Flood Potential Outlook
Issued by NWS Aberdeen, SD

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FGUS73 KABR 031939
ESFABR
MNC011-155-SDC013-017-021-025-029-031-037-039-041-045-049-051-057-
059-065-069-075-085-089-091-107-109-115-117-119-129-221200-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
1257 PM CST THU MAR 03 2016


...Spring Flood Outlook...

This Spring Flood Outlook is for the rivers and streams in central
and northeastern South Dakota and west central Minnesota.

Very little snow cover remains across the area. The spring flood
threat will be mainly determined by future rains or snowfall. The
outlook for the next 2 weeks indicates the best chances are for
normal precipitation.  The 30 day outlook for the entire month of
March shows chances for normal to slightly above normal
precipitation. The 90 day outlook for March through May shows equal
chances for above normal, normal, or below normal precipitation.

For the Upper James, Big Sioux,and Little Minnesota river basins, the
chances for minor, moderate, or major flooding are below normal. For
the river basins across the north central or middle Dakota area,
chance for minor, moderate or major flooding are also below normal.

...Current Snow Conditions...

Little to no snow cover remains except for an area from just north of
Pierre, south along the Missouri River.  However, even in this area,
snow cover is less than 2 inches and water equivalent of the snow is
less than one half inch.

...Current Soil Conditions...

Frost depths across the area remain at or slightly below normal.
Frost depths range from 15 to 24 inches north of Highway 212 and 5 to
15 inches south of the highway.

...Current River Conditions...

River and streams are at or near normal across the vast majority of
the area.  Most rivers north of highway 14 have a fair amount of ice
remaing to melt or be flushed downstream.

... Probabilistic Outlooks...

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:  03/05/2016  - 06/03/2016

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Elm River
Westport            14.0   16.0   19.0 :  <5   12   <5   10   <5    8
:James River
Columbia            13.0   16.0   18.0 :  13   37    9   27   <5   18
Stratford           14.0   17.0   18.5 :  22   46   12   28   <5   15
Ashton              13.0   14.0   16.0 :  16   31   15   29    7   24
:Turtle Creek
Redfield             7.0   10.0   15.0 :  32   44   17   20   <5    9
:James River
Redfield            20.0   22.0   25.0 :  12   21   11   17    8   16
:Big Sioux River
Watertown           10.0   11.0   12.0 :   6   28   <5   11   <5   <5
Watertown            8.0   10.0   12.0 :  27   54   <5   28   <5   <5
Watertown - Broad   11.0   14.0   16.0 :  27   45   <5   <5   <5   <5
Castlewood           9.0   11.0   16.0 :  36   51   16   28   <5   <5
:Grand River
Little Eagle        15.0   17.0   21.0 :  21    7   14    6   <5   <5
:Moreau River
Whitehorse          21.0   23.0   25.0 :  30    7   22    6   12   <5
:Bad River
Fort Pierre         21.0   25.0   27.0 :  13   18   <5   <5   <5   <5
:Little Minnesota River
Peever              17.0   22.0   24.0 :  <5   24   <5   <5   <5   <5
:Minnesota River
Big Stone Lake     971.5  973.0  975.0 :  <5    6   <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: 03/05/2016  - 06/03/2016
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Elm River
Westport              5.1    5.1    5.1    5.5    6.7   10.2   12.9
:James River
Columbia              7.1    7.1    7.1    7.3   10.2   14.6   17.5
Stratford             9.2    9.2    9.2    9.3   12.7   17.2   17.9
Ashton                5.1    5.1    5.1    5.2    8.3   15.1   19.7
:Turtle Creek
Redfield              4.1    4.1    4.1    5.3    8.4   11.5   12.8
:James River
Redfield              5.8    5.8    5.8    6.9   12.0   23.6   24.5
:Big Sioux River
Watertown             5.2    5.3    6.1    7.3    8.2    9.8   10.1
Watertown             4.3    4.6    5.1    5.9    8.8    9.6    9.7
Watertown - Broad     6.2    6.7    7.4    8.9   11.3   12.2   12.4
Castlewood            5.4    5.6    6.5    7.8   10.6   11.4   11.6
:Grand River
Little Eagle          5.1    5.1    5.3   11.1   14.9   17.7   18.1
:Moreau River
Whitehorse           12.6   12.6   12.6   13.7   22.1   25.2   25.9
:Bad River
Fort Pierre           7.1    7.1    7.4    9.0   16.5   22.7   24.1
:Little Minnesota River
Peever               10.5   10.6   11.0   12.1   13.2   15.2   16.7
:Minnesota River
Big Stone Lake      967.7  967.8  967.9  968.0  968.0  968.2  968.6

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: 03/05/2016  - 06/03/2016
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Elm River
Westport              4.9    4.8    4.7    4.6    4.5    4.5    4.5
:James River
Columbia              6.5    6.4    5.9    5.4    5.2    5.2    5.2
Stratford             8.7    8.6    8.0    7.3    7.2    7.1    7.0
Ashton                4.9    4.8    4.3    3.7    3.3    3.1    3.1
:Turtle Creek
Redfield              3.7    3.5    3.4    3.3    3.2    3.2    3.2
:James River
Redfield              5.4    5.2    4.6    3.9    3.5    3.4    3.3
:Big Sioux River
Watertown             4.2    4.1    4.1    4.0    3.9    3.9    3.9
Watertown             3.8    3.7    3.7    3.7    3.7    2.9    2.9
Watertown - Broad     5.7    5.7    5.6    5.6    5.5    5.5    5.5
Castlewood            4.7    4.7    4.6    4.6    4.5    4.4    4.4
:Grand River
Little Eagle          3.2    3.1    3.1    3.1    3.0    3.0    3.0
:Moreau River
Whitehorse            3.0    2.9    2.9    2.8    2.7    2.7    2.7
:Bad River
Fort Pierre           2.8    2.7    2.7    2.7    2.7    2.7    2.7
:Little Minnesota River
Peever               10.0    9.6    9.6    9.6    9.6    9.6    9.6
:Minnesota River
Big Stone Lake      967.5  967.5  967.5  967.5  967.5  967.5  967.5

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/abr for more weather and water
information.

The next outlook will be issued late next month.

$$







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