Flood Potential Outlook
Issued by NWS Duluth, MN

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000
FGUS73 KDLH 030057
ESFDLH
MNC001-017-021-031-035-061-071-075-115-137-WIC003-007-013-031-
051-099-113-129-092300-

Probabilistic Hydrologic Outlook
National Weather Service Duluth MN
634 PM CST Thu Mar 02 2017

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:  03/05/2017 - 06/03/2017

                                       :    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 :  87   49   60   31   18    8
Fort Ripley         10.0   12.5   26.0 :  86   51   27   22   <5   <5
:Snake River
Pine City            9.0   10.0   11.0 :  <5    8   <5   <5   <5   <5
:St. Louis River
Scanlon             10.5   11.0   13.0 :   9    7   <5    6   <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: 03/05/2017 - 06/03/2017
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite              6.6    6.9    7.7    8.2    8.7    9.3   10.0
:Mississippi River
Aitkin               11.4   12.6   14.2   15.5   17.0   18.9   19.5
Fort Ripley           9.2    9.8   10.5   11.3   12.6   13.7   14.1
:Snake River
Pine City             5.2    5.2    5.6    6.2    7.2    8.1    8.6
:St. Louis River
Scanlon               6.8    7.3    7.9    8.7    9.2   10.5   10.9

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: 03/05/2017 - 06/03/2017
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite              4.2    4.1    4.1    3.9    3.7    3.7    3.5
:Mississippi River
Aitkin                8.1    8.0    7.5    6.7    5.3    4.5    4.2
Fort Ripley           6.8    6.7    6.4    5.9    5.4    5.0    4.7
:Snake River
Pine City             3.6    3.5    3.4    3.3    3.2    3.1    3.1
:St. Louis River
Scanlon               4.3    4.2    4.2    3.9    3.7    3.5    3.4

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.

The snowpack varies from south to north across the Northland with
the highest values occurring across the Minnesota Arrowhead. Much of
Northeastern Minnesota along and north of US Highway 2 has water
content in the 4-6 inch range. Lower amounts of a trace to 1 inch are
seen in much of western Koochiching County and south of US 2. Higher
amounts to 6-8 inches are seen east of a Two Harbors-Ely line with a
small pocket of 8-10 inches being seen north of Grand Marais.
Northwestern Wisconsin is predominately in the trace to 1 inch range
with isolated pockets of 1 to 2 inches near Grantsburg, just south of
Hurley and southeast of Prentice. Much of the snowpack melted during
a string of well above normal days in late February. A strong winter
storm missed much of the region to the south at the end of the string
of warm days, but did bring some snow to parts of northwestern
Wisconsin.

Actual snow cover has diminished considerably over the past few
weeks. Snow cover across northeastern Minnesota is generally in the 8
to 12 inch range. This diminishes to 4 to 8 inches south of a Bena-
Remer-McGregor-Moose Lake line. South of a Brainerd to Sandstone
line, snow cover drops to about 2 inches or less. Areas south of a
Walker to Longville line in Cass County have a trace to 2 inches on
the ground. Some pockets of a trace to 2 inches are also seen across
western Koochiching County. The greatest snow cover is seen across
Lake and Cook Counties where 16 to 20 inches are seen east of a Two
Harbors to Babbitt line. Embedded higher amounts to 20 to 30 inches
are located north of Silver Bay and north of Grand Marais. Snow cover
is more scarce across northwestern Wisconsin. Areas of 2 to 6 inches
are observed from Douglas county into Bayfield, Ashland, Iron and
Price Counties, although southeastern Douglas, southwestern Bayfield
and areas near and just south of Ashland fall to a trace to 2 inches.
Higher amounts to 8 to 12 inches are seen south of Wisconsin Highway
77 in Iron County and in southeastern Price County. The remainder of
northwestern Wisconsin has 2 inches or less of snow cover. However, a
small pocket of 4-10 inches is holding on just southwest of
Grantsburg. For more information on snow pack and water equivalent,
visit http://www.nohrsc.noaa.gov.

Precipitation since the beginning of December has been above normal
across most of the area. In Wisconsin, Burnett County and the
northern reaches of Ashland and Iron Counties are running slightly
below normal for the period. The region received a boost in
precipitation in the latter half of February when temperatures went
above normal and a storm system moved through with moderate to heavy
rainfall in addition to thunderstorms. This helped all areas trend
near to above normal, but a drier spell over the last week has seen
short term deficits across the St. Croix Valley, the Minnesota
Arrowhead and areas north of the Iron Range. For the December through
February period, northeastern Minnesota is seeing the highest
departures from average, with precipitation running some 2-4 inches
above normal across northeastern St. Louis, Lake and Cook Counties.
An active pattern is expected across the region over the next two
weeks leading to near to above normal precipitation. The overall
flooding threat remains relatively low and is dependent more on heavy
rainfall events than snowmelt.

Temperatures in the March 8th to March 12th period look to run above
normal across northwestern Wisconsin and areas south of Minnesota
Highway 210 with the remainder of northeastern Minnesota seeing near
normal temperatures. All areas look to trend near normal for the 8 to
14 day period running March 10th through 16th. Precipitation will run
above normal through both the 6 to 10 and 8-14 day periods.

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

For additional information on stream flow conditions for USGS
locations please reference
for Minnesota   www.waterdata.usgs.gov/mn/nwis/rt
for Wisconsin   www.waterdata.usgs.gov/wi/nwis/rt

for additional information on stream flow conditions at
MN DNR locations...reference
www.dnr.state.mn.us/waters/csg/index.html
or
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 by the end of March.

$$

GSF/BJH








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