Flood Potential Outlook
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
001
FGUS73 KABR 132005
ESFABR
MNC011-155-SDC013-017-021-025-029-031-037-039-041-045-049-051-057-
059-065-069-075-085-089-091-107-109-115-117-119-129-212015-
Probabilistic Hydrologic Outlook
National Weather Service Aberdeen SD
305 PM CDT Thu Mar 13 2025
...SPRING FLOOD AND WATER RESOURCE OUTLOOK...
This Spring Flood Outlook is for the rivers and streams in northeast
South Dakota, portions of central South Dakota, and portions of west
central Minnesota.
With a current lack of existing snow cover, dry antecedent soils,
and diminishing river ice, the chances for minor, moderate, or major
flooding across much of the region are generally below normal. The
flood threat through this spring, both in location and severity,
will largely be determined by future rain or snowfall.
The 6 to 10 day outlook through March 23rd is for increased chances
for above normal temperatures and equal chances for below, near or
above normal precipitation. The outlook for the remainder of the
month of March is for above normal temperatures and below normal
precipitation. The 90 day outlook for March through May is for equal
chances for below, near or above normal temperatures and
precipitation.
A significant early spring storm system will bring widespread
precipitation to eastern parts of the region March 14 and 15th. At
this time, this precipitation is not expected to result in river
flooding or result in any significant change to the overall spring
river flood outlook. Some within-bank rises, especially on smaller
creeks and stream, are expected as is ponding of water where
subsurface frost remains.
...CURRENT SNOW CONDITIONS...
There is currently no snow cover across the entire area.
...CURRENT SOIL CONDITIONS...
Soil moisture is below normal across the entire area. While many
locations are still reporting frost, some thawing of the top layer
has occurred and the remaining frost is likely now `primed` for
removal. The entire region is in Moderate to Severe drought
conditions.
...CURRENT RIVER CONDITIONS...
River ice has largely been eroded or is rotting in place, with a
diminishing risk of any ice jam related flooding going forward.
River levels and flows are generally running near to below normal.
...Probabalistic Outlooks...
In Table 1 below, the current (CS) and historical (HS) or normal
probabilities of exceeding minor...moderate...and major flood stage
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 greater 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:
Valid Period: 03/17/2025 - 06/15/2025
: 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
-------- ----- ----- ----- : --- --- --- --- --- ---
:Elm River
Westport 14.0 16.0 19.0 : <5 28 <5 22 <5 9
:James River
Columbia 13.0 16.0 18.0 : 15 58 11 42 6 29
Stratford 14.0 17.0 18.5 : 21 58 9 41 5 31
Ashton 13.0 14.0 16.0 : 11 58 9 47 6 42
Redfield 20.0 22.0 25.0 : 9 45 8 44 6 42
:Snake Creek
Ashton 11.5 13.0 16.0 : 12 53 11 53 6 43
:Turtle Creek
:Big Sioux River
Watertown 10NW 10.0 11.0 12.0 : <5 19 <5 <5 <5 <5
Watertown Conifer 9.0 10.0 12.0 : <5 63 <5 35 <5 <5
Watertown Broadwy 10.5 11.0 13.5 : <5 35 <5 34 <5 <5
Castlewood 9.0 11.0 16.0 : 6 35 <5 28 <5 <5
:Grand River
Little Eagle 15.0 17.0 21.0 : <5 27 <5 19 <5 7
:Moreau River
White Horse 21.0 23.0 25.0 : <5 22 <5 17 <5 11
:Bad River
Fort Pierre 21.0 25.0 27.0 : 6 12 <5 5 <5 <5
:Little Minnesota
Peever 17.0 22.0 24.0 : 7 27 <5 <5 <5 <5
:Minnesota River
Big Stone Lake 970.0 971.5 973.5 : <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:
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Elm River
Westport 4.5 4.5 4.5 5.1 7.1 9.5 10.9
:James River
Columbia 6.3 6.3 6.3 7.2 12.5 17.0 18.5
Stratford 7.7 7.7 7.7 9.3 12.8 16.9 18.7
Ashton 4.5 4.5 4.5 5.8 8.2 13.4 22.8
Redfield 4.5 4.5 4.6 5.7 8.5 18.6 28.4
:Snake Creek
Ashton 1.7 1.7 1.7 2.3 5.8 14.8 18.7
:Turtle Creek
:Big Sioux River
Watertown 10NW 4.5 4.5 4.8 6.2 7.0 8.2 8.7
Watertown Conifer 5.8 5.8 5.8 6.8 7.5 8.2 8.8
Watertown Broadwy 5.2 5.2 5.3 6.1 7.0 8.3 9.3
Castlewood 5.1 5.1 5.3 6.0 6.9 8.2 9.4
:Grand River
Little Eagle 3.6 3.7 5.1 6.6 9.1 10.0 12.0
:Moreau River
White Horse 2.4 5.0 7.2 10.4 13.4 16.7 19.7
:Bad River
Fort Pierre 0.5 1.7 3.6 5.7 11.2 18.8 22.4
:Little Minnesota
Peever 11.1 11.3 11.7 12.8 14.4 16.4 18.0
:Minnesota River
Big Stone Lake 966.4 966.4 966.5 966.5 966.5 966.9 967.8
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:
LOCATION 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Elm River
Westport 4.5 4.5 4.4 4.4 4.4 4.4 4.4
:James River
Columbia 5.6 5.6 5.4 5.1 4.9 4.9 4.9
Stratford 7.5 7.4 7.0 6.7 6.4 6.4 6.4
Ashton 4.2 4.2 4.2 4.0 3.6 3.5 3.5
Redfield 4.2 4.2 4.2 4.1 3.5 3.4 3.4
:Snake Creek
Ashton 1.7 1.7 1.7 1.7 1.7 1.7 1.7
:Turtle Creek
:Big Sioux River
Watertown 10NW 4.2 4.1 4.1 4.1 4.1 4.1 4.1
Watertown Conifer 5.2 5.1 5.1 5.0 5.0 5.0 5.0
Watertown Broadwy 5.0 5.0 4.9 4.9 4.9 4.9 4.8
Castlewood 4.7 4.6 4.5 4.5 4.4 4.4 4.4
:Grand River
Little Eagle 3.5 3.5 3.4 3.4 3.4 3.3 3.3
:Moreau River
White Horse 2.2 2.2 2.2 2.1 2.1 2.0 1.9
:Bad River
Fort Pierre 0.5 0.5 0.5 0.5 0.5 0.5 0.5
:Little Minnesota
Peever 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Minnesota River
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 by the end of March.
$$
Parkin