 90 day long-range
outlooks of temperature and precipitation. By providing a range of
probabilities...the level of risk associated with long-range planning
decisions can be determined. These probabilistic forecasts are part
of the National Weather Service`s advanced hydrologic prediction
service.

Visit our web site weather.gov/dlh for more weather and water
information.

Visit the North Central River Forecast Center for the Greater
Mississippi Spring Flood Outlook briefing.
https://storymaps.arcgis.com/stories/746318e235604583934a78c639e19946

For additional information on stream flow conditions for USGS
locations please reference https://dashboard.waterdata.usgs.gov
For additional information on stream flow conditions at MNDNR sites
www.dnr.state.mn.us/waters/csg/index.html
or
www.climate.umn.edu/dow/weekly_stream_flow/stream_flow_weekly.asp
For more information on climate outlooks reference
www.cpc.ncep.noaa.gov

The next outlook will be issued February 27th.

$$