Flood Potential Outlook
Issued by NWS Aberdeen, SD

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000
FGUS73 KABR 192138
ESFABR
MNC011-155-SDC013-017-021-025-029-031-037-039-041-045-049-051-057-
059-065-069-075-085-089-091-107-109-115-117-119-129-042100-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
338 PM CST THU FEB 19 2015

...SPRING FLOOD OUTLOOK...

THIS SPRING FLOOD OUTLOOK IS FOR THE RIVERS AND STREAMS IN NORTH
CENTRAL AND NORTHEASTERN SOUTH DAKOTA AND EXTREME WEST CENTRAL
MINNESOTA.

GENERALLY SPEAKING...THE CHANCES FOR MINOR FLOODING THIS SPRING ARE
NEAR NORMAL TO SLIGHTLY BELOW NORMAL...WITH MAINLY BELOW NORMAL
CHANCES FOR MODERATE OR MAJOR FLOODING. ICE JAM FLOODING REMAINS A
THREAT ACROSS THE REGION THROUGHOUT THE LATE WINTER AND EARLY SPRING.

...CURRENT SNOW CONDITIONS...

THE NORTHERN PORTIONS OF THE REGION HAVE A TRACE TO LESS THAN 3
INCHES OF SNOW ON THE GROUND...WITH A WATER EQUIVALENT OF ONE INCH
OR LESS. THE WESTERN AND SOUTHERN AREAS ARE GENERALLY SNOW FREE.

...CURRENT SOIL CONDITIONS...

FROST DEPTHS IN THE SOILS GENERALLY ARE RUNNING BETWEEN 5 AND 15
INCHES. THIS IS MAINLY DUE TO THE RECENT COLD TEMPERATURES IN THE
LAST TWO WEEKS WITH LITTLE SNOW COVER TO INSULATE THE GROUND. THE
WARM WEATHER IN LATE JANUARY TO EARLY FEBRUARY HAD ALLOWED MANY
AREAS TO LOSE MOST OF THE FROZEN SOILS BEFORE THIS RECENT COLD SNAP.
SOIL MOISTURE IS GENERALLY NORMAL TO SLIGHTLY BELOW NORMAL FOR MOST
AREAS DUE TO DRY CONDITIONS LATE IN THE FALL AND THE LACK OF A
SIGNIFICANT SNOW COVER OR SNOW MELT THIS WINTER. THE NATIONAL
DROUGHT MONITOR HAS CLASSIFIED ALL BUT THE FAR WESTERN PORTION OF THE
REGION AS BEING D0...OR ABNORMALLY DRY...WITH THE FAR NORTHEASTERN
PART OF THE REGION BEING CLASSIFIED AS D1...OR MODERATE DROUGHT.

...CURRENT RIVER CONDITIONS...

MOST RIVERS AND STREAMS IN THE AREA ARE ICE COVERED AND HAVE LEVELS
THAT ARE SLIGHTLY BELOW NORMAL.

...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:  2/21/2015 - 5/22/2015

                                       :    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 :  27   15   19    8    9    5
:JAMES RIVER
COLUMBIA            13.0   16.0   18.0 :  63   42   43   26   32   18
STRATFORD           14.0   17.0   18.5 :  73   48   52   30   23   20
ASHTON              13.0   14.0   16.0 :  60   31   54   30   43   24
:TURTLE CREEK
REDFIELD             7.0   10.0   15.0 :  32   37   17   14    5    8
:JAMES RIVER
REDFIELD            20.0   22.0   25.0 :  33   18   31   15   22   14
:BIG SIOUX RIVER
WATERTOWN           11.5   12.5   13.5 :  10   27   <5   12   <5   <5
WATERTOWN            9.5   11.5   13.5 :  56   53   23   26   <5    5
WATERTOWN - BROAD   11.0   14.0   16.0 :  42   45   <5   <5   <5   <5
CASTLEWOOD           9.0   11.0   16.0 :  49   50   25   29   <5   <5
:GRAND RIVER
LITTLE EAGLE        15.0   17.0   21.0 :  24    8    7    6   <5   <5
:MOREAU RIVER
WHITEHORSE          21.0   23.0   25.0 :   8    8    7    7    5    5
:BAD RIVER
FORT PIERRE         21.0   25.0   27.0 :  14   18    8   <5    7   <5
:LITTLE MINNESOTA RIVER
PEEVER              17.0   22.0   24.0 :   7   23   <5   <5   <5   <5
:MINNESOTA RIVER
BIG STONE LAKE     971.5  973.0  975.0 :  <5   <5   <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: 2/21/2015 - 5/22/2015
LOCATION              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:ELM RIVER
WESTPORT              6.5    6.9    8.1   12.0   14.4   18.8   20.1
:JAMES RIVER
COLUMBIA              8.1    8.5    9.8   15.0   19.1   20.3   20.6
STRATFORD            11.0   11.5   13.7   17.1   18.3   20.1   20.4
ASHTON                6.8    7.2   10.0   15.1   19.1   24.0   27.0
:TURTLE CREEK
REDFIELD              3.3    3.3    4.0    5.6    7.5   11.2   14.8
:JAMES RIVER
REDFIELD              6.3    6.5    8.8   13.3   23.2   27.7   30.7
:BIG SIOUX RIVER
WATERTOWN             5.8    6.0    6.8    7.8    9.0   10.0   10.8
WATERTOWN             5.6    6.0    6.9    8.6   10.0   10.3   11.0
WATERTOWN - BROAD     6.4    6.7    7.7    9.9   11.6   12.7   13.3
CASTLEWOOD            5.4    5.6    7.4    8.7   11.0   12.0   13.2
:GRAND RIVER
LITTLE EAGLE          5.1    5.8    8.5   11.4   15.0   16.1   18.2
:MOREAU RIVER
WHITEHORSE            3.8    4.6    7.1   10.8   16.0   20.1   24.9
:BAD RIVER
FORT PIERRE           5.3    6.0    7.9   11.3   17.3   24.2   29.8
:LITTLE MINNESOTA RIVER
PEEVER               11.1   11.4   11.8   12.8   13.9   16.5   17.6

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: 2/21/2015 - 5/22/2015
LOCATION              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:ELM RIVER
WESTPORT              3.0    3.0    3.0    3.0    3.0    3.0    3.0
:JAMES RIVER
COLUMBIA              5.0    5.0    5.0    5.0    5.0    5.0    5.0
STRATFORD             5.4    5.4    5.4    5.4    5.3    5.3    5.3
ASHTON                3.6    3.6    3.6    3.6    3.6    3.5    3.5
:TURTLE CREEK
REDFIELD              3.1    3.1    3.1    3.1    3.0    3.0    3.0
:JAMES RIVER
REDFIELD              3.3    3.3    3.3    3.2    3.1    3.0    2.9
:BIG SIOUX RIVER
WATERTOWN             3.8    3.8    3.8    3.8    3.8    3.8    3.8
WATERTOWN             4.1    4.1    4.1    4.1    4.1    2.0    2.0
WATERTOWN - BROAD     5.5    5.5    5.5    5.5    5.5    5.5    5.5
CASTLEWOOD            4.5    4.5    4.5    4.5    4.5    4.4    4.4
:GRAND RIVER
LITTLE EAGLE          3.2    3.2    3.2    3.2    3.2    3.2    3.2
:MOREAU RIVER
WHITEHORSE            3.1    3.1    3.1    2.9    2.8    2.7    2.6
:BAD RIVER
FORT PIERRE           2.6    2.6    2.6    2.6    2.6    2.6    2.6
:LITTLE MINNESOTA RIVER
PEEVER               10.1   10.1    9.7    9.7    9.7    9.7    9.7

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 ON THURSDAY MARCH 5TH.

$$

PARKIN












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